QSC-RMXseriesC-pwr-sm维修电路原理图.pdf

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1、Technical Service Manual RMX Series 2RU models RMX 850 RMX 1450 RMX 1850HD RMX 2450 *TD-000098-00* TD-000098-00 Rev. C QSC Audio Products, LLC Costa Mesa, CA 92626 USA RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RMX Series Technical Service Manual (2RU models)1 TD-000098-00 rev. C QSC Audio Prod

2、ucts, LLC Technical Services Group Phone:1-800 QSC AUDIO (1-800-772-2834) USA only +1 (714) 957-7150 Fax:+1 (714) 754-6173 Postal:1665 MacArthur Blvd. Costa Mesa, California 92626 USA E-mail:tech_ Web: (product information and support) (parts and accessory sales) RMX 850 RMX 1450 RMX 1850HD RMX 2450

3、 RMX Series Technical Service Manual Copyright 2001, 2002, 2005, 2008 QSC Audio Products, LLC All rights reserved. Document # TD-000098-00, Rev. C. Released June 2008. RadioFans.CN 收音机爱 好者资料库 2QSC Audio Products, LLC RMX 850RMX 1450RMX 1850HDRMX 2450 OUTPUT POWER in watts FTC: 20 Hz20 kHz 0.1% THD,

4、both channels driven 8 per channel185260350450 4 per channel280400550650 EIA: 1 kHz 0.1% THD, both channels driven 8 per channel200280360500 4 per channel300450600750 1 kHz 1% THD, typical, both channels driven 2 per channel4307009001200 Bridge Mono: 8, 20 Hz20 kHz, 0.1% THD5308001300 8, 1 kHz, 0.1%

5、 THD60090012001500 4, 1 kHz, 1% THD, typical830140018002400 DYNAMIC HEADROOM2 dB 4 DISTORTION SMPTE-IM 0.01% 0.01% 0.02% 300 8 NOISE (unweighted 20 Hz to 20 kHz, below rated output)100 dB100 dB100 dB100 dB VOLTAGE GAIN31.6 (30 dB)40 (32 dB)46 (33 dB)50 (34 dB) INPUT SENSITIVITY, V RMS full rated pow

6、er 81.15v (+3.4 dBu)1.15v (+3.4 dBu)1.16v (+3.5 dBu)1.23v (+4.0 dBu) INPUT IMPEDANCE10 k unbalanced 20 k balanced CONTROLSFront: AC switch, Ch. 1 and Ch. 2 gain Rear: 10-position DIP switch INDICATORSPOWER:Green LEDCLIP:Red LED, 1 per channel SIGNAL:Yellow LED, 1 per channel CONNECTORSInput:Active b

7、alanced; XLR and (6.3 mm) TRS, tip and pin 2 positive, and barrier strip Output:“Touch-Proof” binding posts and Neutrik Speakon COOLINGContinuously variable speed fan, back-to-front air flow AMPLIFIER PROTECTIONFull short circuit, open circuit, thermal, ultrasonic, and RF protection Stable into reac

8、tive or mismatched loads LOAD PROTECTIONTurn-on/turn-off muting (all models) AC couplingAC couplingTriac crowbar (each channel)Triac crowbar (each channel) OUTPUT CIRCUIT TYPEABABHH AB: Class AB+B complementary linear output H: Class AB+B complementary linear output with Class H 2-step high efficien

9、cy circuit DIMENSIONS19.0 (48.3 cm) wide, 3.5 (8.9 cm) tall (2 rack spaces) 15.9 (40 cm) deep (rack mounting to rear support ears) WEIGHTShipping:41 lb. (18.6 kg)46 lb. (20.9 kg)50.5 lb. (23 kg)50.5 lb. (23 kg) Net:35 lb. (15.9 kg)40 lb. (18.2 kg)44.5 lb. (20.2 kg)44.5 lb. (20.2 kg) POWER REQUIREMEN

10、TSAvailable for 120 or 220240 VAC, 50/60 Hz POWER CONSUMPTION 120 VAC (both channels driven) Multiply currents by 0.5 for 230V units l ac i pyT 1 l l uF 2 xaM 3 e l d IA5 . 0 8 A3A1 . 4A4 . 7 4 A5 . 4A6 . 6A5 . 11 2 A5 . 6*A5 . 9*A71 l ac i pyT 1 l l uF 2 xaM 3 e l d IA5 . 0 8 A7 . 3A4 . 5A01 4 A6A6

11、 . 9A61 2 A3 . 9*A7 . 41*A52 l ac i pyT 1 l l uF 2 xaM 3 e l d IA6 . 0 8 A4A7 . 9A4 . 61 4 A3 . 6A6 . 51A72 2 A2 . 9*A32*A14 RMX Series Performance Specifications Typical 1 Full 2 Max 3 Idle0.8 A 8 3.9 A6.9 A12.6 A 4 6.1 A11.2 A20.7 A 2 8.7 A16.6 A*32 A* 1. TypicalMeasured with pink noise signal on

12、all channels at 1/8 of full average power. Producing peaks that occasionally reach the amps clipping point, this level approximates the maximum operating level before clipping affects sound quality. These data would be the amps typical worst-case current. 2. FullMeasured with pink noise signal on al

13、l channels at 1/3 of full average power. Music at this level would typically produce massive clipping. In a class B amplifier, this would be the approximate point of maximum heat production. 3. MaxMeasured with continuous sine wave signal on all channels at a point of slight clipping (1% THD). This

14、represents a “test bench” scenario and does not resemble any real-world usage. US patents pendingSPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE RadioFans.CN 收音机爱 好者资料库 RMX Series Technical Service Manual (2RU models)3 TD-000098-00 rev. C Table of Contents RMX Series Performance Specifications. 2 1.

15、 Introduction . 5 1.1 Restriction of Hazardous Substances Directive (RoHS). 5 1.2 QSC serial numbers . 5 1.3 Service bulletins. 5 1.4 The well-equipped service bench. 6 1.5 Working with surface-mount components . 6 1.6 Series description . 8 1.7 Technical descriptions and theory of operation . 8 2.

16、Component identification and pinout . 11 3. Troubleshooting: Symptoms, causes, the last five digits are the sequential identifying number for each individual amplifier. For example, a serial number of 0807xxxxx would indicate that the amplifier was built in 08/2007, or August 2007. The date code is

17、important for determining whether an amplifier is subject to a service bulletin, covered by a warranty (in the absence of original purchase records), etc. The amplifiers serial number can be found on a label on the rear panel. The label also indicates the model number, power rating, 4 current draw,

18、and the AC mains voltage the amplifier was made for. Certain design changes that the RMX amplifiers have undergone commenced with a particular date code; for example, the RMX amplifiers with a date code of 0406 or later conform to the European Unions RoHS Directive and must be serviced only with lea

19、d-free solder and soldering irons that are not contami- nated with lead or other heavy metals covered by the directive. 1.1 Restriction of Hazardous Substances Directive (RoHS) Since April 2006, all RMX Series amplifiers are manufactured to conform to the European Unions RoHS Directive, which reduce

20、s the amount of hazardous substances allowed in products for sale within its member nations. In electronic equipment such as audio power amplifiers, this applies primarily to certain toxic heavy metals, such as lead, which may be present in electronic components, solder, and other parts. RoHS-compli

21、ant materials When servicing RoHS-compliant amplifiers, it is important for the service technician to use only RoHS-compliant components and solder (lead-free). All replacement parts provided by QSC for RoHS-compliant products are certified as RoHS compliant. RoHS-compliant tools Soldering irons and

22、 desoldering apparatus used on RoHS-compliant products must also not be contaminated by hazardous substances, such as lead. Therefore, you cannot use the same soldering and desoldering tools for RoHS-compliant products and solder as you do for non-compliant products and solder. You must either use s

23、eparate soldering irons, desoldering tools and braid, etc., or at the very least designate separate tips and braids and use only the appropriate ones. If you contaminate a tip or braid, even inadvertently, by using it on a non-compliant product or solder, you should no longer use it with RoHS-compli

24、ant products or solder. 1.3 Service bulletins Contact QSC Technical Services to make sure you have the most up-to-date service bulletins for RMX Series amplifiers. Service bulletins may be distributed in hard copy, via fax, and electronically (Adobe Acrobat PDF) via CD-ROMs, FTP from the QSC web sit

25、e (), and e-mail. These service bulletins had been issued at the time this manual was printed: RMX0001, “Q205 Lead Stress” (RMX2450 only) RMX0002, “RMX Turn-on Delay” (all RMX models) RMX0003, “RMX2450 Turn-off Mute” (RMX2450) RMX0004, “RMX2450 AC Wire Routing” (RMX 2450) RMX0005, “RMX2450 AC Wire R

26、eplacement” (RMX2450) RMX0006, “RMX2450 IRFZ44N Field Effect Transistors (RMX2450) Figure 1.1. The label displays two vital pieces of information: the amplifiers serial number and operating voltage RadioFans.CN 收音机爱 好者资料库 6QSC Audio Products, LLC Solder 1.4 The well-equipped service bench To properl

27、y service RMX amplifiers, a technician needs the right tools. The technicians service bench should have the following equipment: Digital multimeter with RMS AC voltage and current Digital clamp-on ammeter Dual-trace oscilloscope Audio distortion analyzer Non-inductive load resistors, configurable as

28、 8 ohms (min. 500 watts capacity), as 4 ohms (min. 750 watts capacity), and 2 ohms (min. 1200 watts capacity); see Figure 1.2 and Table 1.1. Variable AC voltage source, such as a Variac or Powerstat variable trans- former, with a rated current capacity of up to 25A (for 120V models) or 12A (for 230V

29、 models) Low-distortion audio sine wave generator Philips and flat screwdrivers Soldering iron with a fine tip, 2560W recommended (if you service both RoHS-compliant and non-compliant amplifiers, you will need separate soldering and desoldering equipment for each) Appropriate rosin-core solder (use

30、only RoHS compliant lead- free solder for RoHS-compliant amplifers; for non-RoHS amplifiers, use a 60/40 or 63/37 Pb/Sn alloy) Long-nose pliers Diagonal cutters Wire strippers Automated test equipment, such as an Audio Precision workstation, is very useful for servicing RMX amplifiers. Contact QSC T

31、echnical Services to obtain applicable AP test files. Solder braid 1.5 Working with surface-mount components RMX amplifiers, like many modern electronic products, use surface-mount technology (SMT) components where appropriate in order to make high-density circuitry that is reliable and economical t

32、o manufacture. SMT components in the RMX amps are used in the small-signal and control circuits, so they do not handle significant amounts of power; therefore, they are subject to very little stress and should seldom fail. Sometimes they do fail, or they require replacement for a performance upgrade

33、 or modification. Thus, it is important to know how to work with SMT components. Specialized tools and equipment exist for soldering, unsoldering, and removing SMT components quickly and efficiently, but they are often expensive. Most SMT repairs, though, can be handled reasonably well with common t

34、ools and equipment, such as tweezers, solder braid, and fine-tip soldering irons. The original factory components are tacked to the board with a spot of glue, so you might have to apply some force to break the adhesive. Two-terminal components (resistors, capacitors, diodes, etc.) Removal 1 Use two

35、soldering irons, preferably about 25 to 40 watts, with fine tips. 2 With a soldering iron in each hand, hold one tip on the solder at one end of the component and the other tip on the other end (Figure 1.3). 3 Once the solder melts on both ends, grip the component between the two tips and lift it fr

36、om the circuit board. 4 Use solder braid and a soldering iron to remove the solder from the two pads (Figure 1.4). Figure 1.2. Load resistor bank Table 1.1. Load resistor bank switch truth table SW1SW2SW3 SW4 8888 R1: 8 , 500W non-inductive R2R4: 8 , 300W min. non-inductive R1R2R3R4 SW1SW2SW3SW4 (no

37、 load)OFF 8 ONOFFOFFOFF 4 ONONOFFOFF 2 ONONONOFF 0 (short circuit)ONON Figure 1.5. Figure 1.3. Figure 1.4. RadioFans.CN 收音机爱 好者资料库 RMX Series Technical Service Manual (2RU models)7 TD-000098-00 rev. C Solder Tweezers Solder Insertion 1 With a soldering iron and appropriate solder, melt just enough s

38、older onto one pad to create a small mound (Figure 1.5). 2 Grasp the component in the middle with tweezers. Melt the small mound of solder with the iron and place the component across the two pads (in the correct orientation, if the component is sensitive to direction) and press it flat against the

39、circuit board, with one end of the component immersed in the melted solder (Figure 1.6). 3 Hold the component in place and take the soldering iron away. Let the solder harden to tack the component in place. 4 Fully solder the other end of the component to its pad. Let the solder harden (Figure 1.7).

40、 5 Fully solder the tacked end of the component to its pad (Figure 1.8). 3 When the solder on both ends melts, grip the component between the two tips and lift it from the circuit board. You might need to quickly touch the pad on the middle terminal with a soldering iron to melt any remaining solder

41、 that might be holding the component down. 4 Use solder braid and a soldering iron to remove the solder from the three pads. Insertion 1 With a soldering iron and appropriate solder, melt just enough solder onto one pad to create a small mound of solder. 2 Grasp the component with tweezers. Melt the

42、 small mound of solder with the iron and place the component in the correct orientation across the three pads and press it flat against the circuit board, with one terminal of the component pressed into the melted solder. 3 Hold the component in place and take the soldering iron away. Let the solder

43、 harden to tack the component in place. 4 Fully solder the other terminals of the component to their pads. Let the solder harden. 5 Fully solder the tacked terminal of the component to its pad. Multi-pin components (ICs, etc.) Removal Removing a multi-pin SMT component is a delicate procedure. Ideal

44、ly, you should use a soldering iron with an attachment that allows you to heat all the pins simultaneously. If such a soldering device is not available, use this procedure: 1 Use a soldering iron and solder braid to remove as much solder as possible from the pins of the component. 2 With fine tweezers, carefully try to lift each pin to see if its free. If its not, touch it with the tip of the solderi