Omron CJ2 User Manual

A-115
Appendices
CJ2 CPU Unit Hardware User’s Manual
A-6 Load Short-circuit Protection and Line Disconnection Detection for Basic I/O Units
App
A-6-1 Load Short-circuit Protection and Line Disconnection Detection for CJ1W-OD202
A-6 Load Short-circuit Protection and
Line Disconnection Detection for
Basic I/O Units
This section describes the load short-circuit protection of the CJ1W-OD202 Output Units.
As shown below, normally when the output bit turns ON (OUT), the transistor will turn ON and then out-
put current (Iout) will flow.
Normal Operation
If the output (Iout) is overloaded or short-circuited exceeding the detection current (Ilim), the output cur-
rent (Iout) will be limited as shown in figure below. When the junction temperature (Tj) of the output tran-
sistor reaches the thermal shutdown temperature (Tstd), the output will turn OFF to protect the
transistor from being damaged, and the alarm output bit will turn ON to light the ERR indicator. When
the junction temperature (Tj) of the transistor drops down to the reset temperature (Tr), the ERR indica-
tor will be automatically reset and the output current will start flowing.
Operation for Overload or Short Circuit
If the line is disconnected and the output current (Iout) drops below the line disconnection detection cur-
rent (IOL), the ERR indicator will light as shown in the following figure.
Operation for Disconnected Line with Output Current below the Line Disconnection Detection Current
A: Load not connected or load line broken.
B: Current to load at or below line disconnection detection current.
C: Rise of current to load too slow and error detected before the disconnection detection current was
reached.
A-6-1 Load Short-circuit Protection and Line Disconnection Detection
for CJ1W-OD202
OUT
ON
OFF
I
OUT
ON
OFF
ERR
ON
OFF
OUT: OUTPUT instruction
I
OUT
: Output current
ERR: Alarm output, ERR indicator
I
lim
: Short-circuit detection current
I
OL
: Disconnection detection current
T
j
: Junction temperature of transistor
T
std
: Thermal shutdown temperature
T
r
: Reset temperature
OUT
ON
OFF
I
OUT
ON
OFF
ERR
ON
OFF
I
lim
Tj =Tstd Tj =Tr
OUT
ON
OFF
I
OUT
ON
OFF
ERR
ON
OFF
I
OL
ABC

Omron CJ2 Specifications

General

Model	CJ2
Manufacturer	Omron
Type	Programmable Logic Controller (PLC)
CPU Units	Multiple models available (e.g., CJ2M, CJ2H)
Number of I/O Points	Up to 2, 560 points
Communication Ports	Ethernet/IP, EtherCAT, USB, Serial
Expansion	Yes, via I/O Units and Special I/O Units
I/O Control Method	Cyclic Scan, Interrupt
Programming Language	Ladder diagram, structured text, function block diagram, sequential function chart, instruction list
Built-in I/O	Available on some models (e.g., CJ2M)
Ethernet Port	Yes, 1 port (depending on CPU Unit)
Serial Ports	RS-232C, RS-422/485 (configurable)
USB Port	Yes (for programming and monitoring)
Operating Temperature	0°C to 55°C
Storage Temperature	-25 to 70°C
Humidity	10 to 95% RH (non-condensing)
Vibration Resistance	10 to 57 Hz, Amplitude: 0.075 mm, 57 to 150 Hz, Acceleration: 1 G, X, Y, and Z directions, 80 min each
Power Supply Voltage	24 VDC or 100 to 240 VAC (depending on CPU Unit)