Basler BE1-CDS220, Instruction Manual

Page: 145 / 476

BE1-CDS220 Reporting and Alarm Functions 6-27
TRIP CIRCUIT MONITOR
The trip circuit voltage and continuity monitoring function
monitors the trip circuit for voltage and continuity. If a
breaker is closed or the 86 Lockout relay is reset and no
voltage is detected across the trip contacts, then either the
fuse supplying the circuit is blown or there is a loss of
continuity in the trip coil circuit.
The trip circuit monitor function obtains the breaker status
from a programmable setting, which is set using the <status>
parameter in the SL-CKTMON command. The detector
circuit used by the trip circuit monitoring function is
programmable using the <monitor> parameter in the SL-
CKTMON command. Program one of the contact sensing
inputs (e.g. IN6) as the trip circuit monitor input. The input circuit draws less than two milliamperes of
current through the trip coil when the breaker is closed. Figure 6-13 shows the trip circuit monitor logic.
If the relay detects that the breaker is closed and no voltage is sensed across the terminals of the open
output contact after the appropriate coordination time delay (approximately 500 milliseconds), the relay
sets an alarm bit in the programmable alarms function and sets the CKTMON BESTlogic logic variable to
TRUE.
Figure 6-14 shows a typical connection diagram for the circuit monitor. Also, see Section 8, Application,
Application Tips, for instructions on how to program a close-circuit monitoring function in BESTlogic. In
this example, OUT1 is tripping the lockout relay (86T) and IN3 is monitoring the lockout relay status.
Trip
Other
Relays
+
-
CDS
IN6
CDS
OUT1
R
86a
CDS
IN3
Status
86a
86T
Monitor
D2850-13
06-25-99
TC
+
-
Trip Circuit
Relay Circuit
Figure 6-14. Trip Circuit Voltage and Continuity Monitor
CAUTION
Applications that place other device inputs in parallel with the breaker trip coil
may not perform as desired. The connection of other devices in parallel with the
trip coil causes a voltage divider to occur when the breaker or trip circuit is open.
This may cause false tripping of the other devices and prevent the BE1-CDS220
trip circuit monitor from reliably detecting an open circuit. Contact Basler Electric
for advice on this application.
The circuit monitor sensing element has the same rating as the power supply
voltage. If the trip circuit voltage is significantly greater than the power supply
voltage (for example, when using a capacitor trip device), the user should
program the BE1-CDS220 to use one of the other output relays for tripping. In
this situation, the trip circuit monitor function will not be available.
Figure 6-13. Trip Circuit Monitor Logic
D2850-12
12-14-05
CIRCUIT
MONITOR
STATUS
CKTMON
Mode
0 - Disable
1 - Enable
MONITOR