PNOZ X2
Operating Manual PNOZ X2
1003353-EN-08
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Function Description
The safety relay PNOZ X2 provides a safety-oriented interruption of a safety circuit. When
supply voltage is supplied the "POWER" LED is lit. The unit is ready for operation when the
start circuit S33-S34 is closed.
} Input circuit is closed (e.g. E-STOP pushbutton not operated):
– Safety contacts 13-14 and 23-24 are closed, the unit is active.
– The LEDs "CH.1" and "CH.2" are lit.
} Input circuit is opened (e.g. E-STOP pushbutton operated):
– Safety contacts 13-14 and 23-24 are redundantly opened.
– The LEDs "CH.1" and "CH.2" go out.
Operating modes
} Single-channel operation: No redundancy in the input circuit, the PNOZ X2 detects
– earth faults in the input circuit,
– earth faults and short circuits in the start circuit.
} Dual-channel operation with detection of shorts across contacts: Redundant input circuit,
detects PNOZ X2
– earth faults in the start and input circuit,
– short circuits in the start and input circuit,
– shorts across contacts in the input circuit.
} Monitored start: Unit is active once the input circuit is closed and once the start circuit is
closed after the waiting period has elapsed (see Technical details [ 13]).
} Increase in the number of available contacts by connecting contact expandsion modules
or external contactors/relays.
Timing diagram
Legend
} Power: Supply voltage
} Start: Start circuit
} Input: Input circuit
} Output safe: Safety contacts
} t
1
: Switch-on delay
} t
2
: Delay-on de-energisation
} t
3
: Waiting period with a monitored start