Siemens S5-135U/155U appendix Setting the Fan Monitor

Central Controllers and Expansion Units Power Supply Units

Setting the Fan Monitor

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You can set jumper F-R on the power supply units to choose whether or not the air flow monitor should switch off the internal supply voltage Vo/p (5 V) when a fan fails.

SJumper F-R closed: Vo/p shutdown (signaled by contact)

SJumper F-R open: no Vo/p shutdown (signaled by contact)

If one or both fans are at standstill, the signaling relay drops out (monitor output). The ªFan Faultº LED lights up simultaneously.

SRelay contacts 2-1 closed: fan running

SRelay contacts 2-3 closed: fan failure

Relay contacts 2-3 closed; this is also the normally closed contact during power OFF (failsafe).

Caution

If an immediate shutdown is not possible, jumper F-R must be opened. In this case you must ensure that the power supply is switched off after 60 s at the latest. This can be achieved with a time relay, for example. It avoids overheating and destruction of modules.

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C79000-G8576-C199-06