Service Manual Ver VRD

Transcription

1 Service Manual Ver VRD 151

2 Contents Technical data Operation principle. 4 Main circuit Troubleshooting diagram... 7 Main ciruit diagrams. Block diagram... Operational tests / measurings Measurings Main transformer T001 prim. voltage... Main transformer T001 sec. voltage... Voltage after sec. rectifier , Auxiliary coil voltage Fan M001 voltage Pole voltage in OCV.... Measuring points in the flat cable..... Gate control, upper IGBTs.... Gate control, lower IGBTs.... Aux. voltage in DC-link.... Signal lamp H2 control / VRD ON Main circuit card Z001 connectors Main circuit card Z001 layout Control card A001 layout Structure.. 24, 25 IGBT-transistor testing Sec. diode testing Notes

3 Technical data Minarc 150 Minarc 150 VRD Minarc 151 Supply voltage, 1~ 50/60 Hz 230 V ± 15% 230 V ± 15% 110 V ± 15% Loadability 35% ED (MMA) 140 A (7,5 kva) 140 A (7,5 kva) 140 A (7,5 kva) 100% ED (MMA) 100 A (5,1 kva) 100 A (5,1 kva) 100 A (5,1 kva) 35% ED (TIG) 150 A (5,0 kva) 150 A (5,0 kva) 150 A (5,0 kva) 100% ED (TIG) 110 A (3,3 kva) 110 A (3,3 kva) 110 A (3,3 kva) Supply cable / fuses 2,5 mm² S / 3,3 m 16 A 2,5 mm² S / 3,3 m 16 A 6 mm² S / 2,0 m 32 A Welding current range (MMA) 10 A / 20,5 V 140 A / 25,6 V 10 A / 20,5 V 140 A / 25,6 V 10 A / 20,5 V 140 A / 25,6 V Suitable stick sizes ø 1,5 3,25 mm ø 1,5 3,25 mm ø 1,5 3,25 mm Welding power adj. Stepless Stepless Stepless OCV ~ + 85 V ~ + 30 V ~ + 85 V Idling power < 10W < 10W < 10W Efficiency 0,8 0,8 0,8 Power factor 0,60 (140 A / 25.5 V) 0,60 (140 A / 25.5 V) 0,60 (140 A / 25.5 V) Temperature class B (130 C) / H (180 C) B (130 C) / H (180 C) B (130 C) / H (180 C) Operation temperature range C C C Stock temperature range C C C Casing class IP 23C IP 23C IP 23C Norms IEC , -10 IEC , -10 IEC EN EN EN Dimensions Length 320 mm 320 mm 320 mm Width 123 mm 123 mm 123 mm Height 265 mm 265 mm 265 mm Weight 4,0 (4,6) kg 4,0 (4,6) kg 4,4 (5,2) kg 3

4 Operation principle Minarc power sources are dual-forward inverters, controlled by PWM technology. Switching components are IGBT transistors. The operation frequency is ~ 80 khz. Below is a picture of the dual-forward inverter operation principle. ~ V 105 VDC V1 Max. 0,5 1/3 13µs t V2 When IGBTs V1 and V2 are non-conductive no power is transferred. Power is altered by changing the transistor s timing (PWM). Main circuit X11/12 R9 X1 X3 R31 R32 V21 V20 + t + t C15 L2 C5 C9 V16 L1 C13 V11 C2, C3, C4 V7, V3 V4, V5, V6 T001 X13 X12 R30 R23 C10 V1, V2 T2 X5 K1 V8, V9, V10 Primary circuit connection, Minarc 150/150 VRD. 4

5 Main circuit R14 X11/7 R17 R13 R8 X11/12 R9 X2 L1 L2 C2, C3 V6, V2 R24 C16 C9 V10 X3 X5 C10 V1, V11 C21 R34 V28, V29 X7 L001 X003 R21 V7, V8, V9 R20 V3, V4, V5 T001 T2 V16 C11 X1 X13 X12 X4 C4, C5 Primary circuit connection, Minarc 151. X6 U V24 V25 T001 R35 R37 C20 V26, V27 U R33 V26 X8 X11/11 X9 X004 V19 R11 V30 V28 X11/14 V22 X10 X11/15 V23 C16 X21 V18 X5 C18 V22 R29 R24 R25 C14 C17 C19 R27 R36 X22 Secondary circuit connection, Minarc 150/151. 5

6 Main circuit C21 R34 V28, V29 X7 L001 X003 R21 R20 X6 U V24 V25 T001 R35 R37 C20 V26, V27 U R33 V26 X8 X11/11 X9 X004 V19 R11 V30 V28 X11/14 V22 X10 X11/15 V23 C16 X21 V18 X5 C18 V22 R29 R24 R25 C14 C17 C19 R27 R36 X22 Secondary circuit connection, Minarc 150 VRD. 6

7 General This machine may be repaired only by authorized repair shops and persons! The visual check must be done first, to find possible damages; loose wires, breaks and signs of overheating. Troubleshooting diagram DISTURBANCE POSSIBLE CAUSE REMEDY Power source doesn t start; OCV ~ 0 V; Cooling fan M001 Disconnect the fan connector X20 and start the power source again. If the power source starts and the OCV is ok, change the fan. The power source starts and the OCV rises up to ~85 V, after which the power source shuts down. Th epower source can not be loaded. The automatic fuses are blown during start up. The rectifier diodes are in short circuit. Check the secondary diodes condition and change if needed. See the changing of secondary diodes, page 26. Faulty primary circuit power Check the primary side power semiconductor. semiconductors. If the voltage over the PTC R30 is more than ~ 230 Vac then there is a short circuit in the primary circuit. Change the faulty power semiconductor. See the IGBT transistor testing on page 26. Faulty control card A001. Change the control card A001. Relay K1 Check the relay operation. Welding current can t be adjusted by potentiometer R001. Faulty power adjustment potentiometer R001. Check the potentiometer condition (R001 = 10 kω) Faulty control card A001. Change control card A001. 7

8 Main circuit diagrams Minarc 150/150 VRD Minarc 151 8

9 Block diagram A001 Controller (PWM) Gate buffer Set value circuit Voltage watch MMA ignition MMA dynamics Temperature control Supply voltage watch Auxiliary voltage watch TIG-locking TIG-scaling 16 Z001 Power stage EMI-filter DC-link charging Aux. voltages Voltage reserve circuit OCV controller Overvoltage protection 4 Z002 Relaycard Minarc 151 9

10 Operational tests / measurings C F E B A D Measuring point A. Main transformer T001 primary voltage Measuring point B. Main transformer T001 secondary voltage Measuring point C. Voltage after seconday rectifier Measuring point D. Aux. coil voltage Measuring point E. Fan M001 voltage Measuring point F. Pole voltage 10

11 Measuring points on main circuit card Z001 (Minarc 150) D E C B A A B C D E Main transformer T001 primary Main transformer T001 secondary After the rectifier Main transformer auxiliary coil Fan M001 11

12 Measuring point A. Main transformer T001 primary voltage Main transformer T001 primary voltage, min. (MMA) Main transformer T001 primary voltage, max. (MMA) 12

13 Measuring point B. Main transformer T001 secondary voltage Main transformer T001 secondary voltage, min. (MMA) Main transformer T001 secondary voltage, max. (MMA) 13

14 Measuring point C. Voltage after secondary rectifier Voltage after secondary rectifier, min. (MMA) Voltage after secondary rectifier, max. (puikko) 14

15 Measuring point D. Auxiliary coil voltage Auxiliary coil voltage, min. (MMA) Auxiliary coil voltage, max. (MMA) 15

16 Measuring point E. Fan voltage Idling Min. load Max. load Measuring point F. Pole voltage on idling Power adj. Potentiometer, min. Power adj. Potentiometer, max. 16

17 Measuring point on the flat cable G H I J X1/1 GND X1/2 Current info from primary X1/3 GND X1/4 Gate control, upper IGBTs X1/5 Gate control, lower IGBTs X1/6 GND X1/7 Supply voltage watch X1/8 Temperature watch (PTC:t) X1/9 GND X1/10 Auxiliary voltage ( V) X1/11 Signal lamp H2 control / VRD X1/12 Auxiliary voltage from DC-link X1/13 GND X1/14 Auxiliary voltage +20 V X1/15 OCV control (~ +85 V) X1/16 GND 17

18 Measuring point G. Gate control, upper IGBTs Gate pulse, min. (MMA) Gate pulse, max. (MMA) 18

19 Measuring point H. Gate control, lower IGBTs Gate pulse, min. (MMA) Gate pulse, max. (MMA) 19

20 Measuring point I. Auxiliary voltage from DC-link Measuring point J. Signal lamp H2 control / VRD ON 20

21 Main circuit card Z001 connectors (Minarc 150) X21 X22 X9 X15 X16 X17 X18 X14 X19 X20 X8 X13 X7 X10 X6 X11 X12 X1 X3 X5 X1, X3 Supply voltage X5 Protective earth X6, X8 Main transformer T001 sec. X7 Sec. Choke L001 (+) X9 X004 (-) X10 X003 (+) X11 Connection, A001 X12, X13 Main transformer T001 primary X14, X15 Main transformer T001 auxiliary coil X16, X17 PTC RT101 X18, X19 PTC RZ101 X20/1, 2 Fan M001 X21 X003 (+) X22 X004 (-) 21

22 Main circuit card Z001 layout (Minarc 150) Main transformer X10 Smoothing capacitors Secondary rectifier X11 EMI Primary rectifier EMI, DC-link charging X1, X3 LZ101 X5 22

23 Control card A001 layout X1 S1 MMA/TIG N1 Voltage regulator (+ 20 V) N2 PWM-circuit R26 Max. current adjustment R35 Min. current adjustment H2 ON / VRD ON H1 Overheat protection N3 Comparator R49 Current adjustment N4 Comparator 23

24 Structure Z001 A001 3 mm T10 T15 T25 24

25 Structure Extracting the control card A001 25

26 IGBT-transistor testing Discrete-IGBTs (50 A, 600 V) can be tested with an IGBT tester. When changing damaged IGBTs, the whole series must be changed, plus the gate resistors (10Ω)!! G C E Discrete-IGBT s tightening torque to the heatsink is 0,6 1,2 Nm! B2/6 C2E1/1 E2/2 C1/3 B1/4 OFF ON CONTROL TR 1 TR 2 IGBT-TESTER Secondary diode testing When testing secondary diodes the other coil end of the main transformer (T001) must be disconnected. Main transformer cable connector s may break if bent! If secondary diodes are in short circuit, then the power source will not start. The tightening torque for the secondary diodes is 0,6 1,2 Nm! The soldering must be done carefully, because they are stressed with high current, approximately 30 A/ leg! 26

27 Notes 27