Accuracy Testing
MAXsys Elite Meter
The accuracy testing for the Elite meter is done through the transmit “LED” of the optical port
on the face of the meter. The optical port is located on the lower left hand side of the meter face
and the left “LED” is the transmit LED and is located on the left side of the port. The LED has 9
modes of operation. Optical communications (type 7 protocol), Watt hour, Var hour,
Compensated Watt hours Comp. 1, Compensated Var hours Comp. 1, Compensated Watt hours
Comp. 2, Compensated Var hours Comp. 2, Compensated Watt hours Comp. 3 and Compensated
Var hours Comp. 3. The modes can be changed using MAXcom under the test mode screen. The
meter does not need to be put into test mode to change the LED modes. The mode of operation
can be seen on the meter display using the menu system. The user would enter the menu system
using the buttons (E) on the face of the meter. They would then select “communications” from
the list of menu items. This will take the user to a sub menu where they can select the optical
port. To select the optical port the user will select the “more ports” option that will bring up
another menu with “optical port”. After selecting “optical port” the screen will display the “Cal
Pulse” mode .
When testing for meter accuracy it is recommended that no test should be run for less than 30
seconds. The 30 second test is recommended to reduce timing errors between the test equipment
and the meter. The following examples are for a Form9S, 120 volt meter with a Kh of 1.0 being
tested a rated voltage and a test current of 2.5 and 0.25 amps.
Full Load
10 Rev.
40 seconds
Power Factor 05 Rev.
40 seconds
Light Load
02 Rev.
80 seconds
When testing TLC accuracy the values meter is normally tested at the rated secondary value of
the instrument transformer.
The following examples are for a Form 9S, 120 volt meter with a Kh of 1.0 that is connect to
instrument transformers, VTR=7200:120 and CTR=1200:5. The tests are normally run at rate
voltage (120 volts) and a test current of % and 0.5 amps.
Full Load
20 Rev.
40 seconds
Power Factor 10 Rev.
40 seconds
Light Load
04 Rev.
80 seconds
