Wire Fail Detection - Deif CGC 400 Reference Book

CGC 400 DRH 4189340786 UK

7.17 Wire fail detection

If it is necessary to supervise the sensors/wires connected to the multi-inputs and analogue inputs, then it is
possible to enable the wire break function for each input. If the measured value on the input is outside the
normal dynamic area of the input, it will be detected as if the wire has made a short-circuit or a break. An
alarm with a configurable fail class will be activated.
Input
4-20 mA
Pt100
Pt1000
RMI Oil, type 1
RMI Oil, type 2
RMI Temp, type 1
RMI Temp, type 2
RMI Temp, type 3
RMI Fuel, type 1
RMI Fuel, type 2
RMI configurable
Level switch
Principle
The illustration below shows that when the wire of the input breaks, the measured value will drop to zero.
Then the alarm will occur.
Input signal
(mA, °C,b, %)
Upper failure
limit
Lower failure
limit
DEIF A/S
Wire failure area
< 3 mA
< 82.3 ohm
< 823 ohm
< 1.0 ohm
< 1.0 ohm
< 4.0 ohm
< 4.0 ohm
< 0.6 ohm
< 0.6 ohm
< 1.0 ohm
< lowest resistance
Only active if the switch is open
Wire failure
Wire failure
Wire break
Normal range
4-20 mA
-
-
-
-
-
-
-
-
-
-
t
Additional functions
Wire failure area
> 21 mA
> 194.1 ohm
> 1941 ohm
> 195.0 ohm
> 195.0 ohm
> 488.0 ohm
> 488.0 ohm
> 97.0 ohm
> 97.0 ohm
> 195.0 ohm
> highest resistance
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