User Manual

PNOZ s1
Operating Manual PNOZ s1
21393-EN-07
4
Safety features
The relay meets the following safety requirements:
} The circuit is redundant with built-in self-monitoring.
} 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 on-off cycle.
} The unit has an electronic fuse.
Block diagram/terminal configuration
Input
A1 A2

Power
Reset/
Start
S34

Y32
K1
K2
13
23
24
14
Interface
expansion
unit
Centre: Front view with cover, right: Front view without cover
Function description
} Single-channel operation: no redundancy in the input circuit, earth faults in the reset
and input circuit are detected.
} Automatic start: Unit is active once the input circuit has been closed.
} Manual reset: Unit is active once the input circuit is closed and then the reset circuit is
closed.
} Increase in the number of available instantaneous safety contacts by connecting con-
tact expander modules or external contactors/relays;
A connector can be used to connect 1 PNOZsigma contact expander module.