Setting The Fan Monitor - Siemens S5-155U System Manual

Setting the fan monitor

System Manual
C79000-B8576-C199-03
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 U (5 V) when a fan fails.
A
• • Jumper F-R closed: U
shutdown (signalled by contact)
A
• • Jumper F-R open: no U
A
If one or both fans are at standstill, the signalling relay drops out
(monitor output). The "Fan Fault" LED lights up simultaneously.
• • Relay contacts 2-1 closed: fan running
• • Relay 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.
6ES5 955-3NA12 Power Supply Unit
shutdown (signalled by contact)
4
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