Fail-Safe - ABB RD3M Manual

Functions
Fail-safe → incorporated in the device (positive safety device) When no
current is input to the RD3 device, the output contacts number 10 11 12
will switch as shown in the figure below.
R
RD3
ON
7 8 9 10 11 12
FAIL SAFE
OUTPUT Relay
TRIP
Contact status when the device is switched off:
7 8 9 10 11 12
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BB_76x88mm_Rd3M_rev4.indd 18 19/09/11 11:02