background image

Operating principal

VDC

t

105

13µs

Ma

x.

 0,5

n. + 320 V

1/3

V1

V2

When IGBT-transistors V1 and V2 are not conductive, no power is transferred. The power is 
adjusted by changing the IGBT-transistors  conductive timings (PWM).

Main circuit

+ t

+ t

X3

X1

X2

R6

9

R7

0

L2

C2

8

C2

2

C5

L1

R59

R54

C4

3

V26

V

23

V9

C1

, C2

, C3

V5,

 V3

2

V1,

 V

31

V2,

 V

3,

 V4

V6

, V

7,

 V8

T00

1

T2

K1

T0

01

U

R64

U

V29, V30

C39

R65

R6

6

C3

8

V2

7,

 V2

8

R6

3

X18

X17

L001

L002

X003

X004

X16

X3

X2

Z001

Minarc power sources are ”dual-Forward”-inverter power sources, controlled by PWM method. 
The switching components are IGBT-transistors. Inverter operating frequency is approx. 80 kHz. 
Below is a picture of the ”dual-forward”-inverter operating principal:

4

Summary of Contents for miniarc 110

Page 1: ...Troubleshooting guide Ver 1 0 ...

Page 2: ...rings Measuring points Main transformer T001 prim Voltage Main transformer T001 sec Voltage Voltage after secondary rectifier IGBT gate pulse Control card A001 connectors Control card A001 layout IGBT transistor testing Secondary diodes testing Service infos Notes 3 4 4 5 6 7 7 8 8 9 9 10 10 11 11 13 14 15 16 17 17 18 20 21 ...

Page 3: ... 1 5 2 5 mm Welding current adjustment Portaaton Portaaton OCV 105 V 105 V Idling power 10W 10W Efficiency 0 8 0 8 Power factor 0 60 140 A 25 5 V 0 60 110 A 24 4 V Temperature class B 130 C H 180 C B 130 C H 180 C Operating temperature 20 40 C 20 40 C Stock temperature 40 60 C 40 60 C Casing class IP 23C IP 23C Norms IEC 974 1 IEC 974 1 EN 50199 EN 50199 Measures Length 305 mm 305 mm Width 123 mm ...

Page 4: ... R69 R70 L2 C28 C22 C5 L1 R59 R54 C43 V26 V23 V9 C1 C2 C3 V5 V32 V1 V31 V2 V3 V4 V6 V7 V8 T001 T2 K1 T001 U R64 U V29 V30 C39 R65 R66 C38 V27 V28 R63 X18 X17 L001 L002 X003 X004 X16 X3 X2 Z001 Minarc power sources are dual Forward inverter power sources controlled by PWM method The switching components are IGBT transistors Inverter operating frequency is approx 80 kHz Below is a picture of the dua...

Page 5: ...ere is a short circuit in the primary side Replace the faulty power semiconductor See IGBT transistor testing page 17 Diode V24 is in short circuit on control card A001 Check the diode and replace if needed Faulty control card A001 Replace control card A001 The power source starts and the OCV rises to 85 V after which the power source shuts down The power source can t be loaded Relay K1 Check the ...

Page 6: ...Main circuit diagrams Main circuit diagram from serial number 1085088 M onwards OCV approx 85 V Main circuit diagram before serial number 1085088 M OCV approx 105 V 6 ...

Page 7: ...nctional tests measurings 1 2 3 Measuring point 1 Main transformer T001 primary voltage Measuring point 2 Main transformer T001 secondary voltage Measuring point 3 Voltage after the secondary rectifier 7 ...

Page 8: ...Measuring points on the control card A001 Main tranformer T001 primary voltage 10 A Measuring point 1 Main tranformer T001 primary voltage 1 2 3 4 8 ...

Page 9: ...Päämuuntajan T001 ensiöjännite 140 A Measuring point 2 Main transformer T001 secondary voltage Main tranformer T001 secondary voltage 10 A Measuring point 1 Main transformer T001 primary voltage 9 ...

Page 10: ...Main transfomer T001 secondary voltage 140 A Measuring point 3 Voltage after secondary rectifier Voltage after the secondary rectifier 10 A Measuring point 2 Main transformer T001 secondary voltage 10 ...

Page 11: ...Measuring point 4 IGBT gate pulse IGBT gate pulse 10 A Measuring point 3 Voltage after the secondary rectifier Voltage after the secondary rectifier 140 A 11 ...

Page 12: ...IGBT gate pulse 140 A IGBT gate pulse 60 A Measuring point 4 IGBT gate pulse 12 ...

Page 13: ...IGBT gate pulse with open circuit OCV approx 105 V Measuring point 4 IGBT gate pulse IGBT gate pulse with open circuit OCV approx 85 V 13 ...

Page 14: ...ective earth X4 X6 X8 Current adjustment potentiometer R001 X5 X7 MMA TIG selection switch S002 X9 X11 Main transformer T001 auxiliary coil X10 X12 Main transformer T001 PTC RT101 X13 X14 Primary profile PTC RG201 X15 Fan X16 X17 Main transformer T001 secondary X18 Secondary choke L001 X19 X20 Main transformer T001 primary X23 PWM circuit N1 VFB pin 2 X24 5 V 14 ...

Page 15: ...Control card A001 layout X4 The older version control card A001 4292730 The new control card A001 4298870 15 ...

Page 16: ... filter Intermediate circuit charging Rele 9766230 Rectifier unit 9750191 Smoothing capacitors 9755615 IGBTs and opposite diodes IGBT set 4297750 Secondary rectifier unit 4297740 LED 9775757 Varistors 95 V 9753590 175 V 9753588 16 ...

Page 17: ...tening torque to the heatsink is 0 6 1 2 Nm Testing the secondary diodes When testing the secondary diodes the other coil end of the main transformer T001 has to be disconnected The main transfomer coils and connectors may not be bent If the secondary diodes are in short circuit the power source doesn t start Secondary rectifier unit 4297740 The tightening torque for the secondary diodes is 0 6 1 ...

Page 18: ...Reason for midification Secondary choke may cause a short circuit between plus and minus poles This is prevented by installing the inslulator 9771963 to the minus pole Production The modification is valid from serial number 1023532 K onwards Power sources with serial number before 1027716 K The modification can be carried out during service or repair work 18 ...

Page 19: ... if one resistor has been destroyed then the IGBT doesn t get gate control and this causes overload to the other IGBTs When IGBTs are replaced then the gate resistors must be checked too See the attached picture DC link Intermediate circuit charging relay K1 9766230 If fan rotating speed drops after the machine starts and the OCV is max 85 volts then most likely the DC link charging relay is not w...

Page 20: ... card Z001 4298600 lowers the OCV to 85 Volts See the chart below Power source Control card A001 Filter card Z001 OCV MINARC 140 4298870 new version 4298600 new version 85 VDC MINARC 140 4298870 new version 4294620 old version 105 VDC MINARC 140 4292730 old version 4298600 new version 105 VDC MINARC 110 4301880 new version 4298600 new version 85 VDC MINARC 110 4301880 new version 4294620 old versi...

Page 21: ...Notes 21 ...

Reviews: