Omron C1000H/C2000H PLC Practical Guide

Note: The PS222-E power supply for the expansion rack can provide 6.5A, which is more abundant than the power supply for the CPU rack.

I/O wiring specifications

5.1 Terminals and crimping terminals

Use ring clamp terminals and do not directly connect bare wires.

Terminal screw torque: 0.8 N · m.

The terminal block is detachable: simply loosen the upper and lower fixing screws to pull it out without disconnecting the wires.

5.2 DC Input Wiring

Pay attention to polarity. For DC input units, the COM termination method determines the Sink or Source input.

Two wire sensors (photoelectric switches, proximity switches) have leakage current. If the leakage current is greater than 1.3mA, a discharge resistor should be connected in parallel at the input end. Calculation formula:

Maximum resistance value R [k Ω]=7.2/(2.4 × I2 leak (mA) -3)

Minimum power W=2.3/R

5.3 Output wiring protection

Relay output:

Capacity: 2A at 250V AC or 2A at 24V DC (resistive load)

Inductive load (contactor, solenoid valve) lifespan: 100000 operations (AC 240V cos φ=0.4)

Surge absorbers (AC: RC absorbers) must be connected in parallel; DC: freewheeling diode)

Suggest adding 5-10A fuses every 4 output points

Transistor output:

Voltage: 12~48V DC, current specifications vary by model

Leakage current ≤ 0.1mA, residual voltage 1.4~1.5V

When driving TTL circuits, a pull-up resistor needs to be added

When driving surge loads such as incandescent lamps, the surge current can reach 10 times the rated current, and a current limiting circuit needs to be added

Bidirectional thyristor output:

Leakage current of 3~6mA may cause low current loads to not be completely turned off, and parallel discharge resistors are required

Built in non replaceable fuse (5A 250V)

5.4 Special precautions for AC input

The ON response time of the AC input unit is about 35ms, and the OFF response time is about 55ms, which is not suitable for high-speed counting or interruption.

If a reed switch is used as the input contact, its rated current must be ≥ 1A, otherwise surge may cause welding.

Key operating points of Duplex dual machine system

6.1 Initial Settings

Install identical memory packages (with the same capacity and write protection switch) in two CPUs.

Turn the system switch on the Duplex unit to the DPL position.

Turn the active CPU selection switch to RIGHT or LEFT.

Set the ON/OFF switches of both CPUs to the ON position.

After power on, the active CPU starts running and the standby CPU enters a hot standby state.

6.2 Fault Switching

If a fatal error occurs in the active CPU, the system automatically switches to Simplex mode, and the standby CPU becomes the active CPU and takes over control. At this point, the switch status on the Duplex unit no longer reflects the actual active CPU.

If the standby CPU fails, the system will automatically downgrade to Simplex mode, and the active CPU will continue to run.

The faulty CPU can be replaced during system operation (without power outage), but the program needs to be resynchronized after replacement.

6.3 Temporary switch to Simplex mode

When only one CPU is needed for program debugging or writing, the Duplex system can be switched to Simplex mode. Operating procedures:

Place the system in Program mode through the programmer.

Set the ON/OFF switch of the unused CPU to OFF.

The system will run on a single CPU.

Maintenance and troubleshooting

7.1 Regular inspection items

Project standard cycle

Power supply voltage AC: 85-132/170-264V; DC: 20.4-28.8V for six months

Environmental temperature 0-55 ℃ for half a year

Terminal screw torque 0.8 N · m for half a year

Expansion cable lock buckle tightened without looseness for six months

The battery voltage ALARM light does not light up every month

7.2 Fuse replacement

Power fuse (located on the circular knob on the side of the power unit):

Use a Phillips screwdriver to rotate counterclockwise by about 50 ° and remove the fuse holder.

Replacement specification: PS221/222/223 uses 3A 250V (6.35 × 32mm); PS211/212 uses 4A 125V; PS213 uses 6.3A 250V.

Rotate clockwise.

Output unit fuses (such as OD411, OA121, etc.):

After power failure, remove the output unit, open the casing, find the fuse (usually a 5 × 20mm glass tube) on the circuit board, replace it, and assemble it.

7.3 Battery Replacement

The CPU and some memory packs use lithium batteries (3G2A9-BAT08) with a lifespan of approximately 4 years (25 ℃). When the programmer displays "BATT LOW", it must be replaced within one week.

Steps (to be completed within 5 minutes):

Power off (if power has already been cut off, power on for at least 1 minute before turning off).

Open the battery compartment cover (on the right or below the CPU front panel).

Unplug the old battery connector and immediately insert the new battery.

Cover the compartment lid.

After powering on again, if there are still error messages, press the programmer CLR → FUN → MONTR to clear them.

7.4 Common Fault Diagnosis

Possible causes and solutions for the phenomenon

The POWER light is not on and there is no input power supply; Internal fuse breakage measurement power terminal voltage; Replace the fuse

RUN light not on, program error; No END instruction; The mode switch is in the Program check program; Switch to RUN mode