42 M OT O R CO N T R O L A N D P R O TE C T I O N U N I T M 1 0X U S E R G U I D E
The maximum thermal capacity level is 100%.
Maximum level is reached when the motor has
been running with a current 6xIn at the time t6
starting from the cold state in ambient
temperature 40°C.
Trip class
10A 3-7
10 7-12
20 10-25
30 15-38
—
If motor is in overload condition, i.e. ILmax > 1.14
x TFLC (thermal full load current multiplier
reduced by motor ambient temperature), the
overload alarm is activated to indicate overload.
In some applications, it is beneficial to be able to
bypass the TOL protection momentarily because
of the process reasons. The lifetime of the motor
will be shortened, but it might the more costly to
stop the process.
TOL bypass function is designed for this reason.
If a TOL bypass is activated,
• when the motoring is running, the thermal
capacity is allowed to rise to 200% before a trip
occurs;
• when the motor is already taken off line due to
TOL, the motor is ready for an emergency start
as long as the thermal level is below 200%.
More details refer to 'TOL bypass' function under
digital input functions section.