Pilz PNOZ c2 24VDC 2n/o - Manual (Page 6)

PNOZ c2
Operating Manual PNOZ c2
22212­EN­02 6
Safety features
The relay meets the following safety requirements:
} The circuit is redundant with built­in self­monitoring.
} The safety function remains effective in the case of a component failure.
} The correct opening and closing of the safety function relays is tested automatically in
each on­off cycle.
Block diagram/terminal configuration
*Insulation to the non­marked area: Protective separation (overvoltage category III),
Insulation of relay contacts against each other: Basic insulation (overvoltage category III),
protective separation (overvoltage category II)
Function description
When the supply voltage is supplied, the "POWER" LED illuminates. The unit is ready for
operation when the start circuit is closed or when a start contact is opened and closed
again in the start circuit.
} High signal at input circuit (e.g. light guard nor interrupted): The safety contacts are
closed and the semiconductor output transmits.
} Low signal at the input circuit (e.g. light guard is interrupted): The safety contacts are
open and the semiconductor output is de­energised.
} Dual­channel operation without detection of shorts across contacts: redundant input cir­
cuit, detects earth faults in the start and input circuit.
} Automatic start: Unit becomes active as soon a there is a high signal at the input circuit.
} Monitored start: Unit is active once there is a high signal at the input circuit and then the
start circuit is closed.
} Increase in the number of available instantaneous safety contacts by connecting con­
tact expander modules or external contactors.