Classe-CA400-pwr-sm维修电路原理图.pdf

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1、PRO-SVR_LEGACY Page 1 of 14 Date: August 8, 2007 Model Number: CA-400 Class Audio Inc. Subject: Service manual Class Audio, Inc. 5070 Franois Cusson Lachine, Qubec Canada H8T1B3, RadioFans.CN 收音机爱 好者资料库 PRO-SVR_LEGACY Page 2 of 14 Table of Contents Introduction 3 Important Notes on Servicing 3 Order

2、ing Replacement Parts 3 Block Diagrams 4 Start up Procedure 5 Protection Modes and Indicators 6 Troubleshooting Guide 7 Output Transistors Testing and Replacement 8 Calibrations and Adjustments 9 Parts List 10 Updates 11 Fuses 13 Voltage Change 13 Remote Interface Information 14 Schematics 15 The co

3、ntents of this document as well as the files associated with it contain confidential information that is proprietary to Class Audio Incorporated and are intended solely for the purpose of servicing product. No part of its contents may be used, copied, disclosed, or conveyed to any party in any manne

4、r whatsoever without prior written permission from Class Audio Incorporated. RadioFans.CN 收音机爱 好者资料库 PRO-SVR_LEGACY Page 3 of 14 Introduction Please read this manual carefully before commencing servicing! Only qualified and authorized personnel should attempt to service this product. The lightning f

5、lash with arrowhead symbol, within an equilateral triangle, is intended to alert the user to the presence of uninsulated dangerous voltage within the products enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons. The exclamation point within an equilateral

6、triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions. Class has a global product support network. For product assistance or to order replacement parts please contact your nearest service center always quoting the unit serial number. N

7、orth America Phone: (978) 664-2870 E-mail: Europe Phone: 44 (0) 1903 221 700 E-mail: Asia Phone: (852) 2790 8903 E-mail: classebwgroup.hk Rest of the World Phone: (514) 636-6384 E-mail: Important Notes on Servicing 1.ALWAYS observe ESD precautions when handling electronic modules or PCBAs. 2.NEVER e

8、xchange boards with a different revision number, unless authorized by Class. 3.ALWAYS use Class original replacement parts. The use of generic parts may void the warranty of the unit. Ordering Replacement Parts There may be a delay in processing incomplete requests. Please be sure to include all req

9、uired information. Remember to quote the serial number of the unit on all replacement part orders and the Class order number when returning defective parts for credit. PRO-SVR_LEGACY Page 4 of 14 Block diagrams PRO-SVR_LEGACY Page 5 of 14 Start Up Procedure When receiving a unit, an assiduous visual

10、 inspection must be performed. Do not connect the unit without analysing the symptoms reported by the customer and the results of the inspection. Using the troubleshooting guide, find the problem and proceed to the repair. Once this step is done, follow these steps, known as the start-up procedure,

11、to ensure that everything in the unit is in working condition. 1. Proceed with a post repair visual inspection. Take the time to check if every wire is reconnected properly, every screw is bolted on, no soldering and/or metal residues lying in the unit, every fuse has been replaced, etc. 2. Connect

12、the unit to a variable transformer, setted to 0Vac. 3. Turn the bias trimpot (RV102) counter clockwise until a click is heard. 4. Connect the bypass wire to the variable transformer. This bypass is a power cord, modified on the female side in order to bypass the soft start sequence. It is connected

13、to the line ring on voltage selector PCB. 5. Slowly raise the voltage to 10Vac, and check positive and negative rails and pre-driver supply. Check fuses. 6. If one or more supply are not within specifications, return to the troubleshooting guide. 7. Slowly raise voltage until you hear relays click,

14、this point is around 55Vac. Recheck every supply. 8. If one or more supply are not within specifications, return to the troubleshooting guide. 9. Raise voltage to 120Vac. Recheck every supply 10. If every supply is within specifications, unplug the unit and bypass from the variable transformer. Reco

15、nnect only the unit. 11. Report to Calibration and adjusments (section 9) to adjust bias and DC offset. Note that bias can be adjusted to 14mV, and the following tests can be performed before the unit is send to the burn-in bench for a 24 hours warm-up. 12. Connect the unit to a load, and to a sourc

16、e using balanced inputs and single ended inputs, independently. 13. Perform a test with a 200Hz, a 2kHz and a 20kHz tone, both sinus wave and square wave. Check the output with a oscilloscope, on 4 ohms and 8 ohms loads. Take special cares about oscillation and phase correlation between channels. 14

17、. Connect the unit to a small speaker, and short the input. Check for any noise. Perform this step with single ended inputs and balanced inputs, independently. 15. Put the unit on a burn-in bench, and let it sit for 24 hours, then readjust bias. Let the unit on the burn- in bench for another 72 hour

18、s. 16. Redo steps 11 to 14 before shipping to the customer. PRO-SVR_LEGACY Page 6 of 14 Protection Modes and Indicators The front LED shows the status of the amplifier. When starting up normally, the CA400 will show a FLASHING RED LED for about 15 seconds and if all is normal, the LED will go SOLID

19、RED. If there is a fault, the LED will go to a FLASHING GREEN LED. The CA400 is equipped, except for some early production models, with four rails protection fuses. In the event that one or more of these fuses would blow, the technician will first need to identify and cure the cause of failure (plea

20、se report to troubleshooting guide). When the cause has been identified, disconnect the unit from the system including the AC power. Remove the top cover and look for damaged or burned components. If no other components than the fuses appear to be damaged, the technician can then replace the broken

21、fuses with the same value and rating (please report to fuses section). The rail fuses are located on each device board. When replacing fuses, please make sure that the fuse holder are holding the fuses very tightly. A loose fuse holder can translate into distortion on top of the signal. PRO-SVR_LEGA

22、CY Page 7 of 14 Troubleshooting Guide Symptom Possible cause Unit won t turn on Check connections; Check fuses; Check soft-start circuit; Check relays; Check power supply circuits (positive rail, negative rail, Mosfet supply). Smoked and/or burned components Check for short between components and gr

23、ound; Check output transistors; Check output relays; Check power supply circuits (positive rail, negative rail, Mosfet supply). Blown fuses Check for short between fuse and ground; Check power supply circuits (positive rail, negative rail, Mosfet supply). No output Check connexions; Check output rel

24、ays; Check power supply circuits (positive rail, negative rail, Mosfet supply); Check output transistors. Unit turn into protection Check for smoked and/or burned components; Check power supply circuits (positive rail, negative rail, Mosfet supply); Check source and load; Check protection circuit; C

25、heck sensor wires between sensor PCB and control PCB; Check outputs transistors and Mosfet drivers. Excessive buzz and/or hum Check electrical lines; Check for a ground loop in the system. Oscillation Check source; Check capacitors on main board; Check 4.7? resistor. Intermittent signal Check connec

26、tions; Replace shield wires. PRO-SVR_LEGACY Page 8 of 14 Output Transistors Testing and Replacement PLEASE NOTE THAT THESE TESTS ARE ONLY EFFECTIVE ON BIPOLAR TRANSISTORS. DO NOT PERFORM THESE TESTS ON MOSFET DEVICES, AS THEY ARE LIKELY TO BECOME SHORT DURING THE TEST. You should check all pin combi

27、naisons, as there is a chance that only one side of the transistor is short. When replacing outputs transistors, the technician should first disconnect both outputs and main board to check if the blown outputs were caused by a faulty component on the amplifier s base. Blown output transistors should

28、 be replaced by kits, not individually. These kits contains matched transistors for both rails of one channel. When replacing blown output transistors, you must also replace positive and negative Mosfet drivers and bias transistor. Carefully inspect 4.7? resistor and 10? soft start resistor, and rep

29、lace if necessary. Replace any burnt component or board. Pins : 1 Base 2 Emitter Case Collector You should have these results, if the transistor is good. MJ21194 (NPN) Positive lead Negative lead Result B C Conductive B E Conductive C B Infinite C E Infinite E B Infinite E C Infinite MJ21193 (PNP) P

30、ositive lead Negative lead Result B C Infinite B E Infinite C B Conductive C E Infinite E B Conductive E C Infinite PRO-SVR_LEGACY Page 9 of 14 Calibrations and Adjustments Bias adjustment: Note: Bias adjustment should be made without any load connected to the amplifier s output, and no signal conne

31、cted to the amplifier s input. 1. Connect a multimeter to R1 leads and set the multimeter to mV scale. 2. Turn trimpot RV102 counterclockwise until it reaches 0?. A click should be heard. 3. Turn on amplifier, and let it warm up for 15 minutes on idle. 4. Adjust trimpot RV102 to get a 14mV reading.

32、5. Let the amplifier warm up for a 24 hours period with signal and load. 6. Remove signal and load, and reconnect the multimeter, setted to mV scale, to R8 leads. Note the reading. 7. Connect the multimeter to R2, R3, R4, R5 and R6 leads. Note the readings. 8. Input the results into this formula: (1

33、44 mVR1 mVR2 mVR3 mVR4 mVR5 mVR6) 6) + mVR1 9. Connect the multimeter to R8 leads, and adjust RV1 to match the reading to the formula result. 10. Results should be around 24mV. DC offset: Note: DC offset adjustment should be made without any load connected to the amplifier s output, and no signal co

34、nnected to the amplifier s input. 1. Connect a multimeter to the output binding posts and set the multimeter to mV scale. 2. Adjust trimpot RV101 in order to reach 0mV. It is easier to turn the trimpot turn at a time, and let DC offset stabilize in order to get an accurate reading. 3. A tolerance of

35、 1mV is acceptable. PRO-SVR_LEGACY Page 10 of 14 Parts List This is not a detailed part list. It is a list of major chassis parts and PCBs. If you need to order a specific part, please contact Classe Audio with the part location, PCB number, and model and serial number of the unit. If you need a com

36、plete PCB, please replace the (x) in the Classe part number with the revision number printed on the board. Parts Description Classe part number B01AX Complete PCB, relay B01AXR(x) B01CX Complete PCB, power switch B01CXR(x) B01DX Complete PCB, remote B01DXR(x) B01GX Complete PCB, filter B01GXR(x) B01

37、1X Complete PCB, amplifier B011XR(x) B012X Complete PCB, capacitor B012XR(x) B013X Complete PCB, protection B013XR(x) B014X Complete PCB, supply B014XR(x) B015X Complete PCB, input B015XR(x) B016X Complete PCB, AC inlet B016XR(x) B017X Complete PCB, output, top / bottom B017XR(x) B018X Complete PCB,

38、 output, middle B018XR(x) PRO-SVR_LEGACY Page 11 of 14 Updates 1. On board B018X (both PCBs), replace R132 with Classe part number A211-1004. 2. On chassis, install PCB filter (noise elimination module) B01GX, using the following instructions. Noise elimination module: EXTRA PRECAUTIONS SHOULD BE TA

39、KEN WHEN REPAIRING, MODIFYING,OR TROUBLESHOOTING IN THE POWER SUPPLY AREA. UNIT MUST BE DISCONNECT FROM MAIN SOURCE AND CAPACITORS MUST BE DISCHARGED USING A 100W INCANDESCENT BULB. 1. Remove top cover, handles and faceplate (for more information about mechanical disassembly and reassembly, report t

40、o section 2, mechanical assembly) 2. Turn the unit upside down, front of the unit facing you 3. Using a pencil, make a mark at 3” from the back of the unit, 5” from the ride side. Use a punch to guide the drill bit. 4. Using a 1/8” drill bit, drill a hole at this intersection.Clean the area for any

41、metal residue. 5. Remove two black screws holding the voltage selector PCB 6. Disconnect the wire from N (neutral). The wire should be yellow or clear. Take time to identify each wire in order to reconnect them properly. 7. Disconnect wire from L (live). The wire should be blue or black. Identify th

42、is wire. 8. Gently strip off the black shrink tubing covering both wires. 9. Cut N wire about 4 inches (10.2cm) from the edge of the lower portion of the supply PCB 10. Connect N wire to one end of the noise filter board, Classe part number B01GXR01. (Fig. 1) 11. Using the wire supplied with the kit

43、, connect the other end of the noise filter board. (Fig. 1) 12. Fix the board to the chassis, using the screws supplied with the kit. 13. Install the heat shrink tubing supplied on N (new wire) and L wires 14. Reconnect both wires to the voltage selector PCB 15. Clean and spotcheck connections 16. R

44、eassemble and test unit carefully for proper operation. PRO-SVR_LEGACY Page 12 of 14 Updates fig. 1 PRO-SVR_LEGACY Page 13 of 14 Fuses EXTRA PRECAUTIONS SHOULD BE TAKEN WHEN REPAIRING, MODIFYING,OR TROUBLESHOOTING IN THE POWER SUPPLY AREA. UNIT MUST BE DISCONNECT FROM MAIN SOURCE AND CAPACITORS MUST

45、 BE DISCHARGED USING A 100W INCANDESCENT BULB. WHEN REPLACING FUSES, PLEASE MAKE SURE THAT THE FUSE HOLDERS ARE HOLDING THE FUSES VERY TIGHTLY. A LOOSE FUSE HOLDER CAN TRANSLATE INTO DISTORTION ON TOP OF THE SIGNAL. Main fuses: For 100 120v units: 15A slo-blo, Classe part number MDA-15A For 220 240v

46、 units: 12A slo-blo, Classe part number MDA-12A The main fuse is located at the back of the unit, on the rear panel. Rail fuses: 15A, Classe part number GDB-15A The rail fuses are located on the device boards. Mosfet fuses: 0.75A, Classe part number 225.750 The Mosfet fuses are located on top of the

47、 main board. Voltage Change EXTRA PRECAUTIONS SHOULD BE TAKEN WHEN REPAIRING, MODIFYING, OR TROUBLESHOOTING IN THE POWER SUPPLY AREA. UNIT MUST BE DISCONNECT FROM MAIN SOURCE AND CAPACITORS MUST BE DISCHARGED USING A 100W INCANDESCENT BULB. 1. Set the jumper position according to the table below. 2.

48、 Replace the varistor, according to new line voltage, following Classe s recommendations. If varistor is not available, remove old varistor and leave it empty. Jumper positions, main transformer Mains Jumper 1 Jumper 2 Jumper 3 Varistor 100VAC A E F 221 120VAC A C D 221 220VAC B E - 391 / 441 240VAC

49、 B D - 391 / 441 PRO-SVR_LEGACY Page 14 of 14 Remote Interface Information The CA400 can be turned on or off using an simple interface connected to the Remote jack, located at the back of the unit. 040061r1.sch-1 - Thu Jul 26 15:57:04 2007 040062r1.sch-1 - Thu Jul 26 15:57:23 2007 040063r1.sch-1 - Thu Jul 26 15:57:47 2007 040065r1.sch-1 - Thu Jul 26 15:58:58 2007