Localization Of Errors; Check Of Starting Procedure; General Inspection Of The Machine; Testing The Live (Switched-On) Machine - Fronius TRANSPOCKET 1400 MV Serviceanleitung

LOCALIZATION OF ERRORS

CHECK OF STARTING PROCEDURE

- mains voltage will be identified
- link electrolytic capacitor will be loaded by the PTC
- at 230V DC ð switched-mode power supply is ON
- green LED is ON
yellow LED flashes (identification of undervoltage)
- yellow LED goes out ð delay relay is ON
- after 0,6 sec. driver is ON

GENERAL INSPECTION OF THE MACHINE

The following measurements must be made:
(see measuring points, fig.3, 4)
a) Transistor V16 ð responsible for switched-mode power supply (fig. ).
Measure the diode gap (0.4 - 0.7 V) between Drain and Source (D and
S). When performing this measurement, take care with +/- polarity!
N.B.: If this component is faulty, please replace the entire board, as in most
cases other components will have been destroyed as well.
b) Transistor-module (fig. )
Measure the diode gap of the transistor-module.
Out1 - U+ = 0.4 - 0.7V
Out2 - U+ = 0.4 - 0.7V
Gnd - Out1 = 0.4 - 0.7V
Gnd - Out2 = 0.4 - 0.7V
c) Varistor (fig. )
Measure the resistance between the two points shown (R = ∞). Check
the PTC 420 resistance as well (approx. 150Ω at 25°C)
d) Primäry rectifier (fig. )
Measure the diode gap (0,4 - 0,7V) between the two points shown. When
performing this measurement, take care with +/- polarity!
N.B.: If the value is noticeably lower, then one of the transistors may be
defective.
e) Secondary rectifier (fig. )
Measure the diode gap (0.2 - 0.3 V) between the points shown. Take care
with +/- polarity when performing this measurement! If these components
are OK, you can move onto the next step - testing the live (switched-on)
machine.

TESTING THE LIVE (SWITCHED-ON) MACHINE

Check U at manual welding mode.
[Soll]
By turning the welding current dial to 140 ampere.
The brightness of the diode V24 changes with the commande value.
Take the measurement of the voltage [Drain-Source], U
transistor V16 (see measuring points, figure
Fig.1 Voltage [Drain-Source] = U
Take the measurement of the gate voltage
(see measuring points, figure
GND - G2, GND - G4, Out1 - G1, Out2 - G3
All 4 measurements must be identical. If the amplitude and the forward signal
are different, the module is defect.
Fig.2 Gate voltage
6
)
100 V / DIV
5µS / DIV
of the transistor V16
[DS]
)
5 V / DIV
2µS / DIV
of the
[DS]