CIRCUTOR CVM-NRG96 Series (Available until stocks) - Manual (Page 36)

CVM-NRG96
M9817250120-03-05A
36
FAQ’s
1. The CVM-NRG96 analyzer, once cabled and connected is seen to give a
correct voltage and current reading, but shows negative values for active
power (generation).
This is an error with the cabling for the current transformer secondaries; the
direction of the transformer current has to be respected as shown in the
connection diagram. The current transformers have a two face primary; the
current must pass from P1 to P2 giving the result in secondary (S1 and S2) of
5 amps.
The error stems from:
a) The current transformers have been incorrectly installed. As a
result it gives the direction of the current as passing from P2 to P1;
to resolve this problem, the current transformer does not have to be
dismantled and installed again, but the transformer secondary (S1
and S2) just has to be inverted.
b) The connection of the current secondaries in the current
transformers have been incorrectly connected; to resolve this
problem just connect the S1 transformer secondary to the S1 on
the analyzer and the S2 on the current transformer to the S2 on the
analyzer.
2. The CVM-NRG96 analyzer, once cabled and connected, is seen to give an
incoherent Power factor and Cos φ III reading (-0.01 or similar).
This is again a current transformer and voltage phase connection error phase
L1 (R), must correspond to the current transformer installed in phase L1 (R);
phase L2 (S), must correspond to the current transformer installed in phase L2
(S); and phase L3 (T), must correspond to the current transformer installed in
phase L3 (T).
This connection is clearly shown on the back of the analyzer.