EMX Industries, Inc. Tech support: 216-834-0761 4/6
•Must use 6-35 VDC for pulse monitoring.
•The relay contacts labeled on the terminals and the references to them in these instructions are
shown in the energized state, no obstruction. (Dark ON setting –normally open (NO) contact closes
when the beam is unobstructed.)
•Pulsed configurations require current limiting in the operator. The IRB-MON will pulse 300Hz when
not obstructed and 0Hz when obstructed.
•DIP Switch 4 should be ON in virtually every configuration scenario.
When DIP Switch 4 is ON the relay will change state during a loss of power. This is sometimes referred
to as a “fail safe” mode. It is also sometimes referred to as Dark ON mode as the relay contact will be
in the closed position when under power and NOT obstructed.
•Dip Switch 4 is OFF in very rare installation scenarios. When Dip Switch 4 is OFF, the relay will function
in reverse. In addition, if DIP Switch 4 is OFF, during a loss of power the relay will
NOT change state during a loss of power. This is sometimes referred to as “fail secure” mode.
It is also sometimes referred to as Light ON (or Dark OFF) mode as the relay contact will be in the
open position when under power and NOT obstructed. WARNING: Leave DIP Switch 4 ON in all
normal operations and all UL 325 monitoring scenarios.
