MPG-1C Wireless Meter Pulse Generator (con't)
Communication LEDs
Upon power-up, the YELLOW comm LED should light indicating that the RAVEn dongle is correctly inserted, initialized and
communicating with the MPG-1C's processor. Within about approximately 45 - 60 seconds, the GREEN comm LEDwill
blink each time a valid transmission is received from the meter. As long as valid transmissions are received by theRAVEn
dongle and successfully relayed to the MPG-1C's processor, the Green comm LED will blink about once every 8-9 seconds.
If the Green comm LED does not blink, that is an indication that the data transmissions from the meter are not being
received, may be corrupted, or in some manner are not valid transmissions. If the Green comm LED has been blinking
reliably every 8-9 seconds for some time, then stops for a while and then restarts again, this indicatesthat transmissions are
intermittent and sporatic, or generally means there is a problem in the RAVEn's ability to receive data reliably from the
meter. To correct this, change the proximity of the MPG-1C to the meter, move it closer to themeter if possible and
eliminate any metalic obstructions between the meter and the MPG-1C. Also check to make sure that any walls or barriers
between the MPG-1C and the meter have as little metal in them as possible. In some applications you may need line-of-
sight.
Pulse Outputs
Outputs can be configured to bein the Toggle (Form C) mode or the Fixed (Form A) mode. Generally speaking, the Form
C mode can be used with either 2-Wire or 3-Wire Pulse receiving devices, while the Form A mode uses only a 2-Wire
interface to the downstream (receiving) pulse device. The choice would depend on the application and the desired pulse
format that the receiving device preferstosee.
If the RAVEn is reliably receiving data from the meter and passing it on to the MPG-1C's processor, thenyou should see the
Red and Green output LED's toggle each time the selected pulse value is reached, and the processor generates a pulse. If
the pulse output value is too high and pulses are too slow, then select a lower pulse value using the Pcommand.
If pulses are being generated too rapidly, select a higher pulse output value using the Pcommand. The maximum number
of pulses per second in the toggle mode is approximately 10, which means that the output's open and closed times are
about 50mS each in toggle mode. If the calculation by the MPG-1C's processor is for pulse output timing that exceeds 15
pulses per second, the MPG-1C will light the RED comm LED, indicating an overflow error, and that the pulse value is too
small. It is "latched" on so that the next time you look at it this RED LED will be lit. In this way, youcan quickly determine if
a pulse output value is too small. In the optimum application, pulses would not exceed more than one or two pulsesper 8
seconds at full scale demand. This allows a very even and "normal" pulse rate that as closely as possible resembles an
actual KYZ pulse output from the meter.
The MPG-1C will "spread out" the pulses over the next 10 second period if a high enough watt-hour valueisreceived in a
transmission to require that more than one pulse is generated. For example, suppose you have the Output Pulse Value of
10 wh selected. The next 8 second transmission yields 24 wh have been used. Since 24 watt-hours exceeds the 10 watt-
hour setting, two pulses must be generated. The first 10wh pulse will be generated immediately. About 3-5 seconds later
the second 10wh pulse will be generated. The remainder of four watt-hours stays in the accumulated energy register (AER)
awaiting the next transmission and the energy value of that transmission to be added to the contents of the AER. Another
example: Assume 25 wh/p Output Pulse Value. Let's say the next transmission is for 130 watt-hours. 130 is greater than
25, so 5 pulses will be outtputted over the next 7 seconds, approximately one each 1.4 seconds (7 seconds/ 5 = 1.4
seconds). The remainder of 5 wh will stay in the AER awaiting the next transmission. Some trial and error may have to be
done for any particular building since pulse rates will change depending on maximum load.
Overranging the Output
As previously mentioned, if there are too many pulses calculated to be outputted in a 6-7 second interval than the MPG-1C
can generate given the timing constraints, the MPG-1C will light the RED Comm LED. In this situation, simply increase the
output pulse value using the Pcommand. This LED is intended to notify the user that some pulses have been lost and a
larger pulse value is needed. As load is added to a building over time, there is a greater likelihood that this may occur,
especially if the pulse value is small. Be sure to consider this if/when you add load to the building. If an error condition
occurs, set the Output Pulse Value for a Wh value that is double the current pulse value. Remember tochange the pulse
constant of your receiving device as well, since pulses will now be worth twice the value. Cycle power to the MPG-1C to
reset the RED Comm LED after increasing the pulse value.
