ABB DCS550 - Page 297

297
Fault tracing
3ADW000379R0501 DCS550 Manual e e
7-segment
display
Text on DCS
Control Panel
and DWL
Definition / Action
Alarm-
word
Alarm is
active when
Alarmlevel
ArmCurRipple
One or several thyristors may carry no current. Check:
−
CurRippleSel (30.18), CurRippleLim (30.19)
−
for too high gain of current controller [M1KpArmCur
(43.06)]
−
current feedback with oscilloscope (6 pulses within one
cycle visible?)
−
thyristor gate-cathode resistance
− thyristor gate connection
bit 0
A121
121 AutotuneFail
Autotuning failed:
For more
details, check Diagnosis (9.11). To clear the
alarm set
ServiceMode (99.06) = NormalMode or
WinderTuning (61.21) = NotUsed
9.07,
bit 4
always
4
A123
123 FaultSuppres
Fault suppressed:
At least one fault message is
currently active and
suppressed.
9.07,
bit 6
always
4
A124
124
SpeedScale
Speed scaling out of range:
The parameters causing the alarm can be identified in
Diagnosis (9.11)
. α is set to 150°; single firing pulses.
Check:
−
M1SpeedMin (20.01), M1SpeedMax (20.02),
M1SpeedScale (50.01), M1BaseSpeed (99.04)
9.07,
bit 7
always
3
A125
125 SpeedFb
Speed feedback:
The comparison of the speed feedback from pulse
encoder or analog tacho has failed.
Check:
−
M1SpeedFbSel (50.03), SpeedFbFltMode (30.36),
SpeedFbFltSel (30.17), EMF FbMonLev (30.15),
SpeedFbMonLev (30.14)
−
pulse encoder: encoder itself, alignment, cabling,
coupling, power supply (feedback might be too low),
mechanical disturbances jumper S4 on SDCS-CON-F
−
analog tacho: tacho itself, tacho polarity and voltage,
alignment, cabling, coupling, mechanical disturbances,
jumper S1 on SDCS-CON-F
−
EMF: connection converter - armature circuit closed
− SDCS-CON-F
9.07,
bit 8
always
4
A126
126 ExternalDI
External alarm via binary input:
There is no problem with the drive itself!
Check:
−
ExtAlarmSel (30.32), alarm = 0, ExtAlarmOnSel
(30.34)
9.07,
bit 9
always
4
A127
127 AIRange
Analog input range:
Undershoot of one of the analog input values under 4mA /
2V.
Check:
−
AI Mon4mA (30.29)
−
used analog inputs connections and cables
− polarity of connection
9.07,
bit 10
always
4
A128
128 FieldBusCom
Fieldbus communication loss:
F528 FieldBusCom
is only activated after the first data
set from the overriding control is received by the drive.
Before the first data
set is received, only A128
FieldBusCom
is active. The reason is to suppress
unnecessary faults (the start up of the overriding control is
9.07,
bit 11
always if FB
TimeOut
(30.35)
≠ 0
4