Calculating The Kilowatthour-Per-Pulse Value - Siemens ACCESS 9340 Reference Manual

PMCM-9340D-0208
2/2008

Calculating the Kilowatthour-Per-Pulse Value

© 2008 Siemens Energy & Automation, Inc. All Rights Reserved.
This section shows an example of how to calculate kilowatthours per
pulse. To calculate this value, first determine the highest kW value
you can expect and the required pulse rate. In this example, the
following assumptions are made:
•
The metered load should not exceed 1600 kW.
•
About two KY pulses per second should occur at full scale.
Step 1: Convert 1600 kW load into kWh/second.
(1600 kW)(1 Hr)
(1600 kWh)
------------------------------ -
(1600 kWh)
------------------------------------ -
3600 seconds
X = 1600/3600
Step 2: Calculate the kWh required per pulse.
0.444 kWh/second
------------------------------------------------ -
2 pulses/second
Step 3: Adjust for the KY initiator (KY will give one pulse per two
transitions of the relay).
0.2222 kWh/second
---------------------------------------------------- -
2
Step 4: Round to nearest hundredth, since the meter only accepts
0.01 kWh increments.
Ke
= 1600 kWh
X kWh
= ----------------------- -
1 hour 1 second
X kWh
= ----------------------- -
1 second
= 0.444 kWh/second
= 0.2222 kWh/pulse
= 0.1111 kWh/pulse
= 0.11 kWh/pulse
ACCESS 9340 and 9360 Meters
Chapter 5—Input/Output Capabilities
EN–67