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).

Timeout monitoring: Timeout times (939, 941, 942, 945, in milliseconds) can be set for SYNC and each RxPDO separately. If timeout occurs, faults F2200~F2203 will be reported.

Virtual Links and Data Mapping

EM-IO-04 maps internal variables (such as control words, status words, and actual frequencies) to 8 bytes of PDO through a "virtual link" mechanism. Each byte of TxPDO can be configured as a boolean, word, or long integer.

1. Selection of TxPDO data source

The input parameters corresponding to each byte are 946-977 (for example, Byte1-4 of TxPDO1 corresponds to Boolean1-4, Byte5-8 corresponds to Word1-4, or Long1-2).

Enter the 'source number' during setup. Common sources: control word 740, status word 741, output frequency reference value 62, output percentage 138, digital input status 250.

Unused bytes are set to source 9 (zero value) or 7 (False).

2. RxPDO data target

The received data is mapped to source numbers 700~729 (such as 704 for Boolean1709 for Word1, etc.), and then these sources can be referenced internally through parameters in the frequency converter (for example, setting control word input parameter 99 as source 704).

Engineering example: Two frequency converters need to start and stop synchronously. The host places the control word (740) into Byte1 of TxPDO1; After receiving RxPDO1, link Byte1's source 704 to its own control word input parameter 99. In this way, the slave can follow the start stop instructions of the host.

Digital input/output configuration

1. Digital port EM-S1IOD

Select input (0) or output (1) through 558 (Operation Mode).

When in input mode, the signal source can be selected in 558 (320=direct input, 520=inverse), and the signal can be mapped to logic such as fixed frequency switching (parameter 131 defines the third bit fixed frequency switching).

When in output mode, select the output function (such as operating status, faults, etc.) through 559. Please refer to the frequency converter operation manual for specific functions.

2. Digital inputs EM-S2IND and EM-S3IND

High trigger (PNP) or low trigger (NPN) can be selected through the operation mode, corresponding to parameter values of 0 or 1 (see section 5.2.1).

When referencing these inputs in the parameters, use operation mode 321 (S2IND) or 322 (S3IND), or take the reverse version 521/522.

3. Fixed frequency switching extension

EM-IO-04 has expanded the third fixed frequency switching (131), which, when combined with the original two bit switching (66, 67), can achieve 8 fixed frequencies (480~488).

4. Status monitoring

All digital signal statuses can be viewed through parameters 250 (Digital inputs) and 254 (Digital outputs). Binary bits 7, 8, and 9 correspond to EM-S1IND, EM-S2IND, and EM-S3IND, respectively; Bit 3 corresponds to the state when EM-S1IOD is used as the output.

Motor temperature protection configuration

EM-IO-04 supports two types of temperature sensors: PTC thermistor (or bimetallic switch) and KTY84-130 temperature sensor, which can be switched by dialing S3.

1. PTC/bimetallic mode (S3 to the right)

Connect PTC (response threshold>2.4 k Ω) or normally closed bimetallic switch.

570 (Operation Mode Motor Temp.) can be selected from:

11: Warning only;

12: Fault shutdown (immediate);

13-15: Fault shutdown delay of 1/5/10 minutes.

Fault F0400 reported during overheating.

2. KTY temperature measurement mode (S3 to the left)

Connect the KTY84-130 sensor (resistance range 424 Ω~1722 Ω corresponding to -20 ℃~200 ℃).

Parameter 465 needs to be set to 22 (temperature measurement).

The maximum allowable winding temperature can be set to 617 (max. Temp. Windings), and in case of overheating, a warning or fault shutdown (F0400) will be generated according to the setting of 570.

The actual temperature can be read in real-time through parameter 226 (Winding Temperature).

The KTY mode also allows the frequency converter to automatically adjust control parameters (such as magnetic field orientation control) based on actual temperature, optimizing motor performance.

Note: Regardless of the type of sensor used, temperature evaluation is independent of digital input enable signals and will continue to monitor even in a shutdown state.

System bus fault diagnosis and troubleshooting

The fault codes caused by EM-IO-04 are as follows:

Fault code description, troubleshooting suggestions

F0400 motor temperature is too high or the sensor connection is faulty. Check X410B. 1-2 wiring, confirm that the sensor type matches the S3 dip code, and check whether the PTC resistance or KTY is short circuited/open circuited

F1450 KTY temperature measurement fault check if S3 is on the left position, check if the sensor resistance is within the effective range, and check the wiring terminals

F21nn system bus slave fault (nn=node ID) Check if the corresponding slave loses power or if the bus is short circuited, and check the terminal resistance configuration

F2200 SYNC timeout: Confirm whether the master station sends SYNC, check 919 settings, and check bus load

F2201~F2203 RxPDO1-3 timeout check whether the corresponding TxPDO is sent normally and whether the identifier matches

F2210 CAN bus BUS OFF Check if the bus line is short circuited/open circuited, if the baud rate is consistent, and if the terminal resistance is correct

Debugging skills:

By using VPlus software (in conjunction with KP232), real-time monitoring of node status (978) and CAN physical layer status (979, OKAY/WARNING/BUS-OFF) can be achieved.

If the bus load is too high (>70%), the PDO transmission frequency should be reduced or the baud rate should be increased to avoid message conflicts.