WEG SSW-07 User Manual - page 47
Chapter 6 - SOLUtION aND trOUBLeShOOtING
46
English
Protection
Description and
Fault Display
Activation Description
Probable Causes
Reset
Undervoltage
in the control
supply
E70
(LED Fault)
Flashes twice
(LED Ready)
Off
Activates when the control
supply voltage is lower than 93
Vac.
Electronics supply lower than the
minimum value.
Electronics power supply with loose
contact.
Electronics power supply fuse blown.
Power-on.
Reset key.
Auto-reset.
DIx.
Internal
By-pass relay
contact Open
E71
(LED Fault)
Flashes 3 times
(LED Ready)
Off
When there is a fault with the
internal By-pass relay contacts
at full voltage.
Loose contact in the starting cables
of the Internal By-pass relays.
Defective By-pass relay contacts due
to an overload
Power-on.
Reset key.
Auto-reset.
DIx.
Overcurrent
before the
By-pass
E72
(LED Fault)
Flashes 4 times
(LED Ready)
Off
Activates before the closing
of the By-pass if the current is
greater than:
37.5 A for the models up to 30 A;
200 A for the models from
45 to 85 A;
260 A for the model of 130 A;
400 A for the models from
171 and 200 A.
824 for the models from 255 A to
412 A.
The time programmed for the
acceleration ramp is shorter than the
actual acceleration time.
Nominal motor current higher than
the current that can be supported by
the Soft-Starter.
Motor shaft is locked, rotor blocked.
Power-on.
Reset key.
Auto-reset.
DIx.
Frequency out
of tolerance
E75
(LED Fault)
Flashes once
(LED Ready)
Off
When the limit is higher or lower
than the limits of 45 to 66 Hz.
The line frequency is out of range.
When the Soft-Starter + motor are
being supplied by a generator that
is not supporting the full load or the
start of the motor.
Power-on.
Reset key.
Auto-reset.
DIx.
Closed By-pass
contact or
shorted SCR’s
E77
(Fault LED)
flashes 6 times
(Ready LED) is
off
When there is no opening of the
internal By-pass contact circuit.
Bad contact in the relay activation
cables, at either internal or external
By-pass.
Defective contacts due to an
overload.
A short-circuit in parallel or external.
Power-on.
Reset key.
DIx.
table 6.1
- Faults and possible causes (cont.)