Chapter 5 – Fault Tracing
5-4
ACS 501 Installation & Start-up Manual
Fault Messages
= press once to reset fault.
= remove power to reset fault.
Fault Message
Possible Cause
Remedy
1 START/STOP
The start/stop reference from
Control Interface Card is
different from the start/stop
state of the Motor Control
Card.
• Check the connection
between Control Interface
and Motor Control Cards.
• If the fault persists, contact
ABB Technical Support.
2 OVER TEMP
The heat sink temperature is
greater than 158
°
F (70
°
C).
Restricted air flow caused by
dust or improper installation.
Refer to Figure 5-2 at the end
of this chapter.
3 MOT STALL
The ACS 501 has determined
that the motor is operating in
the stall region. Refer to
Parameter 30.1.10 (Stall Time/
Freq). The motor is not turning
because of increased load
torque. Motor may be too small
for the application.
• Remove the mechanical
problem causing increased
load torque.
• If the motor shaft is rotating
and the motor is not
overheating, increase stall
limit parameters.
• Check drive sizing, use larger
ACS 501 and motor if
necessary.
4 MOTOR TEMP
The ACS 501 determined that
the motor is overheated.
Because the temperature rise is
calculated from the motor
current and not measured
directly, the motor may be
within temperature rise
specification, especially with
long motor cables where
capacitive currents will
increase the current from the
drive.
• Check the motor temperature.
If it is within temperature rise
specification, increase
Parameter 30.1.5 (Motor
Load Curve) and/or
Parameter 30.1.4 (Motor
Therm Time) and restart.
• If the motor temperature is
above rated temperature,
improve motor cooling or
resize the motor.
7 UNDER LOAD
The motor load has dropped
below the Supervision Limit set
by Parameters 30.1.12 and
30.1.13.
• Fix mechanical problem
causing underload.
• Check motor load cycle and
increase Parameter 30.1.12
(Underload Time) or
Parameter 30.1.13
(Underload Curve).
