Signal Outputs (So); Rtd/Analog Inputs - ABB REF 54 Series Technical Reference Manual, General

1MRS750527-MUM
5.1.8.4.
5.1.9.
Feeder Terminal
Technical Reference Manual, General
If the power outputs BIO2_7_PO3... BIO2_7_PO6 are used as single-pole outputs,
the object to be controlled, for example a circuit breaker, is electrically connected in
series with the two relay contacts to provide sufficient current breaking capacity, see
the following figure.
e.g.
BIO2_7_PO3...
BIO2_7_PO6
Fig. 5.1.8.3.-2 Single-pole power outputs (PO)

Signal outputs (SO)

The signalling relay outputs (BIO1_5_SO_) are not heavy-duty outputs and thus
they cannot be used for controlling for example a circuit breaker. Available relay
contacts are either Normally Open or Normally Open/Normally Closed type (NO or
NO/NC), see the following figure. These outputs can be used for alarming and other
signalling purposes.
NO/NC
e.g.
PS1_4_SO1
Fig. 5.1.8.4.-1 Signal outputs (SO)

RTD/analog inputs

The REF 541 and REF 543 feeder terminals equipped with an RTD/analog module
(RTD1) have eight general purpose analog inputs for DC measurement. The RTD/
analog inputs are galvanically isolated from the feeder terminal power supply and
enclosure. However, the inputs share a common ground.
+
CB
-
NO
e.g.
BIO1_5_SO1
REF 54_
PO2conn_n
nonc_b
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