IDEC FS1A Controller - Manual (Page 129)

5-88
Dual channel solid state input
This function is for connecting a safety device with a dual channel solid state output (PNP output),
such as a safety light curtain or a safety laser scanner. As shown in Fig. 5-7, this function is
comprised of a dual channel receive circuit (X
n
, X
n+1
) and a functional output (I
n
). The drive circuit
is not used because circuit monitoring is performed by connected safety devices.
Fig. 5-7 Circuit for dual channel solid state input function
Connects to
Safety devices with dual channel solid state outputs (PNP output), such as safety light curtains or
safety laser scanners.
Warning
Mechanical contact devices, such as emergency stop switches or interlock switch, cannot be
connected.
Note: Solid state output devices with sink outputs (NPN output) cannot be connected.
Description of operation
The operation timing is described in Fig. 5-8.
Ⅰ When the dual channel safety check signals from the safety device are correctly supplied to
the 2 input receiving circuits, the output is turned ON. (Ex. Safety light curtain is not
shaded.)
Ⅱ When the safety check signal to either of the receiving circuits is turned OFF, the output is
turned OFF immediately. (Ex. Safety light curtain is shaded.)
Ⅲ If safety check signals are not supplied correctly to the input receiving circuits, due to an
error in the safety device or input circuit, the output is turned OFF immediately. Status of the
detected error is displayed by the error LED, input LEDs and monitor output. (Ex. Fault in the
light curtain or wiring)
X
n
X
n+1
I
n
Input monitor error
detection time：Max.0.1s
①
② Independent conditon
change in one input
SafetyOne changes to
Protection after an input
monitor error is detected.
The monitor output
corresponding to the input
which occur error becomes
pulse output (1Hz).
0.5s 0.5s
Ⅰ Ⅱ Ⅲ Ⅱ Ⅰ Ⅱ
Y
m
(Monitor output)
Ⅱ
Cance-
llation
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Fig. 5-8 Operation timing of a dual channel solid state input function
X
n
X
n+1
Safety device
I
n
V+
V-
Dual Channel
Solid State