If the building on which you are using the MPG-2 has an "Instrument-Rated" electric meter (an electric meter that has
current transformers), AND the local utility has not included this multiplier in the programming of the meter (which is
normally the case), you will have to program the Meter Multipler into the MPG-2's operating parameters. To check out
whether or not this is needed, look at the serial output using the MPG-2's programming USB port using the SSI-UP, and
convert the demand data in hexideciminal format to to decimal data. If the kW demand is not correct, then the meter is
sending a Secondary value, meaning that the multiplier is not included.
5.1
Multiplier (CT Ratio or CT x PT Ratio) (Con't)
Determine the Multiplier of the facility's electric meter. If the meter is a self-contained meter (no external current
transformers), the multiplier is 1. The default external multiplier in the MPG-2 is one (1), so you can skip this step. If the
utility's Zigbee transmission to the dongle includes the correct CT/PT multiplier value
(Primary
value), you can skip this
step also. This is very rare on instrument-rated metering implementations however, since most utilities do not want to
program the multiplier into the meter due to conflicts with the billing process. If you are looking at the serial data received
from the meter, you will be able to see what internal multipier is being sent in every transmission. This will be in
hexideciminal format. What you're looking for is whether this is 1 or something else besides 1. If, for instance, the multipler
is a decimal 160, it will be transmitted by the meter to the dongle as a hexideciminal "A0". If the multiplier
is
one(1), (and
this is the standard) AND
you know
that that the meter's external multipler is something other than 1, you will have to
program the correct external multiplier into the MPG-2 so that the true energy value, and thus the kW demand is correct.
To change the multiplier in the MPG-2, enter the correct multiplier in the
Meter Multiplier
field. If you are done entering
information you can press the "Send" box and the multiplier will be sent to the MPG-2 and will show correctly now in the
Meter Multipler field.
The USB serial link will return the current multiplier stored in the MPG-2, along with all other system settings. The
maximum multiplier is 99999 and must be an integer (whole) number.
5.2
Programming the Output Pulse Value
The output pulse value is the number of watt-hours that each pulse is worth. This is represented by the
Pulse Value
field.
The MPG-2 can be set from 1 Wh to 99999 Wh per pulse. Select a pulse value that you think will be appropriate for your
application. A good starting point is 100 wh/pulse. You can adjust it up or down as needed. Larger facilities will require a
larger pulse value to keep from overranging the MPG-2's registers or the maximum number of output pulses per second.
Enter 100 in the Pulse Value field and press <Send> to set the Output Pulse Value at 100 wh/pulse. The Pulse Value on
the SSI-UP will now show the correct value:
----------------------------------------
Pulse Value: 100 watt-hours
----------------------------------------
5.3
Set Output Mode
For one direction operation, set the MPG-2's Output Mode to
Normal
mode (kWh delivered). Set the MPG-2's mode to the
Signed
mode (kWh delivered or received) if desired for a distributed energy resource(DER) application such as solar or
wind. In the Normal mode only positive energy (delivered) is displayed and pulses generated. In the Signed mode,
bidirectional energy (delivered or received) can be displayed and pulses generated for each mode individually. Use the
Output Mode field to select desired mode. The Normal mode is the default.
For Normal Mode:
Set the Mode field to Normal and press <Send> to set the Output Mode to Normal Mode. The serial link to the MPG-2 will
return:
----------------------------------------
Normal
----------------------------------------
For Signed Mode:
Set the Mode field to Signed and press <Send> to set the Output Mode to Signed Mode. The serial link to the MPG-2 will
return:
----------------------------------------
Signed
----------------------------------------
MPG-2 Programming
