Bonfiglioli EM-ENC-02 Expansion Module Engineering Configuration Guide

Bonfiglioli EM-ENC-02 Expansion Module Engineering Configuration Guide

In industrial automation drive systems, frequency converters often require additional I/O, encoder feedback, or fieldbus communication capabilities to meet the needs of complex applications. Bonfiglioli provides the EM-ENC-02 expansion module for ACT and ACU series inverters, which integrates CAN system bus interface, bipolar analog input/output, incremental encoder input, programmable digital port, and motor PTC temperature measurement function. It is an ideal component for building distributed motion control networks. This article provides a detailed explanation of the key steps of hardware installation, system bus configuration, process data exchange, analog calibration, and encoder debugging for this module from an engineering practice perspective, helping on-site engineers quickly master its configuration skills.

Module overview and application scenarios

The EM-ENC-02 expansion module is installed in the lower expansion slot of the frequency converter, achieving "plug and play" through a unified interface. Its main functions include:

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

1 bipolar analog input (± 10 V or ± 20 mA, 12 bit resolution);

1 analog output (0-20 mA);

1-channel incremental encoder input (TTL/HTL, up to 300 kHz, supports direction recognition);

1 programmable digital port (input/output optional);

1-channel PTC thermistor or bimetallic temperature switch input.

This module is particularly suitable for situations that require multi machine synchronization (electronic gears), remote setpoint setting, actual speed feedback, and temperature monitoring, such as winding equipment, cranes, conveyor lines, and pump control.

Mechanical installation and safety precautions

1. 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 (exposing the expansion slot).

Align the EM-ENC-02 module with the slot and insert it vertically, ensuring that the pins are fully engaged.

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

2. Safety points

It is strictly prohibited to plug or unplug modules while they are live, otherwise it may damage the circuit.

The PCB on the back of the module is exposed to avoid touch and prevent electrostatic damage.

All control signal wiring (analog, encoder, CAN bus) must be laid separately from power cables, using shielded twisted pair cables and grounded at one or both ends (it is recommended to ground both ends extensively).

System bus (CAN) interface configuration

The CAN interface of EM-ENC-02 supports multi node networking (up to 63 slave stations plus 1 master station), using a linear topology. The following are the key configuration parameters.

1. Node ID and baud rate

Node ID: Set through parameter 900 (Node ID), with a value range of 1 to 63. If set to 0, the frequency converter serves as the system bus master station; Set to -1 to disable the bus function (factory default).

Baud rate: Select through parameter 903 (Baud Rate), with options of 50, 100, 125, 250, 500, and 1000 kBaud. The baud rate determines the maximum bus length (e.g. 25 m at 1000 kBaud and 1000 m at 50 kBaud). Ensure that all nodes are consistent.

2. Bus terminal resistance

There are two dip switches S1 and S2 on the module, which are used to activate the terminal resistor:

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

Active terminal: S1=ON, S2=ON (improves signal edge, suitable for long lines).

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

3. Main station function (when 900=0)

The main station is responsible for managing network startup (sending the Start Remote Node command) and generating SYNC synchronization messages (for synchronizing PDO).

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

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

SDO and PDO communication mechanism

The system bus is based on the CANopen protocol (DS 301), transmitting parameters through SDO (Service Data Object) and real-time control data through PDO (Process Data Object).

1. SDO channel

Each node has two SDO channels: SDO1 (for parameter reading and writing) and SDO2 (reserved visualization tool).

Identifiers are assigned according to predefined connection sets and can also be modified through parameters 921 (RxSDO1 ID) and 922 (TxSDO1 ID) (0 indicates using default values).

If SDO2 is not needed, it can be turned off through 923 (SDO2 Set Active).

2. PDO channel

Each node supports 3 sets of TxPDO (transmit) and 3 sets of RxPDO (receive), with a maximum of 8 bytes of data per set.

The identifiers are set by parameters 924 to 929 (RxPDO1/2/3, TxPDO1/2/3), and the default values conform to the predefined connection set (such as TxPDO1=384+Node-ID).

Transmission mode: Set the functional mode of each PDO through 930~938 (0=off, 1=time triggered, 2=SYNC triggered). The time triggered interval is set by 931/933/935 in milliseconds.

3. Timeout monitoring

Timeout times (parameters 939, 941, 942, 945, in milliseconds) can be set for SYNC and each RxPDO. If no data is received after the timeout, the frequency converter will report a fault (F2200~F2203).

Virtual links and data mapping

EM-ENC-02 maps internal variables to various bytes of PDO through a "virtual linking" mechanism. Each TxPDO's 8 bytes can be configured as boolean, word, or long integer data.

1. Selection of TxPDO data source

The input parameters corresponding to each byte are 946-977 (for example, bytes 1-4 of TxPDO1 correspond to Boolean1-4, bytes 5-8 correspond to Word1-4, or Long1-2).

Enter the 'source number' during setup. Example of commonly used source numbers:

Control word: 740

Status word: 741

Actual output frequency value (reference channel): 62

Output percentage actual value: 138

Digital input status (including expansion port): 250

If a certain byte is not used, set it to fixed source 9 (zero value) or 7 (False).

2. RxPDO data target

The received data will be mapped to the corresponding source numbers (700~729), and then these sources can be referenced internally through parameters in the frequency converter (for example, using 704 as the control word input, connected to parameter 99).

For example, sending the control word of another device through TxPDO, the local RxPDO receives it, and links the source 704 to its own control word input parameter 99 to achieve remote synchronous control.

Engineering example: Two frequency converters need to synchronize start stop and speed setting. Place the control word (740) and output frequency (62) of the host into bytes 1-2 and 5-8 of TxPDO1, respectively; After receiving from RxPDO1, bytes 1-2 are mapped to the control word input (parameter 99 is set as source 704), and bytes 5-8 are mapped to the frequency setting value input (parameter 137 is set as source 709). This way, the slave follows the host to run.

Analog input/output configuration

1. Analog input (EM-S1INA)

Hardware switching: Select voltage (OFF) or current (ON) mode by dialing code S3 on the module.

Characteristic curve: Define two linear points in percentages (corresponding to ± 10 V or ± 20 mA) using parameters 564~567 (X1, Y1, X2, Y2).

Operation mode 562:

1: Bipolar (full range mapping)

11: Unipolar (negative value returns to zero)

21: Monopolar 2~10 V/4~20 mA (for use with offset signal)

101: Bipolar takes absolute value (negative signal converted to positive)

Dead zone and hysteresis: 560 (tolerance band) can set the dead zone width near the zero position to prevent signal jitter from causing misoperation.

Fault response: 563 sets the behavior when the signal is below 1 V/2 mA (warning, deceleration shutdown, or immediate fault shutdown).

Filtering: 561 can choose a filtering time constant (0-5000 ms) to suppress noise.

Calibration: 568 can perform zero point calibration for 0 V and 10 V (or 0 mA and 20 mA) respectively.

2. Analog output (EM-S1OUTA)

The output is 0-20 mA current, and the output signal source (such as analog input absolute value, actual frequency, actual percentage, etc.) can be selected through 590 (Operation mode).

Offset and gain: 585 (Offset) and 586 (Amplification) can adjust output characteristics (such as mapping 0-100% to 4-20 mA for wire breakage detection).

Calibration: 599 is used to adjust the output zero point and full current, and is calibrated in conjunction with the operating modes of "0 mA" and "20 mA".

Encoder input interface configuration

EM-ENC-02 supports incremental encoders (TTL/HTL), which can be used as speed loops or position references.

1. Hardware connection

Wiring terminals X410A.1~4 correspond to A+, A -, B+, B - respectively.

If using a 5V differential signal (RS-422), the terminal resistor can be enabled (S4 switch ON); If using a 24V single ended signal, there is no need for a terminal (S4 OFF).

2. Parameter settings

493 (Operation mode speed sensor 2): Select 0=off, 4=fourth harmonic (bidirectional counting, direction recognition), 104=reverse fourth harmonic.

494 (Division Marks Speed Sensor 2): Set the number of pulses per revolution of the encoder (1~8192).

495 (Level): 0=push-pull (5V), 2=single ended (10-24V).

766 (Actual speed source): Select the actual speed source, 1=built-in encoder (basic unit), 2=encoder of this extension module.

3. Speed calculation

The maximum input frequency is 300 kHz, and based on this, the maximum speed can be calculated as follows: nmax=(300k × 60)/(number of pulses per revolution × 4) (fourth harmonic).

To maintain low-speed stability, it is recommended to have at least one pulse edge every 2 ms, with a minimum pulse frequency of 500 Hz, to calculate the minimum number of pulses required.

4. Application examples

When the encoder is used as speed feedback, set 766 to 2 and point the feedback source of the speed controller (such as PI) to this actual value.

If you need to use the encoder frequency as the frequency reference source, you can select operation mode 34 (absolute value of speed sensor 2) or 35 (speed sensor 2+MF11A) in the 475 (Reference frequency source).

Digital port and motor temperature protection

1. Digital port (EM-S1IOD)

Define ports as 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 fixed frequency switching).

When in output mode, select the output function (such as operating status, faults, etc.) through 559. The specific function list can be found in the frequency converter operation manual.

2. Motor temperature monitoring (EM-MPTC)

Connect PTC thermistor (compliant with DIN 44081, response threshold of approximately 2.6 k Ω) or bimetallic switch (normally closed) to X410B. 1-2.

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.

The simulated input EM-S1INA can also be used for temperature sensors (such as PT100), and mode 2 (temperature measurement) can be selected through 465. The actual temperature value can be viewed in parameter 253.

9、 Common fault diagnosis and troubleshooting

Fault code description, troubleshooting suggestions

F1402 Analog input signal fault (<1V/2mA) Check sensor wiring, confirm power supply and signal range, adjust 563 behavior

F30 encoder signal fault check A/B channel connection, confirm terminal resistance matching, check 494 pulse number setting

F31 encoder single channel missing measurement: Is there a differential signal between A+and A -, B+and B -

F32 encoder direction error: Swap A/B channels or set 493 to 104 (reverse)

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

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 being sent normally and whether the identifiers match

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

Debugging skills:

By using VPlus software (in conjunction with KP232 interface), real-time monitoring of bus messages, node status, and PDO data can be achieved.

For the new network, first set all node Node-IDs to -1 (turn off the bus), debug each frequency converter separately, and then gradually add them to the bus.