Essentials of OMRON CQM1H PLC System

Typical applications: Multi axis position detection, encoder high-speed counting, fixed length cutting control.

2. Pulse I/O board (CQM1H-PLB21)

Applicable slot: Right slot only

Pulse input: 2 channels, single-phase up to 50kHz, differential phase 25kHz. Support target value/region comparison interruption.

Pulse output: 2 channels, up to 50kHz (20kHz when connected to a stepper motor). Supports trapezoidal acceleration and deceleration control with fixed duty cycle (50%) (using PULS/PED commands) and variable duty cycle (1% -99%, using PWM commands).

Typical applications: stepper motor positioning control, proportional solenoid valve drive, frequency adjustable PWM heating control.

3. Absolute Encoder Interface Board (CQM1H-ABB21)

Applicable slot: Right slot only

Core function: 2-channel absolute encoder input (binary Gray code, maximum counting frequency 4kHz), resolution 8/10/12 bits optional. Support origin compensation (set to zero at any position) and power-off to maintain position data.

Interruption: Target value comparison (48 points) or region comparison (8 intervals).

Typical applications: Absolute position detection of rotating workbenches, height positioning of lifting equipment.

4. Simulation setting board (CQM1H-AVB41)

Applicable slot: left or right slot (but not both at the same time)

Core function: 4 multi turn potentiometers, with set values stored in IR 220 to IR 223 using 4-digit BCD codes (0000-0200).

Typical application: Operators manually adjust timer settings, speed settings, and PID target values without the need for programming equipment.

5. Analog I/O board (CQM1H-MAB42)

Applicable slot: Right slot only

Input: 4-channel, can independently select -10~+10V, 0~10V, 0~5V or 0-20mA, resolution 1/4096, A/D conversion time 1.7ms/point.

Output: 2 channels, can independently select -10~+10V or 0-20mA, D/A conversion time is 1.7ms/2 points.

Accuracy: ± 0.5% FS at 25 ° C, ± 1.0% FS at 0-55 ° C.

Note: There is no hardware averaging function, and if filtering is required, the AVG instruction in the program must be used.

Typical applications: analog sensor acquisition, frequency converter speed setting, servo torque command.

6. Serial Communication Board (CQM1H-SCB41)

Applicable slot: only left slot

Port: 1 RS-232C (maximum 19.2kbps, 15m), 1 RS-422A/485 (maximum 19.2kbps, 500m, supports 1: N connection).

Protocol support: Host Link, no protocol, protocol macro, 1:1 data link, NT link (1:1 or 1: N).

Protocol macros: Allow users to create custom communication protocols using CX Protocol software, exchange data with serial devices such as thermostats, barcode scanners, and smart meters, and execute them in single steps through PMCR instructions.

Typical applications: Communicating with multiple frequency converters, connecting touch screens (NT Link), and reading third-party instrument data.

I/O unit and communication unit: the cornerstone of building a complete control system

1. I/O unit

Input unit: DC input (12V/24V, 8/16/32 points), AC input (100-120V or 200-240V, 8 points). The response time can be set to 1-128ms in the PLC setup.

Output unit: Relay output (2A/point, 8/16 points), transistor output (NPN or PNP, 0.1A-2A), three terminal bidirectional thyristor output (0.4A).

Specialized I/O units: B7A interface unit (single cable up to 500m), temperature control unit (thermocouple/platinum resistor, 2/4 circuits, with heater disconnection alarm), safety relay unit (2 safety inputs+4 general inputs), analog input/output unit (CQM1-AD042/DA022), etc.

2. Communication unit

Controller Link Unit (CQM1H-CLK21): Supports data linking (automatic data sharing, maximum 1000 word transmission/8000 word reception per node) and information services (SEND/RECV/CMND instructions). Transmission distance: 500m at 2Mbps, 800m at 1Mbps, 1km at 500kbps. Up to 32 nodes. Suitable for multi PLC data exchange in production lines.

DeviceNet I/O Link Unit (CQM1-DRT21): DeviceNet slave station, 16 inputs/16 outputs, occupying 1 input word+1 output word. Supports 125/250/500kbps, with a maximum communication distance of 500m (125kbps).

PROFIBUS-DP I/O Link Unit (CQM1-PRT21): Slave, configurable 2/4/6/8 word I/O, automatically detects 9.6k-12Mbps baud rates, addresses 0-99. Support DP functions such as Sync/Freeze/Clear.

CompoBus/S Master Station Unit (CQM1-SRM21-V1): Supports high-speed mode (750kbps, 100m) and long-distance mode (93.75kbps, 500m). The number of I/O points can be set to 128 points (64 in/64 out), 64 points, or 32 points, with 4 or 8 points per slave station. The fastest communication cycle is 0.5ms.

AS Interface Master Station Unit (CQM1-ARM21): controls up to 31 slave stations, with 4 inputs and 4 outputs per slave station, and a communication cycle of 5ms.

Advanced features: interrupts, high-speed counting, and pulse output

CQM1H provides multiple interrupt handling mechanisms, significantly improving real-time response capabilities:

1. Input interrupt

The four points of IR 00000~IR 00003 built into the CPU unit can be used as interrupt inputs. After being enabled by the INT (89) instruction, when the input signal changes from OFF to ON, the main program pauses and immediately executes the corresponding interrupt subroutine (subroutine number 00-03). The interrupt response time is not affected by the PLC scanning cycle and is suitable for emergency parking, high-speed detection, and other scenarios.