BECKWITH ELECTRIC Syncrocloser M-3410A, Instruction Book

Page: 63 / 225

M-3410A Instruction Book
2–20
2.8 Commissioning Checkout
During field commissioning, check the following to
ensure that the CT and VT connections are correct.
1. If using M-3810A IPScom ® for
Windows™, then select the RELAY/
MONITOR drop down menu and choose
Secondary Status (see Figure 2-17) .
2. If using IPScom for Palm OS ® , then
select Monitor/Secondary Status (see
Figures 2-20 through 2-21).
3. Compare these voltages and currents
with actual measurements using a meter.
If there is a discrepancy, check for loose
connections to the rear terminal block of
the unit. If line-ground -to-line-line voltage
selection is used, the voltages displayed
are
S S
S S S
3 times the line-ground voltages
applied.
4. The positive sequence voltage should
be V
POS
y V
A
y V
B
y V
C
or V
AB
y V
BC.
5. The negative sequence voltage should
be V
NEG
y 0.
6. The zero sequence voltage should be
V
ZERO
y 0.
If the negative sequence voltage shows
a high value and the positive sequence
voltage is close to zero, the phase
sequence is incorrect and proper phases
must be reversed to obtain correct phase
sequence. If the phase sequence is
incorrect, frequency and power related
functions will not operate properly.
If positive, negative and zero sequence
voltages are all present, check the
polarities of the VT connections and
change connections to obtain proper
polarities.
7. The positive sequence current should
be I
POS
y
I
a
y
I
b
y
I
c
.
8. The zero sequence current should be
I
ZERO
y
0A. If a significant amount of
negative or zero sequence current
(greater than 25% of I
A
, I
B
, I
C
), then
either the phase sequence or the
polarities are incorrect. Modify
connections to obtain proper phase
sequence and polarities.
Q Q Q Q Q
NOTE: The CT and VT polarities can be easily
verified by observing the oscillographic
waveforms using optional M-3801D
IPSplot
®
PLUS
Oscillograph Analysis
software or with third party COMTRADE
Format Viewer software.
9. The sign for Real Power should be
positive for forward power and negative
for reverse power. If a sign does not
agree with actual conditions, check the
polarities of the three CTs and/or the
PTs (for forward and reverse power
conventions see Figures 2-11 through
2-15).
10. Ensure all Error Codes are cleared (see
Appendix C,
Self-Test Error Codes ).
If relay INPUT and OUTPUT tests are desired, then
see Section 5.2, Diagnostic Test Procedures, for
details.