Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 User Manual, PRIOR to Firmware rev. 3.0 - Manual (Page 27)

1 Publication 1404-UM001D-EN-E - October 2004
Chapter
3
Powermonitor 3000 Operations
The Powermonitor 3000 is a microprocessor-based electrical power-
and energy-measuring device. It connects to the user’s three-phase or
single-phase AC power system directly or through instrument
transformers (PTs and CTs). It converts instantaneous voltage and
current values to digital values, and uses the resulting digital values in
calculations of voltage, current, power, energy, etc. You may access
the resulting metering values manually using the Display Module or
automatically using communications with an external device or
application.
The basic operations of the Powermonitor 3000 include the following:
• Metering functionality
• Operational and status indication
• Operation of the Display Module
• Display Module menus and parameter structure
• Setup and configuration using the Display Module
• Data monitoring using the Display Module
• Issuing commands using the Display Module
Other Powermonitor 3000 features such as communications, setpoint
operations, I/O operations, data logging, oscillography, harmonics,
sag/swell detection, load factor calculation and transient detection will
be covered later in this manual.
Metering Functionality The Powermonitor 3000 performs calculations on scaled, digital
voltage and current values. Signals connected to the voltage and
current inputs are sampled and their instantaneous values are
converted to digital values in an analog-to-digital (A/D) converter
section. These values are scaled according to configured PT Primary,
PT Secondary, CT Primary and CT Secondary parameters, and
evaluated according to the configured Wiring Mode parameter.
Metering results are available for display on the Display Module, in
the communications data tables and for use in setpoint programming
and data logging. Table 3.1 provides a summary of measurements
produced in each Powermonitor 3000 model, and notes which
measurements you may view using the Display Module.