Omron CV500 Installation Manual page 70

Power Supply Units
3-4-4 Emergency Stop
3-4-5 Power Interruptions
Power supply
Power interrup-
tion detection
signal
Program execution
Momentary Power
Interruption Flag
(A40202)
CPU reset signal
RUN output
You can use an external relay (CR in the following figure) to form an emergency
stop circuit that shuts down the system when PC operation stops. This can be
achieved by wiring the RUN output from the Power Supply Unit on the CPU Rack
as shown below.
MCB1
MCB2
A sequence circuit is built into the PC to handle power interruptions. This circuit
prevents malfunctions due to momentary power loss or voltage drops. A timing
diagram for the operation of this circuit is shown below.
Power interruption
85%
power interruption detection time: 10 to 25 ms*
Shutdown processing
Normal
Stops
Standby
*0.3 to 1 ms for DC power.
Power supply
CR1
Control section
Transformer
or noise filter
Twisted-pair wires
DC voltage
regulator
PC RUN
output
CR1 Surge suppressor
Momentary power inter-
ruption time (default: 0 ms)
Power OFF
interrupt program
Power retention time: 10 ms (fixed)
Section 3-4
PC
+
DC
input/output
–
Initialization
Normal
Power-ON
interrupt program
57