Standard measurement facilities
Standard three-phase wattmeter-meter CE7008
STANDARD MEASUREMENT FACILITIES
STANDARD THREE-PHASE WATTMETER-METER CE7008
1. Purpose and configuration
1.1. The standard three-phase wattmeter-meter CE7008, Specifications 4225-004-00229903-2004
(hereinafter-WM), is designed for verification and adjustment of three-phase and single-phase facilities
for measurement of active power and electric energy, of three-phase facilities for measurement of reactive
power and electric energy and also of facilities for measurement of ac strength and voltage.
WM can be used independently and as part of measuring sets for verification and adjustment of threephase and single-phase active energy meters and of three-phase reactive energy meters (hereinaftermeters).
WM is provided with the certificate of approval for the type of measurement facilities (RU.C.34.001.
A #504) and recorded in the State Register of measurement facilities under # 27558-04.
1.2. WM has 2 groups of the modes of operation:
 “With control of input signal parameters” – for independent use and for operation as part of a
measuring set;
 “Without control of input signal parameters”– recommended only for operation as part of the
measuring set with an apparent power source – programmable three-phase MK7006 or another
source, ensuring the required accuracy of specifying the input signal parameters.
The modes of operation included in the group “With control of input signal parameters”:

measuring active power;

measuring reactive power;

measuring ac voltage;

measuring ac strength;

determining the error of signal-phase and three-phase active energy meters;

determining the error of three-phase reactive energy meters.
The modes of operation included in the group “Without control of input signal parameters”:

measuring active power;

measuring reactive power.
1.3. WMs are manufactured:

with maximum current of 60A (hereinafter – “CE7008 60A”);

with maximum current of 100A (hereinafter – “CE7008 100A”);

with the limit of intrinsic relative error being equal to ±0.05% - in the measurement of active
power and ±0,1% in the measurement of reactive power (hereinafter–“CE7008-0.05/0.1”)
2. Specifications
2.1. WM measures active power in a single-phase circuit and determines the error of single-phase
active energy meters in the ranges with rated values of the quantities:

voltage (Vr),V
57.7; 230; 100; 400;

power factor (cos )
1.0; -1.0
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Standard measurement facilities
Standard three-phase wattmeter-meter CE7008
WM measures active power in a three-phase four-wire circuit and determines the error of three-phase
four-wire active energy meters in the ranges with rated values of the quantities:
 phase voltage (Vr),V
57.7; 230
 power factor (cos )
1.0; -1.0
WM measures active power in a three-phase three-wire circuit and determines the error of three-phase
three-wire active energy meters in the ranges with rated values of the quantities:
 line voltage (Vr),V
100; 400;
 power factor (cos )
1.0; -1.0
WM measures reactive power in a three-phase circuit and determines the error of three-phase reactive
energy meters in the ranges with rated values of the quantities:
 line voltage (Vr),V
100; 400;
 power factor (sin )
1.0; -1.0
The limits of admissible value of intrinsic relative error of measurement for active and reactive power
are listed in Table 1.
Table 1
Quantity
measured
Limits of admissible error value, %
CE 7008 – 0.05/0.1
active power
± 0.05
reactive power ± 0.1
The intrinsic relative error of measurement for active and reactive power is standardized at the values
of current strength, voltage and power factor listed in Table 2.
Table 2
Quantity
Range of values for
CE7008 60A
CE 7008 100A
current strength from 10 mA to 60 A
from 10mA to 100A
voltage
from 75 to 120% of Vr
0.5 lead −1 − 0.5 lag; [ - 0.5 lead ] – [-1] – [- 0.5 lag ]
cos , sin 
2.2. When operating in the modes “MEASURING POWER” and “DETERMINING ERROR”
with control of input signal parameters, WM makes measurement of voltage, ac strength, frequency
and angle of phase shift between current and voltage.
2.2.1. The limits of admissible intrinsic fiducial error of measurement for ac strength and voltage in
the modes “DETERMINING ERROR” and “MEASURING POWER” are equal to ± 0,1%.
The ranges of ac measurement, rated (Ir) and standardizing (Is) values are listed in Table 3. The
ranges of ac voltage measurement, rated (Vr) and standardizing (Vs) values are listed in Table 4.
Table 3
CE 7008 60A
CE 7008 100A
Measurement ranges, A
from 0.01 to 0.06
Ir, A
0.05
Is, A
0.06
Measurement ranges, A
from 0.01 to 0.06
Ir, A
0.05
Is, A
0.06
from 0.05 to 0.3
0.25
0.3
from 0.05 to 0.3
0.25
0.3
from 0.2 to 1.2
1
1.2
from 0.2 to 1.2
1
1.2
from 1 to 6
5
6
from 1 to 6
5
6
from 2 to 12
10
12
from 2 to 12
10
12
from 10 to 60
50
60
from 10 to 60
50
60
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Standard measurement facilities
Standard three-phase wattmeter-meter CE7008
from 10 to100
100
100
Table 4
Measurement ranges, V
from 10 to 69.3
from 15 to 120
from 35 to 276
from 60 to 480
Vr, V
57.7
100
230
400
Vs,V
69.3
120
276
480
2.2.2. The limits of admissible intrinsic absolute error of frequency measurement in the range from 45
to 65 Hz are equal to ±0.01 Hz.
2.2.3. WM makes measurement of an angle  of phase shift between the current and voltage, fed to a
measuring element (ME), in the range from 0 to 360, and indicates  value that is equal to , when
measuring active power, and (+90) - when measuring reactive power.
The limits of admissible intrinsic absolute error of phase shift angle measurement are equal to ±1.
The measurement error of phase shift angle is standardized at the following values of the quantities:

voltage – from 70 to 120% of Vr;

current strength – in the ranges listed in Table 3;

distortion factor of current-voltage curve sinusoidality is not over 1%.
2.2.4. WM makes computation of power factor (cos , sin  ) for signals applied to ME 1, 2 and 3.
The error of power factor determination is not standardized.
2.3. The limits of admissible intrinsic fiducial error of current strength measurement in the mode
“MEASURING AC STRENGTH” and of voltage measurement in the mode “MEASURING AC
VOLTAGE” are equal to ±0.1%.
The measurement ranges of alternating current, rated (Ir) and standardizing (Vs) values are listed in
Table 3. The measurement ranges of ac voltage, rated (Vr) and standardizing (Vs) values are listed in
Table 4.
2.4. In the modes “DETERMINING ERROR” WM determines error, checks shunt running absence
and checks the threshold of sensitivity for 1-6 meters of the same type with its gear ratio from 0.1 to
3600000 pulses per watthour (var hour).
2.3.1. The meter error is determined by comparing the values of electric energy, metered by WM and
the meter during the time of testing. The value of electric energy, metered by the meter during the time of
testing, is determined by the number of pulses coming in during this time to the frequency input of WM
from the telemetric meter output. The ranges of meter error determination, %, are:

from
-50.00 to 10.00;

from
-9.999 to 9.999;

from
-10.00 to 99.99.
The time of meter error determination is limited by the values of, s;
Tmax = (65535/F) where F is a pulse repetition rate at the frequency input of WM;
Tmin is the largest of two values: an introduced, in WM programming, minimum time of error
determination and an estimated time of error determination at which the error, due to discreteness of
energy measurement by WM, is sufficiently small.
The minimum time of meter error determination at the set load is specified within 1 − 99s.
The estimated time of error determination is computed from the results of power measurement with
regard for the chosen range of measurements.
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Standard measurement facilities
Standard three-phase wattmeter-meter CE7008
2.4.2. A check of shunt running absence and check of sensitivity threshold of the meter is performed
by comparing with the specified number of pulses, coming in from its telemetric output during the
specified time of test.
The results of meter checks are indicated as “Good” or “Reject”.
The ranges of specifying the quantities in WM programming:

for test time – from 1 to 65535s;

for maximum number of pulses that can be obtained from the meters during test time, when
checking shunt running absence, and for minimum number of pulses that must be obtained
from the meters during test time, when checking sensitivity threshold – from 0 to 99.
2.4.3. WM is provided with 6 frequency inputs for connecting the telemetric outputs of the electricity
meters verified. The frequency inputs of WM are galvanically isolated from each other and from the other
circuits.
The parameters of input signals:

shape–rectangular pulses of positive polarity;

high–level voltage - within 5-15V;

low–level voltage - not over 0.8V;

duration–no less than 67s.
2.5. An admissible value of additional error of WM, when temperature of ambient air departs from
normal to any within operating conditions of use, does not exceed ½ limit of an admissible value of
intrinsic error.
2.6. WM is provided with a transmitter. When operating in the modes “MEASURING POWER”, the
sequence of rectangular pulses, the repetition rate of which is proportional to the power measured, is
formed at the output of the transmitter.
The output of the transmitter (an optical coupler with an output “n-p-n” transistor, Vmax =15V,
Imax=10mA) is galvanically isolated from the measuring circuits of WM.
2.7. WM is controlled:

by operator from the control board on the front panel;

from an IBM – compatible personal computer (PC).
PC – WM communication is carried out over the RS232 interface. The data communication protocol
of PC and WM (instructions, sequence of transmission of WM control instructions from PC and sequence
of data transmission from WM to PC) is presented in the maintenance documentation.
When the operator exercises control from the control board, the gear ratio of the transmitter is
determined by the range of measurements and chosen by WM automatically.
When WM is as part of the measuring set, the control is exercised from PC and a gear ratio value can
be specified in the range from 1 to 9999999 pulses/watt-hour (maximum pulse repetition rate must be no
more that 50 kHz.
2.8. The settling time of the operating mode of WM is 15 minutes.
2.9. The maximum length of continuous operation of WM in the operating conditions of use is 10
hours (without regard for the settling time of the operating mode).
2.10. Choosing the range of measurements.
2.10.1. The range of measurements of the CE7008 60 A is chosen in its programming or in the process
of measurements without external switchings and without a break in the current circuit.
2.10.2. The range of measurements of the CE7008 100 A for voltage is chosen in its programming
without external switchings.
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Standard measurement facilities
Standard three-phase wattmeter-meter CE7008
2.10.3. The CE7008 100 A has two groups of measurement ranges of alternating current (ac) and
power.
The measurement ranges with Ir, being equal to 0.05; 0.25; 1; 5 and 10A, make up the first group
(inputs”(0-12)A”), and the measurement ranges with Ir, being equal to 50 and 100A, make up the second
group (inputs ”(10-100)A”).
The measurement ranges for current inside the groups are chosen without external switchings and
without a break in the current circuit.
To change from one group of the ranges to the other it is necessary to carry out external switchings of
the current circuits { inputs ”(0-12)A” and “(10-100)A”}.
2.11. When the power of WM is ON, its series circuits have program and circuit protection against
overloading. The circuit protection comes into action when current strength in any series circuit is over
1.7Ir {except for the range with Ir =Imax (60A or 100A)}. The program protection comes into action if a
measured value of current strength is over 1.3Ir or a measured value of power is more than 1.56(Vr×Ir)
even in one of the phases.
2.12. The total power, consumed by each parallel circuit of WM at the rated value of voltage and the
normal value of frequency, does not exceed 1 VA.
2.13. The total power, consumed by each series circuit of WM at Imax and the normal value of
frequency, does not exceed 10VA.
2.14. WM is powered from the ac mains, 220V, 50 Hz. The total consumed power of the power supply
circuit of WM does not exceed 100 V A.
2.15. WM size is not over, mm- 480×510×186
WM mass does not exceed 18 kg.
Standard three-phase wattmeter CE7008.
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