Function of the guard locking – EUCHNER CETx-AS-xxx-CB-xxx (Multicode) User Manual
Page 8
Operating Instructions Safety Switch
CET.-AS-...-CB-...
8
Function of the guard locking
Version CET3-AS,
guard locking by spring force with door monitoring output
The lift tappet is pressed into the locked position by the force of the spring for the
guard locking pin in the actuator and unlocked electromagnetically by the safety
switch.
The guard locking solenoid is switched by software via AS-Interface output bit D0.
The guard locking functions in accordance with the closed-circuit current principle.
The guard locking cannot be opened directly if the guard locking solenoid is switched
off by means of AS-Interface output bit D0. The door can be opened directly if
the guard locking solenoid is switched on by means of AS-Interface output bit D0.
Closing safety guard and activating guard locking
The lift tappet is pushed down by the actuator. The door monitoring contact and
the solenoid monitoring contact are closed. The complete safety code sequence
is sent via AS-Interface input bits D0 to D3.
Deactivating guard locking
Switching the guard locking solenoid off via AS-Interface output bit D0 extends the
lift tappet and raises the actuator's guard locking pin over the edge of the recess.
The half-sequence is sent via AS-Interface input bits D0 and D1 in every bus cycle.
Opening safety guard
Opening the safety door moves the actuator out of the operating distance. The
values 0, 0, 0, 0 are continuously sent via AS-Interface input bits D0 to D3.
Version CET4-AS,
guard locking by solenoid force with door monitoring output
Important:
The safety guard can be opened immediately in the event of interruption of the
solenoid power supply! Usage only in special cases in accordance with strict
evaluation of the accident risk (see DIN EN 1088 (1995), section 5.5)!
Example: If the risk of accidental locking inside a safety guard during a power
failure is higher than the risk of ineffective guard locking.
The guard locking operates in accordance with the open-circuit current principle.
The lift tappet is held in locked position by electromagnetic force and released by
spring force. The guard locking solenoid is switched by software via AS-Interface
output bit D0.