Technical FAQs

Ask a Question

What are the points to check in case of SLF1 fault on Altivar71/61 drive?

Issue:
Basic troubleshooting a SLF1 fault on Altivar71/61 drive.

Product Line:
All ATV61 ATV71

Environment:
All

Cause:
Fault condition drive will not run

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

On configuration:
- Check the master 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.


 
Was this helpful?
What can we do to improve the information ?