Function description
Operating Manual PNOZ s50
1002194EN02
13
4
Function description
4.1
Introduction
The PWM relay PNOZ s50 is used for the safetyrelated shutdown of inductive loads.
It has two power outputs to activate two independent, inductive loads. Each power circuit is
switched independently by two inputs. Two feedback loops monitor the switch status of the
inductive loads. Two failsafe outputs signal the switch status of the inductive loads to the
higher level safety control system. A failsafe fault signal output signals any fault to a higher
level safety control system.
The device is configurable. All the parameters can be set via a rotary knob with pushbutton.
The state of the inputs and outputs, the configuration and any faults are shown on a dis
play. The configuration is stored on a chip card.
There is an integrated counter, which records the number of operations for each power cir
cuit.
Block diagram
A1
A2
Y20 Y21 Y22 Y23
Power
=
B1
B2
O1-
O1+
O2+ O2-
Feed-
back
Y10 Y11 Y12 Y13
Inputs
fast
O3 O4
O5
S35
Y1 Y2
Feed-
back
T0
T1
Inputs
fast
S36
Input
slow
Input
slow
Supply
S11
Logic
=
Fig.: Block diagram
Potential isolation, potential connection:
}
Potential isolation between the supply voltages A1/A2 and B1/B2.
}
Potential connection between the power outputs O1+/O1, O2+/O2 and the supply
voltage B1/B2.
}
Potential connection between the semiconductor inputs and singlepole outputs,
voltage output and supply voltage A1/A2.
4.2
Functions
4.2.1
Switching the power circuits on and off (fast shutdown)
The device has two safe dualpole outputs O1+/O1 (power circuit 1) and O2+/O2(power
circuit 2), which can be switched using inputs Y10/Y11 (power circuit 1) and Y20/Y21
(power circuit 2):