REPORT NO. EPA 907/9-77-001
EVALUATION OF THE STANDARD SAMPLING TECHNIQUE
FOR
SUSPENDED SOLIDS
BY
U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION VII
SURVEILLANCE & ANALYSIS DIVISION
TECHNICAL SUPPORT BRANCH
FIELD INVESTIGATIONS SECTION
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Evaluation of The Standard Sampling
Technique for Suspended Solids
by
U. S. Environmental Protection Agency, Region VII
Surveillance and Analysis Division
Technical Support Branch
Field Investigations Section
Gregory D. Reed, Ph. D.
1977
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1
Disclaimer
Mention of brand name of equipment does not constitute endorsement
or recommendation of a product by the Environmental Protection
Agency, but is used for illustrative purposes only.
SUPERINTENDENT OF DOCUMENTS
CLASSIFICATION NUMBER IS:
EP 1.2: Ev 1/2
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11
Acknowledgement
The Environmental Protection Agency, Region VII Field Investigation
Section wishes to acknowledge the cooperation of the Johnson County
Kansas Sewer District in allowing the section to conduct the sus-
pended solids study at one of their wastewater treatment facilities.
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iii
Table of Contents
Page No.
Disclaimer i
Acknowledgement ii
Table of Contents iii
List of Figures iv
Abstract vi
I. Introduction 1
II. Review of Previous Work 3
A. Solids in Wastewater 4
B. Settling Characteristics 6
C. Sampler Evaluation 7
D. Standard Sampling Procedure 9
III. Procedure 10
A. Selection of the Resin 14
B. Tagging the Resin 16
C. Copper Analysis 16
D. Equivalency Determination 17
E. Non-filterable Solids Analysis 17
IV. Results 18
V. Discussion 36
VI. Conclusions 46
VII. Future Work 47
VIII. References 49
Attachment #1
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IV
List of Figures
ure No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Sketch of the sampling
Sampler recovery of 0.2
resin at an intake velo
Sampler recovery of 0.2
resin at an intake velo
Sampler recovery of 0.2
resin at an intake velo
Relative recovery of re
intake velocity of 0.9
Relative recovery of re
intake velocity of 2.5
Relative recovery of re
intake velocity of 0.9
Non-filterable solids s
intake velocity of 0.9
Non-filterable solids s
intake velocity of 2.5
Non-filterable solids s
intake velocity of 0.9
Relative variation of t
solids as a function of
Sampler recovery of 0.0
resin at an intake velo
Relative recovery of re
Sampler recovery of 0.8
resin at an intake velo
Relative recovery of re
Effect of particle size
recovery at the 0.2 dep
test facility
97 to 0.149 mm
city of 0.9 fps.
97 to 0.149 mm
city of 2.5 fps.
97 to 0.149 mm
city of 0.9 fps.
sin #2 at an
fps.
sin #2 at an
fps.
sin #2 at an
fps.
ampled at an
fps.
ampled at an
fps.
ampled at an
fps.
he non-filterable
sample time.
74 to 0.044 mm
city of 2.5 fps.
sin #1.
40 to 0.297 mm
city of 2.5 fps.
sin #3.
on particle
th.
Page No.
11
19
20
22
23
24
25
26
27
28
30
31
32
34
35
39
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Figure No. Page No.
17 Effect of particle size on particle 40
recovery at the 0.6 depth.
18 Effect of particle size on particle 41
recovery at the bottom of the channel.
19 Effect of particle size on particle recovery 42
at mid-depth in the hydraulic jump.
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VI
Abstract
The inconsistency of non-filterable solids data resulting from
automatic sampling equipment used by the Surveillance and Analysis
Division, Region VII, United States Environmental Protection Agency,
was evaluated from a field sampling technique viewpoint. Resins
and other solids of varying specific gravity and particle size were
tagged with a metal salt or fluorescent material and added to a
waste stream as a synthetic suspended solid to determine the collec-
tion efficiency of the samplers. Recovery of the metal salt or
fluorescence was used as the indicator of solids recovery. A 832,000
liters per day (220,000 gallon per day) raw domestic wastewater
flow was used to conduct the test. Recovery of solids in the hydrau-
lic jump below the Parshall flume, and at the 0.6 depth in the approach
channel above the flume was 25 percent below the theoretical homogeneous
concentration indicated by the resin feed rate. The results indicate
the need for a method of evaluating the wastewater characteristics
for proper sample intake tube placement.
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1
I. INTRODUCTION
The increases in population and technology create a larger and
larger demand upon our water resources. The use of these waters
produces various wastewaters that are released back into the
hydrologic cycle. In order to protect the quality of water resources
for aquatic life and reuse by others, the wastewaters generated must
be cleansed of harmful impurities prior to their discharge. One
of the problems in monitoring these inputs and discharges of waste-
water treatment systems is the accurate quantification of any given
constituent in the liquid stream. A sample that is representative
of the total flow, not only for that moment, but also for the longer
period of time is essential for the determination of the suitability
of a wastewater for release into a natural receiving water. Fluc-
tuations in the chemical and physical constituent concentrations
found in wastewaters have a dramatic impact on the acceptability
of the quality of that wastewater.
Several interrelated parameters are normally selected to monitor
the performance of wastewater treatment works. One of these is
the non-filterable solids (suspended solids) content. The nonfil-
terable solids (NFS) parameter was selected for this test program
because previous work (2) has shown it to be the most difficult
constituent to collect for representative samples. Since no primary
analytical standard currently exists for the NFS test (1), NFS data
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2
are subject to view with a skeptical eye. However, secondary
treatment is defined by NFS and is a prime regulatory parameter
on discharge permits and in municipal pretreatment ordinances for
industrial users of the sewer system. Therefore, it is important
to evaluate the valididty of the NFS data prior to making a deci-
sion of acceptability of an influent waste, discharge, or treatment
system. Historically, the inference has been that when a liquid
sample is withdrawn, by any process, all of the constituents are
present in the same concentrations as existed in the original flow
stream. Harris and Keffer (2) have indicated that the resulting
NFS data for a raw municipal wastewater stream monitored concur-
rently with more than one commercial automatic sampler can vary
by as much as 300 percent, depending on the type of automatic
sampler used.
Parameter variation of this magnitude demands development of a
method for evaluating the solids sampling capability of the numer-
ous automatic samplers available. This study was directed toward
determining if the standard sampling procedures used by the Surveil-
lance and Analysis Division would in fact provide a truly accurate
sample of the wastewater under study.
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3
II. REVIEW OF PREVIOUS WORK
As the need for monitoring wastewaters grew, automatic sample col-
lection became an economically attractive alternative to traditional
manual methods. Data resulting from these automatic samplers have
become an important element of the environmental decision making
process. The impact of these decisions clearly indicate the need
for wastewater samples which are truly representative of the source.
The characteristics of most wastewaters are constantly changing
because of cyclical and diurnal variation. Additionally, there
are temporary surges of the constituent concentrations. Interim't-
tant grab samples do not average out these variations; consequently
composite samples are used to blend together the highs and lows
to form a more representative sample. Compositing, which requires
numerous samples over a long period of time (i.e., 24 hours), requires
too much manpower to be economically accomplished manually. Auto-
matic compositors have been introduced to release the operator
requirement and to improve the accuracy of the collected samples.
There are many different types and forms of automatic samplers on
the market. Shelley and Kirkpatrick (3) and Harris and Keffer (2)
have provided detailed assessments of the most common samplers in
use by describing the good and bad features of each piece of equip-
ment. The difficulty in obtaining representative and reliable
suspended solids data from automatic samplers has been demonstrated
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4
by Harris and Keffer (2). Shelly and Kirkpatrick (3) have attemp-
ted to outline the characteristics of common sampling equipment
so that monitoring of a given wastewater can be achieved with the
proper equipment. However, even this type of assessment has not
solved the solids sampling problems. An appraisal of the indivi-
dual wastewater solids characteristics as well as the automatic
sampler characteristics may be required to effectively select the
monitoring equipment. An understanding of the types and range
of solids that potentially can be found in wastewater will provide
a clearer insight of the magnitude and complexity of the solids
monitoring problem.
A. Solids in Wastewater
Domestic and industrial wastewaters contain highly variable amounts
of dissolved, colloidal, and suspended solids. Because of the large
number of sources, wastewater solids are found in a variety of sizes
and densities. Approximately 75 percent of municipal suspended
solids are organic and approximately half of the organic solids
are settleable (4,5). Non-filterable solids are generally considered
to be anything larger than 0.45 micron with settleable solids assumed
to be larger than 10 microns. The specific gravity of these solids
ranges from less than unity for floatable solids to a maximum around
2.65 for grit and higher for certain industrial wastes. Approximately
30 to 40 percent of the organic content of raw municipal wastewater
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5
is contained in solids that will tend to settle when put in a
quiescent condition. These solids may become part of the bed-
load in a wastewater pipe or channel.
The separation and distribution of solids that occurs in gravity
flow systems is controlled mainly by the settling velocity of each
particle. The settling velocity is, in turn, a function of the
particle size, shape, density or specific gravity, and drag coeffi-
cient with a possible settling enhancement from natural flocculation
(6). Because of the large variation of particle characteristics
found in domestic wastewaters, the separation and distribution
cannot necessarily be predicted for any one parameter. A large
organic particle with a specific gravity just slightly greater than
one could have the same settling velocity as a small sand particle
with a specific gravity of 2.65. If the settling effects of a
particle were the only controlling parameters, all of the suspended
solid particles in a wastewater would settle out of the main flow
stream given a long enough channel. However, there is a flow velo-
city that, when exceeded, will entrain or scour the settling material
(7,8). For a given flow situation, some of the suspended solids
will remain in suspension and another portion will eventually set-
tle to the bottom. Therefore, the most representative sample location
will be at a different position for different wastewaters.
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6
Position of the sample intake tube becomes just as important as
intake configuration and sample transport mechanism. In most waste-
waters, there is a nonuniform distribution of solids from the top
to the bottom of the channel.
B. Settling Characteristics
Suspended solids in a stream flowing under perfectly laminar con-
ditions would be expected to settle to the bottom of the channel
at a rate determined by their settling velocity. Eventually all
of the suspended solids would drop to the bottom. This principle
is used in settling systems, such as water and wastewater sedimenta-
tion tanks, to provide for solids removal. However the conditions
involved in the transport of wastewater from one place to another
are very seldom laminar in nature.
Turbulent flow presents a different condition in terms of the solids
distribution. Intuitively, we would expect the lighter, smaller
solids to be more uniformly mixed than the heavier, larger solids.
In general, the solids that have settling velocities, in the Stoke's
law range (NR <.l) would be distributed more or less uniformly.
An inspection of the settling velocity relationship for the Stoke1s
law region (NR <.l)
-------
Vs - £d_ (s.g. -1)
18 v
where: Vs= settling velocity of the particle, L/t
2
g = acceleration of gravity, L/t
d = particle diameter, L
2
v = kinematic viscosity, L /t
s.g.= specific gravity of the particle
and the Reynold's number equation; NR = Vd_ = £ d| (s.g. -1) reveals
e v 18 v
that at constant temperature, many combinations of particle size
and specific gravity will produce a condition that would result
in a uniform distribution of solids. Therefore, uniform distribution
is not necessarily restricted to low specific gravity materials.
The conditions of the transition zone (O.!
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8
the wastewater from the flow stream to a sample container. The
characteristics of these mechanisms that affect the solids sampling
capability are of the most importance for this study. Most of the
samplers use a pump, either peristaltic (the most popular), piston,
impeller, or vacuum. Some use a direct withdrawal into a container
under a vacuum. Whichever method is used, the velocity in the intake
tube should be controllable and the mechanism should be able to
pass the solids that are picked up in the intake tube.
The intake velocity is an important parameter that must be controlled.
Studies (3) have indicated that the velocity should be equal to
the free stream velocity with a minimum criteria of 0.79 to 1.18
meters per second (m/sec) [2 to 3 feet per second (fps)]. The mini-
mum velocity provides for protection against settling of particulates
in the intake tube during collection. Discussions by Shelley and
Kirkpatrick (3) have emphasized the importance of isokinectic
conditions for particulate sampling.
A major problem in wastewater sampling is blockage of the intake
tube by solids in the wastewater. Small diameter tubes aggravate
this problem, so tubes with inside diameters of at least 1 centi-
meter (cm) [0.38 inch (in.)] are recommended. The larger sizes
reduce plugging but do not entirely eliminate the problem; con-
sequently, automatic purging of the intake lines at regular
intervals in the sampling cycle is very important to continual
operation.
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9
The primary question pertaining to sampling methodology that has
not been answered is where to place the intakes to obtain a sample
that is representative of the total flow stream. This study was
concerned primarily with the recovery of solids with a specific
gravity greater than one and does not address the problem of
floating solids.
D. Standard Sampling Procedure
The standard sampling procedure used by the Surveillance and Anal-
ysis Division of Region VII on raw wastewater is as follows. A
plastic or aluminum intake tube is positioned in the wastewater
flow such that it is opening directly into the flow. The location
of first choice is the mid-depth of a hydraulic jump. In the
absence of a jump, the tube is placed in the throat of a Parshall
flume or at mid-depth in the approach channel. The tube is con-
nected to an automatic sampler equipped with a suction device
«
capable of withdrawing the sample at a transport velocity equal
to or greater than the stream flow velocity but always greater than
1 fps (0.3 mps). For most of the better currently available com-
mercial wastewater sampling equipment, the intake line is purged
with air prior to the withdrawal of each sample. The samples are
withdrawn at specified time intervals into individual containers.
It is the validity of the NFS samples collected by this method
that is being investigated in this study.
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10
III. Procedure
The purpose of this study was to determine if the standard sampling
procedures would, in fact, accurately recover an artificial waste-
water solid that was present in a wastewater flow at a known
concentration. The investigative site was a small, package, acti-
vated sludge treatment plant, located on the south side of Kansas
City. A sketch of the test facility is shown in Figure 1. The
plant was equipped with a 7.6 cm (3.0 in.) Parshall flume with 2
meters (m) [5 feet (ft)] of rectangular approach channel. The nor-
mal flow rate of wastewater was approximately 831,600 liters per
day (I/day) [220,000 gallons per day (gpd)] and provided 15.2 cm
(6 in.) of depth in the approach channel. The facility received
domestic waste only and was located within 1.6 kilometers (km) [1.0
mile] of the residential area that it served. According to past
records, the NFS varied from 96 to 190 mg/1 and the flow has reached
as high as 1.55 x 10 I/day (410,000 gpd) after a rain.
A sewer line junction box was located 20 m (50 ft) upstream from
the flume. The box was 2.4 m (6.0 ft) by 2.4 m (6.0 ft) by 1.6
m (4.0 ft) deep and provided a convenient location to add the syn-
thetic solid. The synthetic wastewater suspended solid was applied
at a known rate with a BIF Omega Model 22-01 low rate feeder which
was positioned to deposit the solid directly into the wastewater
flow as shown in Figure 1. The channel changed direction in both
BIF, 345 Harris Avenue, Providence, Rhode Island 02901
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,0
,.
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12
the horizontal and vertical directions simultaneously at this posi-
tion. The dual change in flow direction caused the wastewater to
produce a spiral type of rolling action that created a high degree
of mixing.
The BIF feeder was chosen because of its consistent and reproducible
feed rates. The machine was simply a cylindrical storage hopper
over a horizontal, grooved disk. The rotation of the eccentric
disk, which was controlled by a variable speed transmission, caused
any given point in the groove to be alternately exposed to the inte-
rior of the hopper, for filling of the groove, and to the exterior
of the hopper for emptying of the groove by a scaper blade. The
solid material was pushed off the edge of the disk by the blade
and fell through a hole in the underside of the apparatus. The
feed rate was controlled by the size of the groove and the rotational
speed of the disk.
A chelating resin tagged with copper was used as the artificial
wastewater solid. The concentration of applied solids in the waste-
water could be determined by the amount of copper found to be present
in excess of the background concentrations. The brand name of the
resin was Chelex 100 which was a styrene lattice with an iminodi-
acetic acid exchange group. This resin had an equivalence of 0.104
mg of copper per mg of resin. The particles were spherical and had
*
Bis-Rod Laboratories, 32nd and Griffin, Richmond, California 94804
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13
a specific wetted gravity of 1.15. Several different size particles
were used to provide different suspension and settling characteristics,
In addition to the resin, a number 17 silica grade of Ottawa quartz
sand* (specific gravity of 2.65) coated with an arc yellow Day-Glo
fluorescent dye and sealed with plastic was fed to obtain bed load
recovery data. The intent was to use the readings from a fluorometer
as the indicator of the concentration of solids recovered during
the sampling process. This attempt was not successful because of
apparent interferences in the wastewater system or in the measure-
ment technique. The data reported is from the resin applications
only.
Four sampling points were examined, three one-foot upstream from
the flume in the center of the approach channel at the 0.2 and 0.6
depth, on the bottom of the channel, and one downstream in the
center of the existing hydraulic jump. The tube opening in the
jump was located 15 to 30 cm (6 to 12 in.) downstream from the
leading edge of the stationary wave. In addition, background cop-
per samples were collected in the sewer upstream from the resin
feeder by an automatic sampler. All of the intake tubes were 1.0
cm (0.38 in.) inside diameter (ID) Tygon tubing positioned to open
directly into the flow stream (similar to a pitot tube arrangement).
*
Ottawa Silica Company, Ottawa, Illinois
**
Switzer Brothers, Inc., Cleveland, Ohio
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14
The samples were withdrawn directly from the channel into one-liter
cubitainers by a variable speed sampler built in the Region VII
laboratory. (See Attachment #1). The individual depth samples
were not taken simultaneously. The samples were collected one at
a time in the order given above with approximately 15 seconds
required for each sample. The sampler utilized a variable speed
peristalic pump controlled by purge and sample timers that could
be adjusted to various cycles. The sampler was set so that the
intake tube was completely purged with air prior to the collection
of a sample. The sampler was located less than 0.5 m (18 in.)
directly above the wastewater surface during sampling. The samples
were mechanically collected in the same manner as they would be
by an automatic sampler; namely, a purge of the line and on immedi-
ate collection of approximately 800 ml of the wastewater. The flow
rate was measured by positioning a Sigmamotor Bubbler depth sensor
in the channel and using the Parshall flume dependency on depth
as the indicator of flow. The bulk velocity in the channel was
*
measured by positioning an Ott meter at approximately mid-depth.
A. Selection of the Resin
A weak acid cation exchange resin, Chelex 100 (a styrene divinyl-
benzene copolymer containing imi nodi acetate functional groups),
was chosen as the synthetic suspended solid because of its high
affinity for copper, an element easily measured at small concentra-
*
Weathermeasure Corp., 3213 Orange Grove Ave.,
North Highlands, California 95660
Model F581 Water Current Meter
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15
tions. This resin was used to take advantage of controllability
of size, shape, and density. An additional advantage was the resis-
tance of this material to elution of copper while suspended in raw
domestic wastewater. Therefore the amount of copper found during
analysis is a known function of the solids added based on the
equivalence of the resin.
The equivalency of copper on the resin (mg of copper per mg of
resin) is needed to convert the copper concentration in mg/1 to
solids concentration in mg/1. Since copper can be readily measured
at concentrations below one mg/1, the amount of resin added to the
wastewater could be kept relatively small while still obtaining
reliable results. The volume of material required would prohibit
a direct solids addition. Restrictions imposed by the feeding
apparatus required the resin to be dry. Drying the resin interfered
with mixing because of water surface tension. This problem was
solved by applying a liquid detergent onto the resin before drying.
This detergent effectively broke the surface tension and permitted
complete suspension of the resin. The equivalency of the resin
was determined after the drying had been performed by stripping
the copper with nitric acid. The equivalency of the resins used
varied from 0.102 to 0.108.
Both the copper and NFS tests were run on the samples. The samples
were delivered unpreserved to the EPA Region VII lab to prevent
*
25 Funston Road, Kansas City, Kansas 66115
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16
loss of suspended solids. In order to improve precision in the
copper analysis, the entire sample was acidified after the NFS test.
B. Tagging The Resin
Approximately 225 grams (g) [0.5 lb.] of wet resin (around 75 per-
cent moisture) was placed in a large ion exchange column. The
column and resin was rinsed with deionized water. A four-fold
excess of copper (16 percent copper sulfate solution) was eluted
through the column. The excess copper was rinsed from the column
with deionized water until no copper was detectable in the elutant.
The resin was then transferred to a Buchner funnel and the excess
water removed by vacuum. The funnel was then filled with 7X brand
laboratory detergent, allowed to soak for a few minutes, and the
excess was removed by vacuum. The resin was then dried at 50° C
in a vacuum oven.
C. Copper Analysis
A 100 ml portion of the acidified, well mixed sample was added to
a 250 ml Erlenmeyer flask. Five ml of concentrated nitric acid
was added and the sample boiled down to about 50 ml. The sample
was cooled and filtered through a Whatman number one paper filter
to remove any solids. The filtrate was brought back to the original
volume with deionized water. The copper measurement was performed
*
Linfro Scientific, Inc., Division of Flow Laboratories,
Hamden, Connecticut 06514
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17
on an Instrumentation Laboratories Model 453 atomic absorption
spectrophotometer.
D. Equivalency Determination
A 50-mg portion of the copper tagged resin was placed in a one-liter
volumetric flask with a small amount of deionized water. The copper
was dissolved from the resin with 10 ml of concentrated nitric acid.
The resulting solution was diluted to one liter. The final solution
was then analyzed for copper on the atomic absorption spectrophotometer.
E. Non-filterable Solids Analysis
A 25-ml portion (measured with a large tip pipette) of the blended,
well mixed sample was filtered through a previously tared small
Gooch crucible containing a glass fiber filter. The Gooch was dried
at 105° C overnight. The crucibles were then cooled and reweighed.
*
Jonspin Road, Wilmington, Massachusetts 01887
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18
IV. Results
A field sampling program was performed to measure the solids col-
lection effectiveness of the most common automatic sampler mechanism
utilized by the EPA Region VII Surveillance and Analysis Division;
namely a peristaltic pump with 0.95 cm (0.38 in.) tubing positioned
to open directly into the wastewater flow. Three different sized
resins of the same wetted specific gravity (1.15) were fed into
the wastewater flow to serve as the indicator of the effectiveness
of solids collection in normal sampling procedures. The different
settling characteristics of these resins was based on particle size;
(1) 200 to 325 mesh [0.074 to 0.044 mm (0.0029 to-0.0017 in.)] in
Stoke's law valid zone, (2) 50 to 100 mesh [0.297 to 0.149 mm (0.0117
to 0.00587 in.)] in the transition zone, and (3) 20 to 50 mesh [0.840
to 0.297 mm (0.0331 to 0.0117 in.)] in the Stoke's law invalid zone.
Resin number 2 was sampled under two intake conditions; (1) isoki-
neticly, at a free stream velocity of 0.27 m/sec (0.9 fps), and
(2) at the recommended minimum of 0.76 m/sec (2.5 fps). The first
condition is shown in Figure 2. The line connects the mean values
at each depth sampled. The jump values (taken at mid-depth in the
hydraulic jump downstream from the Parshall flume) are shown on
the left as a reference of the relationship between that sampling
position and the others. A homogeneous distribution would result
in a resin ratio for all three depths of 1.0. The second condition
is shown in Figure 3. There was no appreciable difference between
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1.4-
1.2-
MEAN
[CUMULATIVE SYSTEM ERROR
i.o-
8-
6-
4-
Figure 2: Sampler recovery of 0.297 to 0.149 mm
resin at an intake velocity of 0.9 fps.
'JUMP 'BOTTOM
'.8
'.6
'.4
DEPTH
'.2
TOP
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20
1.4-
1.2-
MEAN
_ CUMULATIVE SYSTEM ERROR
1 0-
.8-
.4-
.2-
Figure 3: Sampler recovery of 0.297 fo 0.149 mm
resin at an intake velocity of 2.5 fps .
'JUMP 'BOTTOM
'.2
TOP
DEPTH
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21
these two results except at the 0.6 depth, which may have been due
to tube placement. Since there was no difference, and to help
insure that all the solids were transported properly, all of the
remaining samples were collected at an intake velocity of 0.76 m/sec
(2.5 fps). Notice that the sample collected in the jump did not
achieve full recovery of the resin, as is sometimes assumed.
The first condition was repeated on a different sampling day and
the results are shown in Figure 4. The results were the same as
the previous samples which were under different flow and solids
conditions (it had rained two days prior to the first set of data).
The variation in the resin data was larger than expected but gen-
erally within the cumulative error of the equipment used to obtain
the number (i.e., resin feeder ±2 percent, flow chart recorder ±2
flume ±4 percent, and copper analysis ±2 percent). The relative
changes in recovery at each sample position with progressing sample
collections are shown in Figures 5, 6, and 7 for the same conditions
shown in Figures 2, 3, and 4, respectively. Although it is not
shown as strongly in Figures 5 and 6, the curves in Figure 7 seem
to indicate the recovery of resin was directly influenced by the
flow rate. This possibility will be examined further for its
implications on the results later.
The NFS was also measured for each condition and are shown in Figures
8, 9, and 10. The mean values are shown for comparison of the NFS
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22
1.4-
1.2-
MEAN
.CUMULATIVE SYSTEM ERROR
1.0-
n -8-
o
t—
<
z
.6-
.4-
.2-
Figure 4: Sampler recovery of 0.297 to 0.149 mm
resin at an intake velocity of 0.9 fps .
'JUMP 'BOTTOM
'.6
'.4
TOP
DEPTH
-------
c
a
01
TO
—
O
<'
a
it
to
o
^
Q
O
* O
I =
"n <— 00 O O
F 3 3 » "
"o o o o
3 o
•o -o
ro
CO
FLOW, gpd (xio-3)
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24
1/1
LU
0 0.2 Depth
*—— 0.6 Depth
H——«• Bottom
A^—— Jump
•••••Flow
4001
350i
300"
O)
11 12 13 14 15 16 17 18
Figure 6: Relative recovery of resin #1 at an intake velocity of 2.5 fps.
-------
Oil"" 0.2 Depth
Jfc— — 0.6 Depth
B—— Bottom
A—•-"— Jump
25
Z .84
1 2 3 4 5 6 7 8 9 10 11 12 13 14
SAMPLE SET NUMBER
2 SOW
200i
150J
Figure 7: Relative recovery of resin #2 at an intake velocity of 0.9 fps.
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26
700-
600-
500-
O 400-
300-
200-
100-
MEAN
FIGURE 8: Non-filterable solids sampled at an intake velocity of 0.9 fps.
TOP
-------
700-
27
600-
MEAN
500-
O 400.
300-
200-
100-
FIGURE 9: Non-filterable solids sampled at an intake velocity of 2.5 fps.
'JUMP 'BOTTOM '.8 '.6 '.4
DEPTH
TOP
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28
300-
O 200-
100 -
MEAN
FIGURE 10: Non-filterable solids sampled at an intake velocity of 0.9 fps.
"JUMP BOTTOM
'.6 '.4
DEPTH
'.2
'TOP
-------
29
distribution to the resin distribution. The variation in the NFS
data is primarily due to the change in wastewater characteristics
with time of the day as is illustrated by Figure 11. The wide
variation in the bottom sample results illustrates the difficulty
in obtaining a representative sample. The distribution of NFS
followed approximately the same pattern as resin number 2.
Resin number 1 was small enough to be governed by the conditions
under Stoke's law. Therefore, a nearly uniform distribution of
resin was anticipated. The results of the sampling test are shown
in Figure 12. The variation of this data was the most severe of
any of the sampling test. It was observed during sampling that
this resin was not entirely distributed as discrete particles.
The particles had a tendency to coalesce, possibly from influences
of surface charges induced in the tagging and drying procedure or
a reocurrence of a hindrance to dispersion by surface tension forces
or a surface wetting problem.
An examination of the variations in concentration with each progres-
sive sample shown in Figure 13 reveals that the unusually high
or low values were accompanied by off-setting values at another
sample position. The resin was totally recovered when looking at
all three depth measurements together, even though an individual
value may have been high or low.
-------
250
200
O)
E
150
i -y/v
\i j/ / /
100
8 9 10 11 12 13
SAMPLE SET NUMBER
15 16 17 18
FIGURE 11: Relative variation of the non-filterable solids as a function of sample time.
-------
RESIN RATIO :
concentration sampled
concentration added
4k
I
o>
I
00
I
C
5
-o
a>
O
O
O
c
TO
a a
-. 3
3 1L
0 a
o
-0
2 b
10 o
-2
ii
n
c
3
m
>
z
50
O
.. .1
-------
32
Omni 0.2 Depth
*—— 0.6 Depth
B—— Bottom
A1—^™ Jump
I
1.4i
1.3i
1.2i
l.H
l.Oi
O
i= .91
<
Of.
Z .81
in
LU
at
.7"
.61
.Si
•.4i
#
'6
300i
250i
i
o
£
O
200"
4 5 6 7 8 9 10 11
SAMPLE SET NUMBER
FIGURE 13: Relative recovery of resin #1
-------
33
Resin number 3 was the largest tested and had characteristics that
put it in the category where Stoke's law was invalid. This resin
was expected to exhibit a very marked difference in concentration
from top to bottom. The resin recovery is shown in Figure 14.
The resin concentrations for the bottom samples were much lower
than had been expected. The other values were generally in the
range anticipated. The recovery as a function of sample time shown
in Figure 15 illustrates the apparent sampling problem for the
bottom sample position and the consistency of the other positions.
-------
34
1.4-
1.2-
MEAN
.CUMULATIVE SYSTEM ERROR
1.0-
.8-
o
t—
<
z
.6-
.4-
.2-
FIGURE 14: Sampler recovery of 0.840 to 0.297 mm
resin at an intake velocity of 2.5 fps .
DEPTH
TOP
-------
35
0.2 Depth
0.6 Depth
Bottom
Jump
300m*
250i
-o
a
w
200*
1 2 3 4 5 6 7 8 9 10 11 12 13 14
SAMPLE SET NUMBER
FIGURE 15: Relative recovery of resin #3
-------
36
V. Discussion
There are primarily two areas of interest in this study, (1) the
determination of the recovery effectiveness of the standard sampling
procedure and mechanism used by the SVAN Division, and (2) the
determination of what the NFS data derived from a sampling survey
means in terms of the actual homogeneous concentration of the
wastewater flow.
A comparison of Figures 2, 3, and 4 with Figures 8, 9, and 10 reveals
that resin number 2 exhibited the same general concentration dis-
tribution in the wastewater flow as did the non-filterable solids.
The concentration found in the mid-depth of the hydraulic jump was
the same as the concentration found at approximately the 0.6 depth
in the channel upstream of the flume. Also, the resin recovery
in the hydraulic jump was consistently 74 percent (±6) of what would
have been the homogeneous concentration of resin if complete mixing
had been accomplished. Using this number, the average hydraulic
jump NFS concentration of 127 mg/1 would then indicate an actual
NFS value for the total wastewater flow of 172 mg/1. Therefore,
sampling this particular wastewater flow in the hydraulic jump by
the standard procedure would produce a number that is 26 percent
too low. In addition, sampling this flow at approximately 0.6 depth
(0.5 to 0.65) would also produce a value that was approximately
26 percent below what is actually present in a homogeneous mixture
of the entire flow. Another way of looking at this sampling infor-
-------
37
mation would be to state that the sample tube would have to be placed
at 0.8 to 0.9 depth in order to recover a concentration that is
equivalent to the actual NFS concentration of the wastewater. How-
ever, it must be remembered that the change in concentration with
depth is very rapid and highly variable at these depths and the
positioning of the intake tube would have a very critical effect
on the validity of the sample. Another complicating factor is the
variation in solids concentration at the lower depths because of
inconsistent scouring activity. It would be more reliable to sample
at a depth where the change in ctepth had very little effect on the
concentration and then adjust the result to produce the true con-
centration number. In other words, the wastewater solids distribu-
tion would have to be calibrated prior to or during sampling.
Resin number 1, being smaller than resin number 2 and in the region
where Stoke's law is valid, should have and did produce a more nearly
uniform distribution than resin number 2. Resin number 3, represent-
ing the Stoke's law invalid region, was chosen to produce a less
uniform distribution than number 2, which it did except for the
bottom sample. This may have been caused by deposition of the resin
in the sewer pipe, which prevented it from reaching the sample station
during the sampling period.
The relationships between the distributions of these three resins
can be illustrated by plotting the functional dependence of the
-------
38
resin recovery on the particle size for each sample position as
shown in Figures 16, 17, 18, and 19^ The 0.2 and 0.6 depth sample
positions, Figures 16 and 17 respectively, produced lower and lower
recoveries for larger and larger particle sizes, as would be expec-
ted. The apparent misalignment of the data for the largest particle
distribution in Figure 16 can be explained by the fact that smallest
particles would tend to be the only ones recovered near the surface
and consequently, skew the effective size distribution to the left.
The bottom samples (Figure 18) did not recover the resin properly.
As the particle size increases, the concentration should increase
proportionately. The results shown in Figures 16 and 17 indicate
a progressive envelope that defines the relationship between recov-
ery at that depth and the particle size. This was not true for
resin number 3 at all and the result of resin number 2 may be slightly
lower than it actually existed. The envelope described by the first
two particle sizes indicated that the largest size distribution
should have produced a recovery ratio around 1.5 instead of the
0.45 achieved. The information on Figure 18 supports the conclu-
sion drawn previously that something prevented the proper recovery
of the largest resin. There are two possibilities for this discre-
pency. The sample tube may not have been able to pick large particles
up off the bottom of the channel. This possibility does not seem
likely since the intake velocity was much higher than the settling
velocity of the particles. The other possibility is a leveling
-------
1.3.
39
o
TJ
C
O
0)
c
o
+1
1.2.
1.1-
i.o-
.9-
••-
.7-
HORIZONTAL LINE - particle size
distribution
VERTICAL LINE - + one standard
deviation
'-envelope of probable
occurrence
to
Ul
ex.
.4H
.3-
.2-
.4 .5 .6 .7 ' .8
PARTICLE SIZE, mm
r
.9
1.0
1.1
1.2
FIGURE 16: Effect of particle size on particle recovery at the 0.2 depth.
-------
40
1.3-
1.2-
1.1-
c 1.0-
o
5. .9-
-o
-a
-0
c
o
.8-
.7-
± .6^
g
i-
< .5H
4_
m ••» n
oc
.3-
HORIZONTAL LINE - particle size
distribution
VERTICAL LINE - + one standard
deviation
envelope of probable
occurrence
*
*
*
*
*
•
*
*
*
*
*
•
*
*
*
*
*
*
\
%%
\
X
x
X
*
*
1 1 1 1 I 1 II II II
.1 .2 .3 .4 .5 .6 .7 .8 .9 1.0 1.1 1.2
PARTICLE SIZE, mm
FIGURE 17: Effect of particle size on particle recovery at the 0.6 depth.
-------
41
>
a
-o
-s
c
D
at
c
o
+1
<
at
1.3-
1.2.
1.1-
1.0-
.9-
.7-
.6-
.5-
«/> Am
iu ••»n
Q£
.3-
HORIZONTAL LINE - particle size
distribution
VERTICAL LINE - + one standard
deviation
envelope of probable
occurrence
i i I I i I ii
.1 .2 .3 .4 .5 .6 .7 .8
PARTICLE SIZE, mm
I
.9
T i
1.0 1.1
1.2
FIGURE 18: Effect of particle size on particle recovery at trie bottom of
the channel.
-------
42
o
-a
o
-a
c
o
at
c
o
1.3-
1.2.
1.1-
1.0-
.9-
.8-
.7-
±! -6-
Of
Z
.3-
.2-
—I— HORIZONTAL LINE - particle size
' distribution
VERTICAL LINE - + one standard
deviation
-envelope of probable
occurrence
.1 .2 .3 .4 .5 .6 .7 .8
PARTICLE SIZE, mm
l I I I
.9 1.0 1.1 1.2
FIGURE 19: Effect of particle size on particle recovery at mid-depth
in the hydraulic jump.
-------
43
of the slope or a "dead" spot in the pipe before it discharged into
the entrance structure of the treatment plant. This hydraulic dis-
continuity would have provided for settling of the resin which may
not have had time to work its way down to the sample location during
the relatively short sampling period (one-half to three quarters
of an hour after the resin feed was started). This condition would
also explain why the resin recovery appeared to be directly related
to the flow rate. An increase in flow would have tended to flush
the system better and decrease in flow would have permitted more
settling in the pipe.
The underlying assumption behind all of this data is that the resfh
actually arrived at the test location. A rough check of the total
mass found for resin number 1 and number 2 would indicate that the
correct amount of resin did reach the test location. The results
for resin number 3 indicate a deficit at the bottom of the channel
and possibly a deficit at the 0.6 depth. The possible causes of
this deficit have been discussed previously. The resin that appeared
at the test section behaved in a predictable manner even if it was
sometimes erratic. The same general relationship between the data
collected from jump area and the upstream channel held in all cases,
however. f
The effect of particle size on particle recovery for the sampling
station in the hydraulic jump is shown in Figure 19. The data again
-------
44
defines a progressive envelope to define the functional relation-
ship between size and recovery. A comparison of Figures 17 and
19 reveals that the envelopes of occurrence for the 0.6 depth and
the mid-depth in the hydraulic jump were, for all practical purposes,
the same. Therefore, either position could be samples and get com-
parable results. However, it sould be observed that sampling in
the hydraulic jump will not necessarily produce a concentration num-
ber that is the homogeneous value. The larger, denser particles,
occurring predominately on the bottom of the channel, will tend
to ride under the turbulence of the jump and not necessarily become
remixed into the flow.
An examination of the results of the NFS analyses reaffirms previ-
ous statements about its variability with respect to both position
and time in a wastewater flow. It is this inherent variability
that has produced the questions about the validity of the solids
data. This set of conditions must be recognized and lived with.
The premise of this study was the need to "calibrate" the waste-
water collection characteristics in order to determine the true
homogeneous NFS concentration from the samples taken. The results
of this study indicate that the NFS distribution conditions can
be calibrated by the use of a synthetic wastewater solid that has
similar characteristics. The application of this method provides
a technique to prove the representativeness of the samples taken
from a wastewater stream; which is somethin of concern to surveil-
lance and enforcement personnel.
-------
45
Even though this study presented additional information about the
effectiveness of the standard sampling method and apparatus for
monitoring untreated domestic wastewater, it did not provide veri-
fication that the same relationships would be true for other equip-
ment or wastewaters. Further study will be required to determine
the relative effectiveness between various types of equipment on
various types of wastewater.
-------
46
VI. Conclusions
The information gathered by this study resulted in the following
conclusions:
1. A wastewater sampling procedure and mechanism can be "calibrated"
for a given wastewater flow by the use of a resin or some similar
material.
2. The results for NFS obtained for raw wastewater by the standard
sampling procedures used by the EPA Region VII Surveillance and
Analysis Division for a wastewater similar to the one used in this
study are lower than the actual homogeneous concentrations. In
this case, the NFS values obtained at the standard sampling positions
were 26 percent lower.
3. Single sampling points should not be located in areas of steep
concentrations gradients to minimize the error due to tube location.
4. A method is needed to classify compatible types of sampling
equipment and wastewater flows.
-------
47
VII. Future Work
The need for accurate and reliable non-filterable solids data cre-
ates the demand for some method of determining how to sample a given
wastewater without expending a lot of time and money. This study
has demonstrated the feasibility of using an artificial wastewater
solid to determine the accuracy of a sampling procedure. The next
step would be to develop a method to quickly and easily match a
wastewater to a standard artificial wastewater solid that has been
previously "calibrated". This procedure would allow for the deter-
mination of the optimum sample collection scheme for the determination
of the correction factor to be applied to the data to produce the
actual homogeneous NFS concentration value. Additionally, this
type of procedure could be used to classify the reliability or
accuracy of the different types of automatic samplers when used
to sample various types of wastewaters.
The Environmental Protection Agency currently is considering pro-
posals (re. RFP No. CI-76-0260) to include investigations that would
provide the answers for the sampler equipment and intake problems
along with the preliminary information necessary to begin to deter-
mine the feasibiltiy of calibrating a given wastewater to a previously
calibrated synthetic wastewater solid, as outlined in the previous
paragraph.
-------
48
The calibration investigation would require the determination of
the matching characteristic of the natural and artificial solids.
One possibility is that the settling characteristics are sufficient
for indexing sampling equipment and methods with wastewater types.
Potentially, a settling flux or some similar settling parameter
could be used to describe both the natural and synthetic solids
to a particular sampling procedure. If this was accomplished, a
set of calibrated curves could be developed using the data gathered
with synthetic solids relating the flux characteristics of the waste-
water solids to the sampling effectiveness in the form of best location
of intake, type of equipment, or proper correction factor to be
applied to the laboratory data.
A preliminary study to determine whether this type of approach is
feasible could be accomplished by a principal investigator, techni-
cian, and two lab chemists in a three month period. If the preliminary
study proved successful, another three to six months of data collection
on various wastewaters could prove its versatility.
-------
49
VIII. References
1. Standard Methods for The Examination of Water and Wastewater.
13th Edition, American Public Health Association, New York, New York,
1971.
2. Harris, D.J, and Keffer, W.J., Wastewater Sampling Methodologies
and Flow Measurement Techniques, Region VII Surveillance and Analysis
Division, U.S. Environmental Protection Agency, Kansas City, Missouri,
1974.
3. Shelley, P.E. and Kirkpatrick, G.A., An Assessment of Automatic
Sewer Flow Sarnplers. Office of Research and Monitoring, U.S.
EnVi ronmenta1 Prot ection Agency, Washington, D.C., 1973.
4. Fair, 6.M., Geyer, J.C., and Okun, D.A., Elements of Water
Supply and Wastewater Disposal. John Wiley and Sons, New York, 1971.
5. Hunter, J.V. and Heukelekian, H., "The Composition of Domestic
Sewage Fractions", Journal of the Water Pollution Control Federation,
volume 37, August 1965.
6. Eckenfelder, W.W., Industrial Water Pollution Control, McGraw-
Hill Book Company, New York, 1966.
7. Gilluby, J., Waters, A.C., and Woodford, A.O., Principles of
Geology, W.H. Freeman and Company, San Francisco, 1968.
8. Camp, T.R., "Grit Chamber Design", Sewage Works Journal,
volume 14, January-December, 1942.
9. Rickert, D.A. and Hunter, J.V., "General Nature of Soluble and
Particulate Organics in Sewage and Secondary Effluent", Water
Research, Pergamon Press, London, 1971.
-------
VARIABLE SPEED
WASTEWATER SAMPLER
r
-------
PURPOSE
This variable speed sampler was developed for use in a study
of the pick-up of solids from a wastewater flow. The idea was to
have the intake velocity of the sampler as nearly equal to the ve-
locity of the flow as possible. This sampler is also capable of
reproducing the intake velocities of many of the commercial waste-
water compositors in use.
THEORY OF OPERATION
This sampler was designed around a peristaltic pump driven by
a gear-reduced reversible DC motor with a variable speed controller.
A Potter & Brumfield KRP 14DG 115VDC relay is used in place of the
FORWARD-REVERSE switch on the speed controller. It also switches
the motor to full speed when running in the reverse direction (purge
cycle). SEE DIAGRAM.
When the manual sample switch is thrown or the switch closes in
the HG105A6 timer, power is applied to the motor controller through
the CG60A6 timer, the relay through the CG10A6 timer, and the timing
device in the CG10A6, This starts the purge cycle which will last
for however long the CG10A6 is set for. After that period of time,
the switch in the CG10A6 will throw applying power to the timing de-
vice in the CG60A6 and allowing the relay to return to the sample
cycly position, A sample will be drawn at the speed set on the speed
-------
2
controller for the length of time set on the CG60A6. The switch in
the CG60A6 will then throw and disconnect the power from the motor
controller.
The CG10A6 and CG60A6 timers will reset themselves when power
is removed by either moving the manual switch to "off" or the switch
in the HG105A6 timer returns to "off."
FUTURE ADDITION OF POST-PURGE
A post-purge cycle may be added, if desired, by simply connecting
Pin #3 of the CG60A6 to Pin #4 of the CG10A6. After the sample is
drawn, it will purge until the manual switch is thrown off or the
switch in the HG105A6 returns to "off."
A timed post-purge may be added with the use of another CG10A6.
Pin #3 of the CG60A6 should be connected to Pins #1 and #2 of the new
CG10A6. Pin #7 of the new CG10A6 should go to common (Pin #7 of the
CG60A6, etc.) and Pin #4 of the new CG10A6 should go to Pin #4 of the
first CG10A6. It will then post-purge for however long the new CG10A6
is set for.
-------
WIRING DIAGRAM
Common
120 VAC
1
Manual
Ground
Hot
SPOT Center Off
Auto
/I
CG10A6 /
2
5 /
HG105A6
\dx
—'"off*
\c
Purge
20 MFD
/ °v
3^' Sample
KRP 14DG
51
11
O^!-
* This particular timer is wired
backwards from most
\
V
'
CG60A6
30 '
Motor Controller
=j
•f
O
Motor
-------
PUMPING VELOCITIES
VELOCITIES IN FEET PER SECOND
Motor Speed
Setting
100
95
90
85
80
75
70
65
60
55
50
45
40
35
30
25
20
15
1/4" Intake Tube
30" Head
4.75
4.64
4.62
4,46
4.40
4,13
4.02
3.96
3.77
3.54
3.33
3.07
2.76
2.44
2.09
1.66
1.21
.72
24" Head
4.79
4.66
4.47
4.41
4.30
4.21
4.00
3.97
3.85
3.56
3.27
3.07
2.73
2.44
2,05
1.66
1.24
.78
3/8" Intake Tube
24" Head
2.30
2.26
2.19
2.09
1.96
1.90
1.80
1.73
1.61
1.52
1.37
1.26
1.11
.97
.79
.63
.48
.29
Pumping heads were measured from the center of the pump
Velocities were measured after the water reached the pump
Motor speed settings below 15 are not practical
-------
BULLETIN 158
TIME DELAY RELAY
CG CG5OO SERIES-ON DELAY
CGS30A6 . . . Tim* D«fay ReJay
Surfat* Mounting
CGSOO SerUt . . . F«el Meuntlng
Versatile .. . Compatible . .. Solid State
The "CG" series lime delay relay, available in either the octal
base plug-in case or ihe surface mounting case is a versatile,
highly compatible time delay relay
Octal Base Plug-In Case
Available with 8 pin or 1} pin plug.
Plugs into standard 8 or 11 pin socket.
Case of high'impact resistant cycofac
Models available for remote operation.
Models available with fixed timing period.
Surface Mounting Relay Case
Case of flame proof, high Impact resistant Noryl.
Case material recognized by UL as sole support device for
current carrying components.
Pilot light standard.
Models available for remote operation.
Models available with fixed timing period.
SPECIFICATIONS
Selection Chart
Electrical Ratings
Coil 120 volts 50'60 cycle 2.5 watts.
Also available for 240V. 50/60 cycle; 12,
24, 110 volts D.C. on special orders.
Contact Rating
10 Amps, 120 V.A.C.
CG-DPDT
CG500-3PDT
Reset Time
50 milliseconds minimum off time is
quired to reset the timer.
Dial Setability
Dial Readt directly in seconds.
Time Delay will be within 13% of full
scale.
Repeat Accuracy
£ 2% at 102 to 132 voltage variation.
4- 10% at temperature increase to I40*F.
Mounting
See page 2.
Mechanical Life Expectancy
24 million operations.
I million operations® 10 amp.
l20VACresistiv«
SYMBOL NUMBERS
Plu3-in
CG2A6
CG10A6
CC30A6
CG60A6
Surfoc*
Mt9 C»i
CG502A6
CG510A6
CG530A6
CG560A6
DIAL SPECIFICATIONS
Dial
R«n0e
2 Sec.
10 See
30 Sec.
60 Sec
M.mmum
050 See
.060 Sec.
.150 See.
300 Sue,
Dial
2 Sac.
ISee
5 See.
5 Sec.
BULLETIN 158
TIME DELAY RELAY
CG SERIES
WIRING DIAGRAMS
Standard On Delay Operation
Apply power to pins 2 and 7 to start timing. After de-
lay contacts 1-4 and 8-5 open, 1-3 and 8-6 close. Re-
moving power resets contacts to original position
shown.
Apply power to pins 2 and 7 to start timing. After
delay contacts 1-4, 8-5, and A-D open, 1-3, 8-6, and
fl-C close. Removing power resets contacts to original
position shown.
TIME ADJUSTMENTS
The standard "CG" timer is furnished with a knob
mounted on top which is used to adjust the time delay.
By ordering this unit with the suffix *"02" or *"04"
(see chart) it is furnished without the knob and wired
as shown so that an external potentiometer can be
used. The potentiometer should be connected with
either a shielded lead or twisted pair of wires.
Eagle Signal has available a "remote pot kit" which
includes the knob, dial, and 2 watt potentiometer to
bo used when remote setting Is desired.
TYPE
Oclol
Plug-,.,
CG2A602
CG10A602
CG30A602
CG60A6D2
Surface
Mtg Ca»
CG502A604
CG510A604
CG530A404
CG560A604
Dial
Range
2 Sec.
ID Sec.
30 Set.
60 Sec.
REMOTE POTENTIOMETER
SPECIFICATION
PatentieiMler
Bat 11 tone*
1 Meg. Ohm.
1 Meg Ohm
750,000 Ohm.
750,000 OVirn.
R«mele
Kit Number
CGI 0-70
CGI 0-71
CGI 0-72
CGI 0-73
CG with "02" feature SPDT Output
•I*
•-02" fe.ture eppliei to the CG reley end it .n 8 pin plug-in rel.y
with SPOT output "D4" feeture oppliet to either CG or CGSOO reliyt
and li either *n 11 pin plug-in reUy (CG) or 11 terminal mieh.ne
tool relay cut* (CGSOO) with DPDT cutout.
MOUNTING
The "CG" timer will plug into any standard
octal base, even one wired for a relay,
where a time delay is needed. The Eagle
PDC-190 base is recommended as it pro-
vides screw terminals for wiring connec-
tions.
When the timer is mounted horizontally and
vibration is present, the CGI 0-84 latch can
be used to positively lock the relay in Its
socket.
CGSOO with "04" (Mture DPDT Output.
IMPORTANT Le*d* to Remote Potentiometer ire ivtceptible t* triniient
veltaget which could cause the Timer to malfunction To prevent the
effects of troniientt, it ii recommended th»t the leidi to th« Polentio-
r be oither twilled or ih.elded The ihield thould fae connected
o the i
MACHINE TOOL CAS I
-------
BULLETIN 327
PLUG-IN FLEXQPULSS
(HO 100 SETHIS)
CJ
C
, t , Close* and opens contacts repeatedly os long
trs tho timer Is energized.
FEATURES
• Two 10 Amp. sing)* pole double throve switches.
* Timer can bo adjusted anytime during tlmo cycle and w!!l
Immediately pick up now jetting.
• Time rango of unit conlrollod by synchronous motor thus elim-
mtnal ng complicated gear changing.
• Stainless steel directional control mechanism gives *est proven
life of over 10 million operations.
• Color keyed knobs and dial for easy, accurate reading and
sating.
• Cycle Progress Pointer allows for check* on progress at anytime.
* HG100 offers a wide selection of cycle ranges.
» Plug-In feature provides Instant Interchange-ability.
The HG Series Flexopulse hat 2 time scales on the dial. A btaclc
A synchronous unf-directlonal motor drives the unit through ore*
cliion pouring. Infant reversfrg of the un!t is obtained by posi-
-tivo mechanical action. The plug-In Cyct-flox case provides fiexi-
bility end neat appearan:e.
SPECIFICATIONS
Standard Time Ranges
UH!H
KMhti
H0100AA
HG10IA6
H0102A4
HG103A6
HC 104 Aft
HG.03A*
HO106A*
HG107A6
HG10BA6
HG109AA
HG110A4
HO111AA
»UI
•.«(•
30 SM.
40 5«.
TiOSec.
JMIn.
19 Mtn.
30 MIn.
60 MIn.
130 MIn.
SHn.
tO Hn.
30 Hn.
WHr*.
Mldmra
liMl*l
,3 S«.
ISic.
3S«.
5£*c.
IOS«.
30 5*c.
1 MIn.
2 Mint
SMn.
lOM'fi.
30 MIn.
60 MIn.
hpMrt
lti*t*(T
±,15Ste.
ft .3S«.
±.755«.
:tl.55«.
± 3S«.
± 9S.r.
± IBS.c.
± 45 See.
il.iMln.
± 3 MIn.
± 9Min.
± 10 MIn.
M*T >•*!!
Iwllikrt
J5«.
15t<.
3 I.e.
3S*c.
lOS.t.
30 SM.
1 Mtn.
2 MIn.
5 MIn.
10 Mtn,
30 MIn.
60 MIn.
Accuracy
ft of! % of Dial.
Electrical Rating
1 JO Volt, 50 Cycl« 120 Volt, 60 Cycl«
240 Volt, 50 Cycle 340 Volt, 60 Cycle
Contact Slafinns
10 Amp, 120 volts AC and S Amp, 240 volrt
AC roststjvo load.
Mechanical life 10,000,000 operations.
Switch life 250,000 under 10 Amp, 120 VAC
resistive lood 1,000,000 under S Amp. 120
VAC roslstlvo load.
Temperature Rango
-20'to+ 140'F.
Endoiuras and Accessories
Refer to Cycl-Flcx lection of Bulletin 5500.
Dimension;
Refer to page 2,
BULLETIN 321
PLUG-IN FLEXOPULSE
(HO 100 SERIES)
OPERATING INSTRUCTIONS
OFF ,..„ ON
SETTING 0 SETT! MO
To seti Move the brack pointer to the desired "OFF"
setting and the blue pointer to the desired "ON" setting.
The »um of these "ON" and "OFF" Intervals cannot
exceed the total time of one scale. Switch contacts are
tripped open or closed each time the Indicator pointer
passes "0." When the Indicator pointer Is In the "OFF"
scale to the left of "0" contacts 4-3 and contacts 6-8
are closed and 4-5 and 6-7 areiopftfl. When the Indi-
cator pointer Is In the "ON" scale to the right side of
"0" contacts 4-5 and 6-7 ore closed and 4-3 and 6-8,
• | TERMINAL ARRANGEMENT
tan X Nfvr* 4 (OMTACTS SHOWN
IN *W POSITION
are open. The Indicator pointer must travel to the pre-
set limit and bock to "0" to complete me total "ON"
or "OFF" interval. The two switches can operate to-
gether or be set to provide a dwelt interval or overlap
between "ON-OFF" switching. Refer to the standard
time range chart under specifications for the maximum
dwell interval far each time range. Figure 3 Illustrates
the path of the indicator pointer and the switch adlon
each time the zero point Is passed. Figure 4 Illustrates
the terminal location on the rear of the unit case.
CT»
MOUNTING DIMENSIONS
DRILL AND TAP FOUR
HOLES FOR 8-33 SCREWS
(INCLUDED W/T1MER)
DUST AND
OIL PROOF ONE PIECE
TIMER CASE
U.S. Government Printing Office: 1977—766-501/41 Region No. 6
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