Datalogic SG4-RB2-050-OO-N, Instruction Manual

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6.7 OVERRIDE FUNCTION FOR SG4-RB-
…-W MODELS
This function allows forcing a Muting condition when machine reset is necessary, even if one or more beams
are interrupted by passing material.
The purpose is to clear the protected area of any material accumulated consequently to a failure in the
working cycle.
For example, if a pallet stops in front of the protected area, the conveyor may not restart as the ESPE (that
has one or more interrupted beams) opens the OSSD outputs and will not permit the controlled area
clearance.
The activation of the Override function allows this operation.
6.7.1 Override function activation
•
Override function cannot be activated when the light curtain is in SAFE state or NORMAL
OPERATION state, but only when OVERRIDE condition is met. OVERRIDE condition is
met when the light curtain is in SAFE state and at least one MUTING beam is obscured.
•
When the requirements for the activation are met, a signaling is provided onto the LED
display in order to inform users that an override is possible and required (see Figure 40).
Figure 40
Two input lines are provided for the activation of the override function, Override1 and Override2 that must be
connected to +24 Vdc and to 0 Vdc respectively by means of two normal open contacts (see section 5
–
“ELECTRICAL CONNECTIONS AND CONFIGURATION”).
Standard requires the use of spring return hold-to-run devices or secure momentary action push buttons,
located so that it will not be possible to enter the hazardous zone whilst maintaining the action on devices.
Override function can be actuated closing both contacts: whatever contact can be activated first.
The maximum out-of-sync interval time allowed is 400 ms, while the minimum one is 0 ms, as shown in the
timing diagram of Figure 42.
While override is actuated, the integrated lamp will be blinking.
State of Override is signaled by the Override Lamp integrated on the top of receiver side (see Figure 41).
When the Override function is ON the LAMP output signal is driven.
Figure 41
During the installation take care to place the lamps in an as visible as possible position.
If both the internal lamp and the external lamp are broken and/or not connected, the Override request
causes the opening of the safety contacts, the device is blocked in SAFE state and the failure is signalled
(see par. 8.2)
Override function will automatically terminate when one of the following condition will be given:
•
all the muting sensors are de-actuated (*);
•
the pre-determined time limit has expired;
•
the requirements for actuation are not met any more (at least one override input line
is deactivated).