Rockwell Automation 1425 PowerMonitor Wireless 250 - Manual (Page 29)

Rockwell Automation Publication 1425-UM001A-EN-P - January 2012 29
Hardware Installation Chapter 2
Rogowski Coil
1. Observe the correct phase assignment of Rogowski coils with respect to
the voltage phase connections.
Refer to the wiring diagram for the applicable PowerMonitor W250
model. If phase assignment and polarity are not correctly observed, the
PowerMonitor W250 unit will produce incorrect energy data.
2. Verify that the arrow (3) points in the direction of current flow from the
supply (line) to the load.
3. Close the Rogowski (2) coil around the cable (1).
Be sure that the coil is well locked (fully inserted until a click is heard).
Figure 22 - Rogowski Coil Mounting
The Rogowski coil can be oriented freely around the cable/conductor. It
does not need to be attached. The position of the conductor within the
Rogowski coil does not affect the accuracy more than 0.5%.
ATTENTION: When installing a Rogowski coil, take care not to kink, pinch,
twist, or sharply bend the coil. Applying such mechanical stress to the coil may
reduce the accuracy of the PowerMonitor W250.
Load Side
Generator
Side
Load Side
Generator
Side
2
1
4
3
3
IMPORTANT The arrow indicating the current direction must be inside the loop (3) when
closed as shown.