AS40241

The CU1 is an on-delay timing unit designed to energize and thus unlock guard locking devices after a preset time delay expires. It can be used with power to unlock devices, like the Allen-Bradley Guardmaster Atlas, Spartan, 440G-MT, or TLS-GD2, on machines which have a run down cycle or do not stop immediately. It may also be incorporated into other parts of the safety related controls system, should a predictable, on-delay be required. A removable cover allows access to the AC power switch, the replaceable fuse, and the DIP switches & potentiometer which control the timing. Power to the CU1 can be either 24V AC/DC (+/ - terminals) or 110/230V AC (A1/A2 terminals). If 110V AC or 230V AC power is used, an internal switch must be set to the appropriate position.

The X1/X2 terminals are designed to monitor the performance of the contactors which isolate the power to the moving parts of the machinery. The timing can not begin until the X1/X2 loop is closed.

The X1/X2 loop must remain closed during the whole timing cycle. Opening the X1/X2 loop during the timing cycle causes the time to be reset to zero. If monitoring is not needed, the X1/X2 loop can be linked.

A typical operation starts with the safety outputs (13/14 and 23/24) open and the X1/X2 loop closed.