Reer MZERO Installation, Use And Maintenance Manual page 79

STAND ALONE PROGRAMMABLE SAFETY CONTROLLER
Operation in the "Mandatory Gate Opening" mode
In this case, the user must NOT select the "Gate
not present" parameter and must select the
"Mandatory Gate opening" parameter.
The Gate input must always be connected to an
"E-GATE" input element (see the
E-GATE (safety gate
section on page 44) that verifies the status
device)
of the door/gate. NB: IN THIS OPERATING MODE
THE "GATE" INPUT MUST CONFIRM THE OPENING
OF THE GATE.
The Lock_Fbk input must always be connected to
a "LOCK FEEDBACK" input element (see the section on page 46) that verifies
LOCK FEEDBACK
the status of the guard lock electromagnet.
The UnLock_cmd input can be connected freely in the diagram and determines the request to
unlock the guard lock (when set to LL1).
The Output signal is LL1 (TRUE) if the safety guard is closed and locked. When an unlock command
is applied to the UnLock_cmd input, the Output signal is set to LL0 and the guard lock is unlocked
via the LockOut signal.
The Output signal can also be set to LL0 (FALSE) when error conditions are present (e.g. open
door with guard lock locked, Feedback Time exceeding the maximum allowed, etc.).
When the Unlock_cmd signal is detected, the LockOut signal unlocks the guard lock after the
UnLock Time, a parameter that can be defined by the user.
The time after which the electromagnet is activated depends entirely on the technical/physical
characteristics of the specific device and may therefore vary according to the type of guard lock
used. Thus, since the the LockOut signal controls the activation of this device, the status of the
Lock_Fbk feedback signal will change at different times, depending on the type of guard lock.
This variability can be avoided by changing the value of the Feedback Time parameter, which is the
maximum delay accepted by the "Guard_Lock" operator before the Lock_Fbk signal switches
status following a request to activate the electromagnet. Clearly, the following condition must be
met:
Feedback Time ≥ Electromagnet activation time
This will now be explained using a practical example.
8541403 • 19/07/2021 • Rev.1 79