Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 Installation Instructions, PRIOR to Firmware rev. 3.0 - Manual (Page 21)

Publication 1404-IN007D-EN-P - October 2004
Powermonitor 3000 21
Voltage and Current Inputs
Voltage Input and PT Selection
The Powermonitor 3000 is designed to connect directly to power
system rated up to 600 volts line-to-line (347 volts line-to-neutral).
Higher system voltages require the use of user-supplied PTs. Typical
secondary voltage on a PT is 120V ac. Select the PT primary voltage to
match the nominal voltage of your power system.
Connect user-furnished short circuit protection between the power
system and the Powermonitor 3000. If PTs are used, install the
user-furnished short circuit protection on the high-voltage side of the
PTs.
Current Inputs and Current Transformer (CT) Selection
The current input on the Powermonitor 3000 is designed for a 5 amp
nominal current signal. User-supplied CTs are required to connect
your power system to the input of the Powermonitor 3000. Select the
CT primary current to match the nominal current of your power
system.
The shorting terminal block should be located adjacent to the
Powermonitor 3000 Master Module so that it is readily accessible
should service be needed. Use #14 AWG (2.5 mm
2
) wire for the short
run between the Powermonitor 3000 and the shorting terminal block.
Use wiring of #12 AWG (4 mm
2
) or larger between the shorting
terminal block and the CT so that the additional load of the wiring
does not overload the CT and reduce its accuracy.
ATTENTION
Never open a current transformer secondary circuit
with primary current applied. Wiring between the
CTs and the Powermonitor 3000 should include a
shorting terminal block in the CT secondary circuit.
Shorting the secondary with primary current present
allows other connections to be removed if needed.
An open CT secondary with primary current applied
produces a hazardous voltage, which can lead to
personal injury, death, property damage of economic
loss.