Bonfiglioli EM-IO-04 Expansion Module Configuration Guide

Bonfiglioli EM-IO-04 Expansion Module Engineering Configuration and Troubleshooting Complete Guide

In industrial variable frequency drive systems, flexible digital expansion, motor temperature monitoring, and system bus communication capabilities are often the key factors determining project success or failure. Bonfiglioli provides EM-IO-04 expansion modules for ACT and ACU series inverters, integrating programmable digital ports, dual digital inputs, PTC/KTY temperature sensing interfaces, and CAN system bus, providing engineers with a one-stop I/O and communication expansion solution. This article is based on the official technical manual, and systematically elaborates on the engineering application points of this module from the dimensions of hardware installation, system bus configuration, process data mapping, digital quantity configuration, and motor temperature protection, to help on-site engineers quickly complete deployment and fault diagnosis.

Overview of module functions and applicable scenarios

The EM-IO-04 expansion module is installed in the lower expansion slot of the frequency converter, and its main functions include:

CAN system bus: compliant with ISO-DIS 11898 (CAN High Speed), up to 1 Mbaud, optically isolated, supporting CANopen protocol framework;

Digital port EM-S1IOD: can be software configured as input or output (PNP/NPN optional);

Two digital inputs EM-S2IND and EM-S3IND: supports triggering at HIGH or LOW levels (PNP/NPN adjustable);

Motor temperature monitoring: Select PTC thermistor (or bimetallic switch) or KTY84-130 temperature sensor through dip switch S3 to achieve temperature limit alarm or continuous temperature measurement and control optimization;

Two 20V auxiliary power outputs (total current of 180 mA).

This module is suitable for applications that require the addition of digital control points, remote start stop signals, motor overheating protection, and multi machine CAN bus networking, such as pump stations, transmission lines, lifting equipment, and wind power pitch systems.

Mechanical installation and electrical wiring specifications

1. Mechanical installation steps

The frequency converter must be completely powered off and wait for the DC bus capacitor to discharge (at least 5 minutes).

Remove the lower cover plate of the frequency converter to expose the expansion slot.

Insert the EM-IO-04 module vertically into the slot, ensuring that the pins are fully engaged.

Reinstall the cover plate, and the module will automatically recognize after power on.

2. Definition of wiring terminals

The module provides two pluggable terminal blocks X410A and X410B:

X410A: Terminals 1, 4, and 7 are 20V auxiliary power output (shared total current of 180mA); Terminal 3 is the EM-S2IND digital input; Terminal 6 is the EM-S3IND digital input; Terminals 2 and 5 correspond to each other.

X410B: Connect terminals 1-2 to the motor temperature sensor (PTC or KTY); Terminal 3 is a digital port EM-S1IOD (configurable as input or output); Terminal 4 is 20V ground; Terminals 5, 6, and 7 are CAN_L, CAN_S, and CAN_SND, respectively.

Safety precautions:

All control signal lines must be laid separately from power cables, using shielded twisted pair cables, and both ends of the shielding layer must be grounded extensively.

Before wiring or disconnecting, the power supply of the frequency converter must be cut off to prevent damage to the module or endangering personal safety.

System bus (CAN) configuration and communication parameters

The CAN interface of EM-IO-04 supports multi node networks (up to 63 slave stations plus 1 master station) and adopts a linear topology. All nodes must be set to the same baud rate and correctly configured with terminal resistors.

1. Node ID and baud rate

900 (Node ID): Value range 1~63, set to 0 to indicate that the local machine is the master station, set to -1 to shut down the bus (factory default).

903 (Baud Rate): Available in 50, 100, 125, 250, 500, and 1000 kBaud, with corresponding maximum bus lengths of 1000, 800, 500, 250, 100, and 10 meters. The selection should be based on the actual cable length.

2. Terminal resistor configuration

There are dip switches S1 and S2 on the module:

Passive terminal: S1=ON, S2=OFF (regular).

Active terminal: S1=ON, S2=ON (improves long line signal edge).

Note: Only the physical head and tail nodes enable the terminal, and the intermediate nodes must be turned off (S1=OFF, S2=OFF).

3. Functions of master and slave stations

If the local machine is the master station (Node-ID=0), it is necessary to manage network startup (send Start Remote Node command) and SYNC message.

904 (Boot Up Delay): The delay time for the master station to wait for the slave station to initialize, with a default of 3500 ms.

919 (SYNC Time): SYNC message sending cycle (ms), set to 0 to not send synchronization.

918 (SYNC Identifier): SYNC message identifier, default 128 (following predefined connection set).

4. SDO and PDO channels

SDO1 is used for parameter reading and writing (identifiers can be modified through 921/922), and SDO2 reserves visualization tools (can be closed through 923).

PDO channels (3 sets of Rx/Tx) are used for real-time process data exchange, with identifiers set through 924~929, and default to follow predefined connection sets (such as TxPDO1=384+Node-ID).