Rockwell Automation 1426 PowerMonitor 5000 Unit - Manual (Page 53)

Rockwell Automation Publication 1426-UM001F-EN-P - November 2013 53
Metering Chapter 4
Realtime_Update_Rate
This parameter specifies the averaging used and the update rate of metering
results to the data tables and setpoint calculations. You can select from the
following:
0 = Single cycle averaged over 8 cycles
1 = Single cycle averaged over 4 cycles
2 = 1 cycle with no averaging
Related Functions
• Voltage and Current Metering
• Power Metering
• Energy Metering
• Demand Metering
• Configuration Lock
• Data Logging
• Power Quality monitoring
Wiring Diagnostics The PowerMonitor 5000 unit provides a means for you to verify proper power
monitor connections and diagnose wiring errors. To meter power and energy
correctly, voltage and current inputs must be connected to the power circuit with
the correct phase rotation and polarity. Indications of wiring errors include the
following:
• Indication of negative real power (kW) on a load, or indication of positive
power on a generator
• Power factor outside the range of 45% lagging to 80% leading
• Very different power and/or power factor values on different phases
Wiring diagnostics operate on command in any wiring mode, and require a level
of measured current at least 5% of the nominal metering scale, or 250 mA of CT
secondary current.
The PowerMonitor 5000 unit calculates phase angles of voltage and current, and
checks these against three distinct ranges of system power factor:
• Range 1: lagging 97% to leading 89%. This range is for very high lagging or
significantly leading power factors. Examples of loads in this range include
data centers, over-excited synchronous motors, and circuits with power
factor correction.
• Range 2: lagging 85% to leading 98%. This range includes most industrial
circuits that range from lagging to slightly leading power factors, including
circuits feeding AC variable-frequency drives.
• Range 3: lagging 52% to lagging 95%. This range exhibits lower lagging
power factors. Examples include lightly-loaded motor circuits and DC
SCR drives.