ABB REQ650 - Four Step Residual Overcurrent Protection (EF4 PTOC)

I
E
D
C
L
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C
M
D
T
r
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p
C
B
5
2
a
C
B
R
E
A
D
Y
BR
SC
ST
SRY
To test
set
+
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ANSI04000202-1-en.vsd
BI
BI
ANSI04000202 V2 EN
Figure 18: Simulating the CB operation by a bi-stable relay/breaker simulator and
manual switches
The following manual switches are used:
• Switch or push-button to close (SC)
• Switch or push-button to trip (ST)
• Switch for CB ready condition (SRY)
If no bi-stable relay or breaker simulator is available, replace it with two self-reset
auxiliary relays and use a self-holding connection.
1MRK 505 293-UUS A Section 6
Testing functionality
107
Commissioning manual