LEM-Procon1800P-pwr-sm 维修电路原理图.pdf

1 IndexSoldering point.Male connector.Female connector.M/F faston connector.Test point.Supply voltage.Logic supply ground.Analog supply ground.Chassis ground.Earth ground.Flag joined with one or more flagsGENERALMUSIC S.p.A. Sales Division: 47842 S.Giovanni in Marignano (RN) ITALY - Via delle Rose, 12Phone +39(0)541/959511 - Fax +39(0)541/957404 - Internet: Technical specifications, transistor packages, Procon 400p test procedures.2Procon 750p, Procon 1000p test procedures.3Procon 1250p, Procon 1500p test procedures.67Procon 750p schematic.8Procon 400p schematic.9Procon 1250p schematic.10Procon 1000p schematic.Procon 1500p schematic.11Procon 1800p schematic.12Procon 2200p schematic.13Spare part list.4Procon 1800p, Procon 2200p test procedures. 5with the same signal name inscribed.ATTENTIONObserve precautions when handling electrostatic sensitive devices. NoticeService must be carried out by qualified personnel only. Any tampering carried out by unqualified personnel during the guarantee periodwill forfeit the right to guarantee.For a correct operation of the instrument, after having switched off, be careful to wait at least 3 seconds before switching on again.To improve the devices specifications, the schematic diagrams may be subject to change without prior notice.All components marked by this symbol have special safety characteristics, when replacing any of these components use onlymanufacturers specified parts. The () micro symbol of capacitance value is substituted by U.The () omega symbol of resistance value is substituted by E. The electrolytic capacitors are 25Vdc rated voltage unless otherwise specified.All resistors are 1/8W unless otherwise specified.All switches shown in the OFF position. All DC voltages measured to ground with a voltmeter 20KOhm/V.service manualschematic diagramsCODE: 270312Power Amplifiersprocon plusRadioFans.CN 收音机爱 好者资料库2PROCON400p - Test proceduresPRECAUTION To prevent short circuit during any test, the oscilloscope must be EARTH INSULATED, this occurs because some test require to connect its probe to the amplifi er output, non-compliance may cause damages to oscilloscope inputs circuitry. Before removing or installing any modules and connectors, disconnect the amplifi er from AC MAINS and measure the DC supply voltages across each of the power supply capacitors. If your measurement on any of the caps is greater than 10Vdc, connect a 100E 60W resistor across the applicable caps to discharge them for your safety. Remember to remove the discharge resistor immediately after discharging caps. Do not power up the amplifi er with the discharge resistor connected. Do not check the amplifi er with the speakers connected use the appropriate load resistors only. BE CAREFUL increasing the Variac you must not exceed the nominal mains voltage plus its tolerance (see specifi cations) any upper volt-age can be cause of damage.VISUAL CHECK Use compressed air to clear dust in the amplifi er chassis. Before proceed to supply the amplifi er check visually the internal assembly, if appears an evident damage fi nd the most possible rea-sons that cause it. Check the wiring cables for possible interruptions or shorts. If the damage has burnt a printed circuit board dont try to repair it, replace with a new one.TESTING GEAR Audio Generator Dual Trace Oscilloscope Digital Multimeter 4E 300W, 8E 450W, 100E 60W resistors Variac Digital Thermometer (not indispensable)SETUP Connect the Variac between the Mains and the amplifi er and set it at zero voltage. Turn full counter-clockwise the LEVEL potentiometers. Connect the audio generator to the channel inputs and set it to 1KHz 775mVrms (0dBu) sinusoidal signal. Connect the two scope traces to the amplifi er outputs, before the relay, and set them in DC at 20V/div. 2mS/div.SUPPLY CHECK Verify with the Multimeter the insulation between the heatsinks and all transistor collectors mounted on them; placing the multimeter tips between the screw heads and the collector pins you can exclude an erroneus reading due to the insulation of the heatsink anodization. Verify with the Multimeter the NTC (RT1) and R1 paralleled resistor value, it must be about 1080ohm (at 25c). Disconnect the amplifi er module supplies of each channel (red and yellow wires). Set the Variac to the nominal mains voltage, turn on the Amplifi er, then check with the Multimeter the AC supply voltages: F1-F2 = 292Vac. RED secondary wires = 879Vac. Re-set the Variac at zero voltage, turn off the amplifi er and recon-nect the supplies at each amplifi er module. Set up the Variac slowly monitoring the oscilloscope screen, it should display no signal; if you notice a DC voltage or a protection trips check the amplifi er as suggested in the ADVICES. As soon as the +12VF supply circuit reaches its nominal value, all cooling fans run at their minimum and the speaker output relais (J201-202) switch. When the Variac ac voltage reaches the nominal voltage verify the DC supplies as follow: +VCC = +596Vdc -VCC = -596Vdc U101 pin 8 = +120.5Vdc U101 pin 4 = -120.5Vdc U403 pin 3 = +120.5Vdc If one or more voltages dont correspond, check the rectifi ers, ca-pacitors and transformers disconnecting them from cir cuit ry.CHANNEL CHECK Be sure you have dis con nect ed the load re sis tor. Increasing the input sig nal also the output signal raise ac cord ing ly, it must be sym met -ri cal without vis i ble dis tor tion or os cil la tion as shown in figure (note: the fi g ure is rep re sent a tive dont re fer to the levels dis played). If there is a dis tor tion read the sec tion ADVICES. When the input sig- nal exceeds -20dBu (20Vpp on output) the fans turn at their max i mum speed. Firstly you must check the channel without load, after-wards you must repeat the check with the loads attached, the following table reports the approx. maximum level obtainable with this amp: out level in level no load 113Vpp +1.5dBu 1CH 4E 91Vpp -0.2dBu 2CH 4E 82Vpp -2.0dBu Bridge 8E 161Vpp -2.3dBuLEVEL METER ADJUSTMENT Check if the clip led lights at -2dBu on input (80Vpp on output), if necessary adjust the trimmers W301/2 on dis play board.OFFSET ADJUSTMENT Set the input level at minimum (no signal), the output dc offset voltage must be within range 20mV, if necessary adjust the VR201 trimmer (for each channel) to be within this range.BIAS ADJUSTMENT No bias adjustment is necessary for this amplifi er circuitry.ADVICES If you have determinate that the problem is a short on a rail, you must check the output transistors. To determine which transistor devices are bad, use a soldering iron to lift one leg of each emitter pin and measure the resistance across emitter and collector of each device. Unsolder and lift one leg of each base pin and check the base-collector resistance. Replace any device that measure as a short. If all the transistors are OK, unsolder and lift one leg of each diode and check them. Check the circuit board for open foil traces. Use the Multimeter to check the resistors, particularly the base and emitter resistors of damaged transistor. If the input sinewave appears to be distorted during the negative cycle, you can assume that the problem is located somewhere in the circuitry of the positive rail. If the positive cycle appears distorted, you can assume that the problem is in the circuitry of the negative rail. The dc voltages printed on the schematics are measured with the amplifi er in steady state without input signal and nominal mains volt-age supply, it can be useful to localize a damage.POWER SPECIFICATIONS400P750P1000P1250P1500P1800P2200PEIA output power 1kHz, THD maximum 1%Both channels8 ohm4 ohm8 ohm BRIDGED125+125200+200400215+215375+375750300+300550+5501100375+375625+6251250450+450750+7501500550+550900+9001800650+6501100+11002200ELECTRICAL SPECIFICATIONS400P750P1000P1250P1500P1800P2200PINPUT SENSITIVITYINPUT IMPEDANCEFREQUENCY RESPONSEVOLTAGE GAIN32dB33dB35dB36dB37dB37dB39dBSLEW RATEDAMPING FACTORCROSSTALKS/N ratioHarmonic distortion THDIntermodulation distortion SMPTEGENERAL SPECIFICATIONS400P750P1000P1250P1500P1800P2200PPROTECTIONSCONTROLSINDICATORSCONNECTORSINOUTPOWER SUPPLYDIMENSIONSmm (WxHxD)WEIGHTkg13151819.52123.525PROCON PLUS SERIES TECHNICAL SPECIFICATIONS0dB (0.775V)10 kOhms (balanced)1050000 Hz (-0.5dB)22 V/ms400:1 1kHz, 8Ohms-82 dB (1KHz)Power transformer thermal protectionShort circuit protectionSensor for current on outputsCLIP Limiter on each channelSoft-start circuit (1000P to 2200P)-100 dB483x88x4560.1% (ref 20Hz -20KHz)0.1% (SMPTE method, 60Hz & 7kHz, 4:1 ratio)1 XLR-F + 1 JACK in parallel for each channel2 x BINDING POST + 1 SPEAKON for each channel (400-1500) 1 SPEAKON for each channel + 1 SPEAKON for BRIDGE output (1800-2200)483x88x366483x88x428ON/OFF switch21-detect input level control for each channelMODE selectorSHIELD selectorPOWER ON: 1 red LEDBRIDGE: 1 red LEDPROTECT: 1 red LEDLEVEL: 2 x 5-LED metersLIMIT: 1 red LEDsee label on the unitRadioFans.CN 收音机爱 好者资料库3 PROCON750p - Test proceduresPRECAUTION To prevent short circuit during any test, the oscilloscope must be EARTH INSULATED, this occurs because some test require to connect its probe to the amplifi er output, non-compliance may cause damages to oscilloscope inputs circuitry. Before removing or installing any modules and connectors, disconnect the amplifi er from AC MAINS and measure the DC supply voltages across each of the power supply capacitors. If your measurement on any of the caps is greater than 10Vdc, connect a 100E 70W resistor across the applicable caps to discharge them for your safety. Remember to remove the discharge resistor immediately after discharging caps. Do not power up the amplifi er with the discharge resistor connected. Do not check the amplifi er with the speakers connected use the appropriate load resistors only. BE CAREFUL increasing the Variac you must not exceed the nominal mains voltage plus its tolerance (see specifi cations) any upper volt-age can be cause of damage.VISUAL CHECK Use compressed air to clear dust in the amplifi er chassis. Before proceed to supply the amplifi er check visually the internal assembly, if appears an evident damage fi nd the most possible rea-sons that cause it. Check the wiring cables for possible interruptions or shorts. If the damage has burnt a printed circuit board dont try to repair it, replace with a new one.TESTING GEAR Audio Generator Dual Trace Oscilloscope Digital Multimeter 4E 450W, 8E 800W, 100E 70W resistors Variac Digital Thermometer (not indispensable)SETUP Connect the Variac between the Mains and the amplifi er and set it at zero voltage. Turn full counter-clockwise the LEVEL potentiometers. Connect the audio generator to the channel inputs and set it to 1KHz 775mVrms (0dBu) sinusoidal signal. Connect the two scope traces to the amplifi er outputs, before the relay, and set them in DC at 20V/div. 2mS/div.SUPPLY CHECK Verify with the Multimeter the insulation between the heatsinks and all transistor collectors mounted on them; placing the multimeter tips between the screw heads and the collector pins you can exclude an erroneus reading due to the insulation of the heatsink anodization. Verify with the Multimeter the NTC (RT1) and R1 paralleled resistor value, it must be about 1080ohm (at 25c). Disconnect the amplifi er module supplies of each channel (red and yellow wires). Set the Variac to the nominal mains voltage, turn on the Amplifi er, then check with the Multimeter the AC supply voltages: F1-F2 = 292Vac. RED secondary wires = 10610Vac. Re-set the Variac at zero voltage, turn off the amplifi er and recon-nect the supplies at each amplifi er module. Set up the Variac slowly monitoring the oscilloscope screen, it should display no signal; if you notice a DC voltage or a protection trips check the amplifi er as suggested in the ADVICES. As soon as the +12VF supply circuit reaches its nominal value, all cooling fans run at their minimum and the speaker output relais (J201-202) switch. When the Variac ac voltage reaches the nominal voltage verify the DC supplies as follow: +VCC = +727Vdc -VCC = -727Vdc U101 pin 8 = +120.5Vdc U101 pin 4 = -120.5Vdc U403 pin 3 = +120.5Vdc If one or more voltages dont correspond, check the rectifi ers, ca-pacitors and transformers disconnecting them from cir cuit ry.CHANNEL CHECK Be sure you have dis con nect ed the load re sis tor. Increasing the input sig nal also the output signal raise ac cord ing ly, it must be sym met -ri cal without vis i ble dis tor tion or os cil la tion as shown in figure (note: the fi g ure is rep re sent a tive dont re fer to the levels dis played). If there is a dis tor tion read the sec tion ADVICES. When the input sig- nal exceeds -20dBu (20Vpp on output) the fans turn at their max i mum speed. Firstly you must check the channel without load, after-wards you must repeat the check with the loads attached, the following table reports the approx. maximum level obtainable with this amp: out level in level no load 139Vpp +3.0dBu 1CH 4E 117Vpp +1.5dBu 2CH 4E 109Vpp +0.9dBu Bridge 8E 214Vpp +0.7dBuLEVEL METER ADJUSTMENT Check if the clip led lights at -1dBu on input (90Vpp on output), if necessary adjust the trimmers W301/2 on dis play board.OFFSET ADJUSTMENT Set the input level at minimum (no signal), the output dc offset voltage must be within range 20mV, if necessary adjust the VR201 trimmer (for each channel) to be within this range.BIAS ADJUSTMENT No bias adjustment is necessary for this amplifi er circuitry.ADVICES If you have determinate that the problem is a short on a rail, you must check the output transistors. To determine which transistor devices are bad, use a soldering iron to lift one leg of each emitter pin and measure the resistance across emitter and collector of each device. Unsolder and lift one leg of each base pin and check the base-collector resistance. Replace any device that measure as a short. If all the transistors are OK, unsolder and lift one leg of each diode and check them. Check the circuit board for open foil traces. Use the Multimeter to check the resistors, particularly the base and emitter resistors of damaged transistor. If the input sinewave appears to be distorted during the negative cycle, you can assume that the problem is located somewhere in the circuitry of the positive rail. If the positive cycle appears distorted, you can assume that the problem is in the circuitry of the negative rail. The dc voltages printed on the schematics are measured with the amplifi er in steady state without input signal and nominal mains volt-age supply, it can be useful to localize a damage.PROCON1000p - Test proceduresPRECAUTION To prevent short circuit during any test, the oscilloscope must be EARTH INSULATED, this occurs because some test require to connect its probe to the amplifi er output, non-compliance may cause damages to oscilloscope inputs circuitry. Before removing or installing any modules and connectors, disconnect the amplifi er from AC MAINS and measure the