5-262
L60 Line Phase Comparison System
GE Multilin
5.6 CONTROL ELEMENTS
5 SETTINGS
5
CIRCUIT MONITORING APPLICATIONS:
Some versions of the digital input modules include an active voltage monitor circuit connected across form-A contacts. The
voltage monitor circuit limits the trickle current through the output circuit (see technical specifications for form-A).
As long as the current through the voltage monitor is above a threshold (see technical specifications for form-A), the “Cont
Op 1 VOn” FlexLogic operand will be set (for contact input 1 – corresponding operands exist for each contact output). If the
output circuit has a high resistance or the DC current is interrupted, the trickle current will drop below the threshold and the
“Cont Op 1 VOff” FlexLogic operand will be set. Consequently, the state of these operands can be used as indicators of the
integrity of the circuits in which form-A contacts are inserted.
EXAMPLE 1: BREAKER TRIP CIRCUIT INTEGRITY MONITORING
In many applications it is desired to monitor the breaker trip circuit integrity so problems can be detected before a trip oper-
ation is required. The circuit is considered to be healthy when the voltage monitor connected across the trip output contact
detects a low level of current, well below the operating current of the breaker trip coil. If the circuit presents a high resis-
tance, the trickle current will fall below the monitor threshold and an alarm would be declared.
In most breaker control circuits, the trip coil is connected in series with a breaker auxiliary contact which is open when the
breaker is open (see diagram below). To prevent unwanted alarms in this situation, the trip circuit monitoring logic must
include the breaker position.
Figure 5–131: TRIP CIRCUIT EXAMPLE 1
Assume the output contact H1 is a trip contact. Using the contact output settings, this output will be given an ID name; for
example, “Cont Op 1". Assume a 52a breaker auxiliary contact is connected to contact input H7a to monitor breaker status.
Using the contact input settings, this input will be given an ID name, for example, “Cont Ip 1", and will be set “On” when the
breaker is closed. The settings to use digital element 1 to monitor the breaker trip circuit are indicated below (EnerVista UR
Setup example shown):
Trip coil
52a
UR-series device
with form-A contacts
I = current monitor
V = voltage monitor
DC–
827073A2.CDR
H1a
H1b
H1c
I
V
DC+
Summary of Contents for L60
Page 10: ...x L60 Line Phase Comparison System GE Multilin TABLE OF CONTENTS ...
Page 57: ...GE Multilin L60 Line Phase Comparison System 2 27 2 PRODUCT DESCRIPTION 2 3 SPECIFICATIONS 2 ...
Page 58: ...2 28 L60 Line Phase Comparison System GE Multilin 2 3 SPECIFICATIONS 2 PRODUCT DESCRIPTION 2 ...
Page 482: ...6 26 L60 Line Phase Comparison System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6 ...
Page 554: ...10 8 L60 Line Phase Comparison System GE Multilin 10 2 BATTERIES 10 MAINTENANCE 10 ...
Page 674: ...B 110 L60 Line Phase Comparison System GE Multilin B 4 MEMORY MAPPING APPENDIX B B ...
Page 704: ...C 30 L60 Line Phase Comparison System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Page 720: ...E 10 L60 Line Phase Comparison System GE Multilin E 1 PROTOCOL APPENDIX E E ...
Page 732: ...F 12 L60 Line Phase Comparison System GE Multilin F 2 DNP POINT LISTS APPENDIX F F ...
Page 742: ...H 8 L60 Line Phase Comparison System GE Multilin H 3 WARRANTY APPENDIX H H ...