Issue:
SLF1 fault causes on Altivar71/61 drive

Product Line:
All ATV61 ATV71


Resolution:
A modbus communication fault indicates that the communication has worked properly between the drive and the server.  But during the time set in [Modbus time out] (ttO) parameter, a loss of communication has been detected.

On configuration:
- Check the server state (RUN, stop…).
- Check if there is no network overload.
- Check the time out value (try to increase the value).
- Check the time between the sending of 2 Modbus requests (if the time is higher than the time out value, the drive can trip in fault).

On environment:
- Use the Telemecanique cable with 2 pairs of shielded twisted conductors (catalog number: TSXCSA100, TSXCSA200 or TSXCSA500).
- Keep the Modbus cable away from the power cables (30 cm minimum).
- If it is necessary for the Modbus cable and the power cables to cross each other, be sure they cross at right angles.
- A reflection in a transmission line is the result of an impedance discontinuity that a traveling wave sees as it propagates down the line. To minimize the reflections from the end of the RS485-cable, it is required to place a line termination near each of the 2 ends of the bus.
- Whenever possible, connect the cable shielding to the protective ground, e.g., to the ground of each device if this ground is connected to the protective ground.

If this article does not answer your question, check out our FAQ database that has answers to more commonly asked questions:
Frequently Asked Questions - Schneider Electric (se.com)

If this FAQ did not solve your issue, you can call us at 1-888-778-2733 Option 2 and then 4 or e-mail us at drive.products.support@se.com to create a case with our Technical Support Team.

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Released for:Schneider Electric Indonesia