A2.2 Comparing Led Pulses With Substandard Meter Pulses; A3 Checking Meter Registration Accuracy From Register Advances; A3.1 Using The 'Dial Test' Values On The Meter Display - Elster A1140 User Manual

A2.2 Comparing LED pulses with substandard meter pulses
This method may be used where the test equipment has the facility to calculate meter errors
based on the pulse output from a substandard meter. It will be necessary to set the pulse value of
the meter under test (shown on the meter nameplate) into the meter test equipment.
The duration of each test must be at least 60 seconds
The number of LED pulses should be greater than:-
Itest x V x Pf x N x K
1000 x 60
A3 Checking Meter Registration Accuracy from Register Advances
For these methods the advance of the meter register is used rather than the LED Test Indicator.
A3.1 Using the 'Dial Test' values on the meter display
Meters may be set to show cumulative kWh and kvarh registers
with increased resolution by using Power master Unit instructions
via the optical or RS232 port. Dial test displays can be programmed
to 0, 1, 2, 3 or 4 decimal places.
Import
The display resolution will revert to normal when a further appropriate instruction (Setting power
down count to zero) is received, or after a programmable number of power cycles.
What you will need
A suitable supply and load or a meter test bench.
Substandard meter with a kWh (kvarh) display.
For each measured quantity:
1. Connect the meter and substandard meter to the supply
2. Instruct the meter to show register to suitable dial test resolution
3. Record initial values of the meter and substandard meter registers
4. Apply a suitable load to cause a significant register advance
5. Switch off the load to stop the register advancing. Leave the supply connected
6. Record the final register readings, compute the advances and compare the meter advance
with the substandard advance
Operating & Maintenance Instructions
Itest = Test current
V = System voltage
Pf = Power factor of test load
N = Number of system elements
K = LED pulse value, impulses/kWh
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