Connect igus encoders with Beckhoff and B&R

There are control systems whose encoder card is usually compatible with 24V and/or single-ended encoders. igus motors, however, work with 5V and as line drivers. Connecting these two voltages requires another component or a special encoder card. In this article, we look at the connection of igus motors to control systems that work with 24V and/or single-ended encoders, such as the manufacturers Beckhoff and B&R*

*Beckhoff and B&R are registered trademarks of Beckhoff GmbH & Co. KG and B&R GmbH.

Encoders from igus

The standard encoders we use at igus operate with a supply voltage of 5V. The line driver version has differential signal transmission, making it particularly insensitive to electromagnetic interference. The signals from the encoder are output with a signal level of 5V. An encoder card with a signal level of 24V will detect a 5V signal as a low or undefined signal and therefore will not evaluate it.

Single-ended encoders do not have a complementary signal, such as the A, B and N signals. Unfortunately, it is not possible to simply ignore the complementary signal as it represents the active counter-potential to the A, B and I signals and therefore essential for correct signal processing. A converter is required to solve this problem (see Solution 2).

How we solve the problem

Depending on the control system, there are different approaches to solving the problem:

Solution 1 - Using an RS422 card

Most manufacturers offer a suitable encoder card that you can take into account when planning the PLC.

Solution 2 - Signal conversion

If your PLC already exists (and does not have an RS422 card/input), you can convert the line driver protocol of our encoder into a single-ended encoder signal. We offer the matching converter with the part number DRI-CON-5. It is important that the voltage supply of 5V +- 0.2V must nevertheless be provided from your side.

Solution 3 – igus dryve D1

You can also simply use our motor control system and connect it to your PLC via CANopen or Modbus TCP Gateway. You can find the suitable sample programs here.

Solution 4 - Use your own motor

If all these solutions do not suit you, you can of course, use your own motors. For our linear axes and rotary axes we can offer a suitable motor flange here.