ABB CM-SFS.21 Instrucciones De Servicio página 11

Operating principle
The current window monitoring relays CM-SFS.2 can be used
for the simultaneous monitoring of over- ">I" and undercurrents
"<I" in single-phase AC or DC systems. Depending on the
configuration, one c/o contact each Y or both c/o contacts
in parallel Z can be used for the over- and undercurrent
monitoring. The current to be monitored (measured value) is
applied to terminals B1/B2/B3-C. Open X or closed-circuit
principle W as well as an adjustable ON A or OFF tripping
B delay are selectable.
ON-delayed A current window monitoring with parallel
switching c/o contacts Z:
If the measured value exceeds resp. drops below the adjusted
threshold value before the set start-up delay T
output relays do not change their state.
If the measured value exceeds resp. drops below the adjusted
threshold value when T is complete, the tripping delay T
S
starts, when A is configured. If T
measured value is still exceeding resp. below the threshold value
minus resp. plus the fixed hysteresis (5%), the output relays
energize X /de-energize W.
If the measured value exceeds resp. drops below the threshold
value plus resp. minus the hysteresis and the latching function
is not activated U, the output relays de-energize X / energize
W. With activated latching function V the output relays remain
energized X and de-energize only, when the supply voltage
is interrupted / the output relays remain de-energized W and
energize only, when the supply voltage is switched off and then
again switched on = Reset.
OFF-delayed B current window monitoring with parallel
switching c/o contacts Z:
If the measured value exceeds resp. drops below the adjusted
threshold value when the set start-up delay T
output relays energize X / de-energize W, when B is
configured, and remain in this position during the set tripping
delay T .
V
If the measured value exceeds resp. drops below the threshold
value plus resp. minus the fixed hysteresis (5%) and the latching
function is not activated U, the tripping delay T
, the output relays de-energize X /
After completion of T
V
energize W, provided that the latching function is not activated
U. With activated latching function V the output relays
remain energized X and de-energize only, when the supply
voltage is interrupted / the output relays remain de-energized
W and energize only, when the supply voltage is switched off
and then again switched on = Reset.
When Y is adjusted on the device, the functionality is
equivalent to the one described above. There is only to
consider that in this case, instead of both output relays, only
one output relay each will be switched.
">I" = 11 -12 /14 ; "<I" = 21
15 16 18
is complete, the
S
is complete and the
V
is complete, the
S
starts.
V
-22 /24
25 26 28
Function diagrams
Current window monitoring, 1 x 2 c/o Z
V
ON-delayed A without latching U
Current window monitoring, 1 x 2 c/o Z
VI
OFF-delayed B without latching U
Current window monitoring, 1 x 2 c/o Z
VII
ON-delayed A with latching V
Current window monitoring, 1 x 2 c/o Z
VIII
OFF-delayed B with latching V
Current window monitoring, 2 x 1 c/o Y
IX
ON-delayed A without latching U
Current window monitoring, 2 x 1 c/o Y
X
OFF-delayed B without latching U
Current window monitoring, 2 x 1 c/o Y
XI
ON-delayed A with latching V
V
Current window monitoring, 2 x 1 c/o Y
XII
OFF-delayed B with latching V
Supply voltage A1-A2
1
2 Threshold value max.
3 Hysteresis
Measured value
4
5 Hysteresis
6 Threshold value min.
Open-circuit principle X
7
8 Output relay 1
9 Output relay 2
green LED
1 0
red LED
11
yellow LED
12
Closed-circuit principle W
1 3
If the adjusted „threshold value max." minus the hysteresis is
< „treshold value min." plus the hysteresis, all LEDs flash
synchronously. The function of the output relays remains
unchanged.
English
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