Honeywell Fema DWAM Series Assembly And Operating Instructions Manual page 17

1.5.1 Maximum pressure limitation with external interlock
When the interlock circuit shown above is used, the requirements according to DIN 57 116 /
VDE 0116 are fulfilled if the electrical plant, such as contactors or relays, correspond to the external
interlock circuit VDE 0660 or VDE 0435 respectively.
DWR = pressure monitor
T1 = STOP
T2 = START
S = signal (as required)
K1 = relay with self-hold
Safety
circuit
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