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Functional description
As soon as the press tool reaches the BDC, the start muting sensors SM1 and SM2 are activated. When activated within a time
frame of maximum 10 s, a new muting sequence will be started. The end muting sensors EM1 and EM2 must get de-activated
as soon as the press tool starts its closing stroke. The muting sequence gets terminated as soon as the first of the end muting
sensor EM1 or EM2 is de-activated. All muting sensors SM1, SM2, EM1 and EM2 must be de-activated before starting a new
valid muting sequence.
In any case, the muting sequence will be interrupted after the maximum selected muting time has elapsed. If an object remains
accidentally in the detection field of the safety device, an external temporary manual muting (customer supplied) may be used to
evacuate the detection field (see chapter "Temporary Manual Muting").
For the functional diagram, refer to the application example 2.
APPLICATION EXAMPLE 5: MUTUAL EXCLUSION FUNCTION IN A ROBOT AREA
Mutual exclusion function with 2 safety devices and an enabling contact
Mechanical fences
Acknowledge P/B
Position switch
FF-SYA Safety light
FF-SYA Safety light
curtain 1 (robot)
curtain 2 (operator)
IMPROPER OPERATOR DETECTION (USA and Canada)
Using light curtains for the access detection of an operator combined with an acknwowledge push button may not meet US and
Canadian requirements and regulations. Use presence sensing devices instead to permanently detect the presence inside the
hazardous area. Always comply with local requirements, including lockout (as per 29CFR1910.147).
Failure to comply with this instruction could result in death or serious injury.
Application description
A robot and an operator regularly access the same hazardous area in order to carry out operations.
The mutual exclusion principle consists in:
• allowing the operator access to the hazardous area only when the robot is outside of it,
• allowing the robot access to the hazardous area only when the operator is outside of it and has acknowledged exiting the area.
The mutual exclusion system is composed of the following elements:
• the FF-SRM200P2 muting module,
• safety device 1 (e.g. FF-SYA safety light curtain 1) monitoring the access of the robot into the area,
• safety device 2 (e.g. FF-SYA safety light curtain 2) monitoring the access of the operator into the area,
• an optional safety device (e.g. safety switch) monitoring the robot position, before it is detected by safety light curtain 1,
• an acknowledge push-button located outside of the area.
The functional principle of the mutual exclusion consists in not allowing the activation of the safety devices for the operator and
the robot at the same time. When the operator is entering the area activating safety light curtain 2, the access is memorised in
the module. After leaving the area the operator needs to push the acknowledge push-button to confirm his exit. This push-button
must be located outside the area with a clear view to the hazard.
If the robot activates safety light curtain 1 before the operator has pushed the acknowledge push-button, the hazard will be
stopped through the safety relay outputs of the FF-SRM200P2 muting module.
The hazard will also be stopped if safety light curtain 1 is activated and the operator attempts to enter the area actuating safety light
curtain 2.
In order to increase safety (especially when the operator is likely to work close to safety light curtain 1 (robot) without keeping the
required safety distance), safety may be increased by installing an additional safety sensor (e.g. safety switch) to monitor and
anticipate the robot position.
If used, both the auxiliary safety device AND the safety light curtain 1 must have their sensing fields free (= voltage is applied to
the module inputs S11 to S14, S31 and S32), in order to allow the operator to enter the hazardous area. As soon as the robot is
detected by AT LEAST ONE of the robots safety devices (light curtain 1 or additional safety switch), the operator is not allowed
to enter the hazardous area without stopping the hazard.
17
107111-11-EN FR26 GLO 503 Printed in Germany
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