PNOZ s4
Operating Manual PNOZ s4
21396-EN-21
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Function description
}
Single-channel operation: no redundancy in the input circuit, earth faults in the start
circuit and input circuit are detected.
} Dual-channel operation without detection of shorts across contacts: Redundant input cir-
cuit, detects PNOZ s4
– earth faults in the start and input circuit,
– short circuits in the input circuit and, with a monitored start, in the start circuit too.
}
Dual-channel operation with detection of shorts across contacts: Redundant input cir-
cuit, detects PNOZ s4
– earth faults in the start and input circuit,
– Short circuits in the input circuit and, with a monitored start, in the start circuit too,
– Shorts across contacts in the input circuit.
} Automatic start: Unit is active once the input circuit has been closed.
} Manual start Unit is active once the input circuit and the start circuit are closed.
} Monitored start with falling edge: Unit is active once
– the input circuit is closed and then the start circuit is closed and opened again.
– the start circuit is closed and then opened again once the input circuit is closed.
} Monitored start with rising edge: Unit is active once the input circuit is closed and
once the start circuit is closed after the waiting period has elapsed (seetechnical details).
} Start with start-up test: The unit checks whether safety gates that are closed are
opened and then closed again when supply voltage is applied.
} Increase in the number of available instantaneous safety contacts by connecting contact
expander modules or external contactors/relays;
A connector can be used to connect 1 PNOZsigma contact expansion module.