Basic Tcp Modbus Diagnostic Information - ABB PSE Manual

6 Basic TCP Modbus Diagnostic Information

PSE trips on fieldbus fault (EF40)

The purpose of the fieldbus fault function is to detect any communication problems between the Modbus
master and the Softstarter. Fieldbus fault will be enabled if the Fieldbus control parameter is set to On and
Operation when fault parameter is set to trIP.

When fieldbus fault reaction is set to trip, the Softstarter will trip on Fieldbus Fault (EF40) after a set time of
no communication. The timeout parameter value is set to 10 s and cannot be changed.

If there has been a trip on fieldbus fault for some reason, the communication has to afterwards be
continuously stable for 10 s before the Softstarter accepts commands from the Modbus master and when it is
possible to reset the fault.

If the Reset of Fieldbus Fault PSE parameter is set to Auto and the fieldbus fault (EF40) has tripped due to
no communication, 30 s of stable communication is required before an automatic reset is performed.
Motor does not start

If fieldbus fault reaction is set to "switch to local" control and fieldbus communication is lost and/or timeout
is reached, the Softstarter can only be controlled with hard-wire signals. When communication is re-
established, there is a 10 second delay before fieldbus control is possible.

Check if the fieldbus control parameter is set to ON.

Make sure the auto mode is enabled in order to control the motor with Modbus. The data value in respective
protocol address for the connected PSE devices shall be set.

Check if the stop coil is set since it has higher priority than the start coil.

Motor will not start if there is an active fault (check the ready to start coil).
ABB AB
Control Products
SE-721 61 Västerås, Sweden
www.new.abb.com/low-voltage/products/softstarters
www.abb.com/drives
1SFC132374M0201 21