External device monitoring – Banner Safety Mat Monitoring Modules User Manual

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• A transformer with isolated windings
• A distribution system with multiple branch circuits (capable of diverting energy of surges)
• A capacitance capable of absorbing energy of surges
• A resistance or similar damping device capable of dissipating the energy of surges

When switching inductive ac loads, it is good practice to protect the Safety Module outputs by installing appropriately-sized arc suppres-
sors. However, if arc suppressors are used, they must be installed across the load being switched (e. g., across the coils of external
safety relays), and never across the Safety Module’s output contacts (see WARNING, Arc Suppressors).

External Device Monitoring

To satisfy the requirements of Control Reliability (OSHA and ANSI), Category 3 and 4 of ISO 13849-1 (EN 954-1), the Master Stop
Control Elements (MSCs) must each offer a normally closed, forced-guided (mechanically linked) monitor contact. Connect one normally
closed monitor contact from each master stop control element in series to S31 and S32.
In operation, if one of the switching contacts of either MSC fails in the energized condition, the associated monitor contact will remain
open. Therefore, it will not be possible to reset the Safety Module. If no MSC-monitor contacts are monitored, a jumper must be installed
between terminals S31-S32, as shown in the hookup drawings. It is the user's responsibility to ensure that any single failure will not result
in a hazardous condition and will prevent a successive machine cycle.

SM-xA-5A Safety Mat Monitoring Modules

P/N 122364_Web
rev. C