EATON ELECTRICAL
59
Predictive Diagnostics
Important Note: In the firmware version 2.07 ONLY detected phase shift MUST be
manually corrected by subtracting the detected number from 360Deg. For
example, display shows 135. The correct number for all following operations will
be 360-135=225Deg!
Phase Reference Option
Additional Phase Shift
PT Phase A
0
PT Phase B
-120
PT Phase C
-240
PT Phase A-B
+30
PT Phase C-B
+90
RVS sensor of Cutler-Hammer
0
External signal from Coupling Capacitor on Phase A
+90
Precaution
#12 terminal input is a very sensitive and it has high impedance. It is affected by power frequency noise.
Below are some hints that may identify incorrect phase angle measurement:
•
InsulGard displays dashes with some consistency in firmware version 2.00 and higher or 0 in
older versions. Signal is likely close to zero.
•
InsulGard reads 357
0
most of time in firmware pre-version 2.XX. Signal is too high.
•
Phase angle varies on more than +/-10
0
. High noise content in the signal.
Check jumper position and reference signal magnitude in any of these cases!
6.2.2 External synchronization
The table below presents phase angles for most common synchronization options. These numbers
should be manually entered from IG keypad or IG software at InsulGard startup and commissioning.
External Synchronization Signal
Phase Shift
PT Phase A
0
PT Phase B
+240
PT Phase C
+120
PT Phase A-B (Open Delta)
+30
PT Phase C-B (Open Delta)
+90
Coupling Capacitor on the Phase A
Pre-Revision 1
+90
Coupling Capacitor on the Phase A
Revision 1
0
RVS sensor of Cutler-Hammer
0
