ENERGY STAR for Set-top Boxes
Test Procedure
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This document is being proposed for addition to C380-08: Test procedure for the
measurement of energy consumption of set-top boxes (STBs) for purposes of
testing and qualifying products under:
(1)	ENERGY STAR Program Requirements for Set-Top Boxes - Version
2.0; and
(2)	ENERGY STAR Program Requirements for Cable, Satellite, and
Telecom Service Providers - Version 1.0.
All requirements for qualifying to the ENERGY STAR requirements are contained
herein.
5 Duty Cycle Workload Testing Procedure
5.1 Background
The purpose of this section is to provide a workload-based test procedure centered on the actions
of the user and the practical output of STBs when placed in situ. These are meant to mimic
general actions and general conditions of STBs when used by the average user and are not
meant to represent all conditions for all possible box functions and user scenarios.
5.1.1. Definitions
For purposes of this section (5 Duty Cycle Workload Testing Procedure), the definitions contained
in (1) ENERGY STAR Program Requirements for Set-Top Boxes - Version 2.0, and (2) ENERGY
STAR Program Requirements for Cable, Satellite, and Telecom Service Providers - Version 1.0
supercede those in section "3 Definitions and abbreviations" of C380-08 Test procedure for the
measurement of energy consumption of set-top boxes (STBs).
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5.2 Preparation
5.2.1 Measurement of Energy Consumption
For purposes of this workload-based test procedure, the following portions of section 4 of C380-
08 as amended, shall be followed.
4.1	General
Average power shall be measured from the AC power source to the equipment being
tested.
4.2	Test conditions
4.2.1 General
Unless otherwise specified, measurements shall be made under test conditions and with
equipment specified below.
4.2.3	Test room
The tests shall be carried out in a room that has an air speed close to the UUT of <0.5
m/s, and the ambient temperature shall be maintained at 23°C ± 5°C throughout the test.
The UUT shall be tested on a thermally non-conductive surface
4.2.4	Test voltage
An AC power source shall be used to provide input voltage and frequency of 115± 1% at
60 Hz to the UUT.
The Total Harmonic Distortion (THD) of the supply voltage when supplying the UUT in
the specified mode shall not exceed 2%, up to and including the 13th harmonic. The peak
value of the test voltage shall be within 1.34 and 1.49 times its RMS value.
4.2.5	Test leads
All leads used in the test set-up shall be of a sufficient gauge and length in order to avoid
the introduction of errors in the testing process.
Note: For further guidance, see Table B.2, "Commonly used values for wire gages and
related voltage drops" in IEEE 1515.
4.4 Test equipment
4.4.1 General
The following should be considered when selecting test equipment:
(a)	an oscilloscope with a current probe, to monitor AC line current waveform,
amplitude, and frequency;
(b)	a true rms volt meter, to verify voltage at the input of the unit being tested (optional if
AC source output is sufficiently accurate); and
(c)	a frequency counter, to verify frequency at the input of the unit being tested (optional
if AC source output is sufficiently accurate).
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4.4.2	Calibration
Test instruments shall be calibrated annually to traceable national standards to ensure
limits of error in measurement no greater than ± 0.5% of the measured value over the
required bandwidth of the output.
4.4.3	True power watt meter
4.4.3.1	Crest Factor
A true power watt meter, with accuracy and, resolution in accordance with 4.4.2, and
4.4.3.4 and sufficient bandwidth , and crest factor rating appropriate for the waveforms
being measured, shall be used.
The selected watt meter's crest factor rating shall be capable of reading the available
current waveform without clipping the waveform.
The peak of the current waveform measured during SLEEP and ON states for the UUT
shall determine the crest factor rating requirement and the appropriate current range
setting.
The full-scale value of the selected current range multiplied by the crest factor for that
range shall be at least 15% greater than the peak current to prevent any measurement
error.
4.4.3.2	Bandwidth
The current and voltage signal shall be analyzed to determine the highest frequency
component (harmonic) with a magnitude greater than 1% of the fundamental frequency
under the test conditions. This shall determine the minimum bandwidth of the test
instruments.
The meter shall be capable of sampling at a minimum of one second intervals.
4.4.3.3	Frequency response
A watt meter with a frequency response of at least 9 kHz shall be used, which accounts
for harmonics up to the 50th.
Note: Electronic equipment can cause harmonic waveforms that lead to inaccuracies in
power measurements.
4.4.3.4	Resolution
The power measurement instrument shall have a resolution of:
•	0.01 W or better for power measurements of 10 W or less;
•	0.1 W or better for power measurements of greater than 10 W up to 100 l/l/;
and
•	1 W or better for power measurements of greater than 100 l/l/.
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5.2.2	General
The box and test conditions should be prepared according to section 5.2.1 above.
a.	Begin the test by connecting all relevant A/V connectors.
b.	Next plug the box into the power source and let the unit sit for 15 minutes as the unit
initializes and comes to a ready state.
c.	Do not attach external devices that are not required for operation and/or that will not be
used with the device under normal operation.
d.	For signal source input, ensure that the box is connected to the input source and the
input source conforms to the source signal requirements below
e.	Connect the UUT to a display device (e.g. TV) via the applicable interface(s) supported
by the UUT (e.g. composite video output).
f.	If the UUT supports conditional access system control, then provision the UUT as
applicable for the UUT type (e.g. Cable, Satellite, Telcocom, or IP STB).
g.	Functions to disable: WiFi (unless WiFi is the primary network connection), VOIP and
data services (those exposed to the user for external use such as broadband services)
h.	Source Signals
a.	All Cable STBs interacting with Conditional Access (CA)system data via DOCSIS
Set-top Gateway (DSG) orSCTE-55 as applicable for the product
b.	All Telcocom QAM/IP STBs interacting with CA system data via SCTE-55 and/or
via an applicable LAN technology (e.g. Multimedia Over Coax - MoCA).
c.	All IP STBs interacting with CA system data via applicable LAN technology (e.g.
IEEE-802.3, Multimedia Over Coax - MoCA)
d.	STBs with POD/CableCard - encrypted content is decrypted by POD/CableCard
e.	All Satellite STBs - interacting with CA system via LNB and POTS modem
f.	All Terrestrial STBs - ATSC signal from a live source.
5.2.3	Duty Cycle Specific Test Conditions
a.	Remote: In all cases, user input should be accomplished with the remote in cases where
the unit ships with one, otherwise the unit's face controls should be utilized. In cases
where the functionality needed is not on the remote, then for that particular function the
face mounted controls should be utilized.
b.	Reset the meter after each test.
c.	When tuning to a broadcast video source, this is defined as one tuner acquiring an
encrypted digital video service, where the video service is rendered on all analog
audio/video output (e.g. RF modulated, S-Video, composite and component) and on all
SPDIF audio outputs (if equipped).
d.	If the UUT uses Smart card or POD technology for conditional access system control,
then insert the applicable card into the UUT prior to applying power.
i.	Reference Channels:
a.	[A] Standard Definition network TV (minimum 480i)
b.	[B] Live/Recorded Sporting channel. When the box is HD-capable, this channel
should be the HD version, (minimum 480i in SD, 720p in HD)
c.	[C] Standard Definition news channel, i.e., 24 hour news channel, (minimum
480i)
5.2.4	Other Specific Test Conditions
The following additional test conditions apply.
a.	Satellite Low Noise Block (LNB): incremental power required to operate the LNB(s), if
drawn from the STB, may be subtracted from the power measurements. It is preferable
that all LNB power drawn be supplied separately. Otherwise, the amount subtracted must
be clearly noted on the Qualified Product Information (QPI) form.
b.	Functions to Disable: WiFi (unless WiFi is the primary network connection), VOIP and
Data services (those exposed to the user for external use such as broadband services)
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5.3 Active Tests
5.3.1	Live TV (PTv)
a.	To begin the active portion of the test, press the button on the remote, if one is shipped with
the unit, responsible for turning on the tuner and/or tuning to a live TV signal. If there is no
"on" button and the unit's tuner is designed to be on continuously, then ensure that the tuner
is in a state where it is tuned to live TV.
b.	Proceed to change the channel on the tuner, to Reference Channel A as a starting point.
c.	Begin to measure average power at this point and continue for 5 minutes.
d.	After 5 minutes, switch the channel to Reference Channel B and continue to measure
average power. If the device is an HD device, select an HD stream for Reference Channel B
e.	After ten minutes, switch the channel to Reference Channel C. If the UUT has one or more
Additional Tuners as defined in the ENERGY STAR specification then with the second tuner
acquire Channel A and render in a window embedded in the primary window while the
primary tuner displays in the primary picture window Channel C In the case of multiple sizes
available to the user, the one closest to the size of % the screen size will be chosen. In the
case where no picture-in-picture capability exists, simply record the second channel in the
background instead.
f.	Wait 5 minutes and note the average power used during the test. Total test time should be
twenty minutes.
g.	When testing a DVR or unit with similar functionality, the video must be paused 5% of the
time, in fast forward 10% and in rewind 10% during each Channel test above, all the while the
raw video feed is being buffered. However, this does not increase the overall test times.
5.3.2	Recording Live TV (PRecord)
a.	Tune to the Reference Channel.
b.	Begin the test by starting the meter
c.	Begin recording Channel A for 5 minutes.
a. Note that for certain devices it may be more accurate to create a series of
programmed back-to-back recording sessions to avoid HID prompts. This is
allowed.
d.	Switch to Channel B for 10 minutes.
e.	Switch to Channel C for 5 minutes.
f.	Stop the meter and note the average power value for the past 20 minutes of recording
time.
g.	Save the recordings for the Playback test.
h.	In the case of a DVR or unit with similar functionality, a second tuner, if available on the
UUT, must be engaged in recording during the entire time.
5.3.3	Playing Back Recorded TV (Ppiayback)
a.	Tune to Reference Channel A.
b.	Begin the test by starting the meter
c.	Press the button on the remote to bring the menu containing previously recorded
recordings onto the screen.
d.	Begin watching the first recording from Channel A.
e.	When done delete the recording (if prompted to do so simply select the affirmative
prompt).
f.	Proceed to the recordings menu and select the second recording.
g.	Begin watching the second recording from Channel B.
h.	When done delete the recording (if prompted to do so simply select the affirmative
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prompt).
i. Begin watching the second recording from Channel C.
j. When done delete the recording (if prompted to do so simply select the affirmative
prompt).
k. Stop the meter and note the average power value for the playback time.
I. When testing a DVR or unit with similar functionality, the video playback must be paused
5% of the time, in fast forward 10% and in rewind 10% during each Channel test above,
all the while the raw video feed is being buffered. However, this does not increase the
overall test times.
m. In the case of a DVR or unit with similar functionality, a second tuner, if available on the
UUT, must be engaged in recording during the entire time.
5.3.4	Removable Media Playback Test (Ppiayback)
a.	To begin the media playback test, tune to Reference Channel A.
b.	Start the meter.
c.	Press the button to activate the media playback functionality.
a. Note that if the playback function is automatically started when the door for the
removable media is opened, this is sufficient.
d.	If applicable, open the media door, insert the media and if applicable, close the media
door.
e.	Either allow the media to automatically begin playback or begin playback by using the
menu or "play" button on the remote.
f.	Playback the recording for 20 minutes.
g.	Press "stop" on the remote.
h.	Eject the media if applicable.
i.	Stop the meter and note the average power for the test.
5.3.5	Removable Media Record Test (PRecord)
a.	To begin the media record test, tune to Reference Channel A.
b.	Start the meter.
c.	If applicable, open the media door, insert the media and if applicable, close the media
door.
d.	Press the button to activate the media record functionality.
e.	Either begin recording by using the menu or "play" button on the remote.
f.	Record the recording for 20 minutes.
g.	Press "stop" on the remote.
h.	Eject the media if applicable.
i.	Stop the meter and note the average power for the test.
j. If the unit is HD recording capable, perform the test with an HD stream and average the
value of both tests.
5.4 Inactive Tests
5.4.1	Sleep Test (Psieep)
a.	To begin the inactive system tests, run through at least the Watching Live TV test in
5.3.1.
b.	Press the power/standby button on the remote to place the system into its lower power
state.
c.	Soon thereafter start the meter.
d.	After 20 minutes take the reading of average power off of the meter.
5.4.2	Auto Power Down (P Aut0 pd)
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a.	Place the unit in a state where it is tuned to live TV.
b.	Allow the STB to auto power down.
c.	Verify that the device went into the expected lower power state.
d.	Soon thereafter start the meter.
e.	After 20 minutes take the reading of average power off of the meter.
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