MNET-8A8R is a communication slave product whose digital I/O, analog I/O, temperature sensor inputs, and high-speed pulse I/O can be controlled from a master device such as a PC, HMI, or PLC using Modbus or LS Industrial Systems Cnet.

Consists of a CPU module (1 RS-232 channel, 1 RS-485 channel, and 1 UART channel) and an I/O module (8 digital inputs and 8 relay outputs).

Select Modbus RTU Slave or LS Industrial Systems Cnet Slave in the options when ordering.

Check the CPU module communication terminals and internal power terminals.

Communication interface	Product terminal labels	Device connection example
RS-232	TX, RX, GND
RS-485	485+, 485−
UART	TXD, RXD, GND
I²C / internal power	SDA, SCL / +5V, GND

Cross the transmit and receive terminals for RS-232 and UART; match polarities for RS-485. For UART, verify that the signal voltage is compatible with the other device.

See the one-channel digital-input check before wiring for the first time. →

Input group	Communication address	Input configuration	Terminal blocks and wiring examples
0~3	Modbus 0~3 Cnet P0000~P0003	4 isolated inputs 4 points / 1COM
4~7	Modbus 4~7 Cnet P0004~P0007	4 isolated inputs 4 points / 1COM

Each group of 4 inputs shares one COM terminal, and both groups support PNP or NPN wiring. For PNP, connect COM to supply −; for NPN, connect COM to supply +.

The DC 24V shown in the diagram is a wiring example. The operating input voltage is DC 0~80V, and HIGH detection requires DC 5V or higher.

See the one-channel relay-output check before wiring for the first time. →

Output group	Communication address	Output configuration	Terminal blocks and wiring examples
0~3	Modbus 32~35 Cnet P0032~P0035	4 dry contacts 4 points / 1COM
4~7	Modbus 36~39 Cnet P0036~P0039	4 dry contacts 4 points / 1COM

Relay outputs share one COM terminal for every 4 points. The output contact rating is DC 0~30V or AC 0~250V, with a maximum allowable current of 5A/1 point and 8A/1COM.

The baud-rate DIP switch has 3 bits; switches 1·2·3 have values 4·2·1 respectively. The leftmost switch is the most significant bit.

Set value	Baud rate	Switch 1	Switch 2	Switch 3	Switch appearance
0	9,600bps	OFF	OFF	OFF
1	14,400bps	OFF	OFF	ON
2	19,200bps	OFF	ON	OFF
3	28,800bps	OFF	ON	ON
4	38,400bps	ON	OFF	OFF
5	57,600bps	ON	OFF	ON
6	76,800bps	ON	ON	OFF
7	115,200bps	ON	ON	ON

The slave-address DIP switch has 4 bits; switches 1·2·3·4 have values 8·4·2·1 respectively. Form the desired address by adding the values of the selected switches.

Setting example	Switch 1 (8)	Switch 2 (4)	Switch 3 (2)	Switch 4 (1)	Switch appearance
Address 0	OFF	OFF	OFF	OFF
Address 1	OFF	OFF	OFF	ON
Address 5	OFF	ON	OFF	ON
Address 10	ON	OFF	ON	OFF
Address 15	ON	ON	ON	ON

Set the DIP switches with power off. The master device's baud rate, data bits, parity, and stop bits must match the communication settings of the delivered product.

The X module offers selectable DC 0~5V, DC 0~10V, 0(4)~20mA, or NTC inputs. Connect a 2-wire or 3-wire PT100Ω sensor to the F module. The Y module offers selectable DC 0~5V, DC 0~10V, or 0(4)~20mA outputs.

Available option combinations depend on the product. Products with optional modules are assembled in the selected configuration, so exchanges or refunds after purchase may be difficult.

Configure analog inputs (X) and PT100Ω inputs (F) for a combined maximum of 20 points, and analog outputs (Y) and high-speed pulse outputs (K) for a combined maximum of 12 points. You cannot order a configuration that simply adds the maximum point count of every module.

Options are assembled and shipped in the selected configuration; users cannot add or remove I/O or optional modules. Also see MNET Series option configuration guide.

• X analog input values range from 0~32,767. Interpret them according to the selected input mode.
• X in NTC mode and F PT100Ω inputs transmit temperature multiplied by 10. For example, a received value of 213 means 21.3℃.
• Y output settings range from 0~65,535. Use them according to the selected output mode.
• K has a fixed WIDTH of 65,535 and outputs pulses from a Duty setting of 0~65,535. Contact us when ordering if you need to change the frequency or output pulse count.

Use the address ranges below that correspond to the installed optional modules. The slave-address DIP switch selects the station address of the product to communicate with; the addresses in this table select items to read or write within that product.

The confirmed separate addresses for the X module in NTC mode are as follows.

The Cnet addresses for NTC are D2080~D2087. Enter these addresses using their own notation, distinguishing it from other option addresses.

1. Verify that the ordered product's communication protocol matches the master device.
2. Turn off power and wire the required RS-232, RS-485, or UART port.
3. Set the baud-rate and slave-address DIP switches.
4. Match the master device port, baud rate, data bits, parity, stop bits, and target slave address to the delivered product settings.
5. Check wiring and settings, then turn on the power.
6. Read the first input to check communication. The Modbus RTU internal address is 0 and the LS Industrial Systems Cnet address is P0000.
7. Verify that the load is safe for an output test, then control the first output. The Modbus RTU internal address is 32 and the LS Industrial Systems Cnet address is P0032.
8. After verification, apply all required addresses in order.

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