Thomas NOMARK 65/99 - Page 51

Indicators Error number Cause Remedy
Voltmeter
Display
E 1
Gun trigger pressed at machine
switch ON
Check gun trigger
E71
Weld SCR defect
E72
Capacitors are not charging Check fuse or overheat of
the machine
E73
Capacitors are still charged when
unit is switched ON
E74
Main relay defect
E75
Defect charging SCR
E76
Capacitors are not charging during
the test when unit is switched ON
Check fuse or overheat of
the machine
E77
Capacitors are discharging too
fast.
Check Main relay and the
discharge resistances.
E78
No weld (no discharge) - Weld SCR defect.
- Control Board defect
- Bad electrical contact in the
welding circuit (gun/plate)
E79
Capacitors voltage is too high (>
210 v)
Tab: 5 – 1b Troubleshooting using Voltmeter LED display
Malfunction or
change
Situation Cause Remedy
Charging cycle
takes
longer
Temperature NOMARK
is high
Clear air slots of NOMARK 65/99 if
appropriate; keep adequate
distance between NOMARK and
other objects; remove heat sources
from environs; shield
against heat radiation
Welding is not
Started
No welding element in
chuck (LED "contact"
off)
Insert welding element in chuck and
repeat welding
Welding is not
Started
Welding element does
not have
an ignition tip
Insert welding element with ignition
top in Chuck and repeat welding
Welding is not
Started
Control cable defective Check control cable and replace if
necessary
Welding is not
Started
Gun micro switch
defective
Check micro switch and replace if
necessary
Welding is not
started
Control board defective Replace control board*) or notify
TWS Tech after sales service
*) Check only by electricians!
Tab: 5 - 2 Defective welds or malfunctions
Note: Never weld with an overlarge or expanded Chuck because the Chuck will be damaged.
50
• Never weld without stud because the Chuck will then also be damaged.