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Power supply M500 carver

Fuse blow. checked bridge diode, capacitors. but question is how fuse keep blow?

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Re: power supply M500 carver

If you still need help on the Carver, try replacing the three terminal device "Triac" on the chassie on the power supply side.. Opening all of the collector connections on the output transistors will allow you to power the unit up without the major load on the power supply. Check the emitter base junctions with a analog meter on the X1 scale. You will generally get a half scale reading in one direction and an open circuit in the other. A good analog meter can be had at Lowes or probably Home Depot for about $20.00. I'll check back here in a few days. If you still need help, I'll set up an email address. I can describe the power supply circuit to you as well. The power supply is where the triac is used to control the output voltage to the output transistors.

Posted on Oct 14, 2008

Re: power supply M500 carver

I have the same problem. Worked fine then I sold it on eBay and the guy had the problem with it. I took the amp back. Let me know if you find anything out.

Posted on Feb 04, 2008

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Re: power supply M500 carver

Check the output transistors

Posted on Jan 11, 2008

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Carver r2000 keeps blowing fuse

Fuses blow when there's an overload. The most likely cause being a short-circuited semiconductor(s) located on the big heatsink. Other causes are a shorted device in the power supply section. Such as a rectifier or voltage control device.

Transistors tested with an ohm meter will show up as if you have touched the leads together when connecting across the terminals.

Oct 12, 2014 | Carver Amplifiers & Preamps

1 Answer

A small 2.5 amp fuse keeps blowing. It is located at the back of the unit just after the ac inlet

When a fuse blows suspect an overload in the power supply or power amp section.
For culprits in the power supply check the transformer, large capacitors, rectifier, voltage control semi-conductors, diodes.
In the amp section any semi-conductor on the heat-sink.

Semi-conductors - transistors and IC's are the biggest cause of fuse blowing. They become short-circuit acting like a piece of wire!
Because of this transistors and diodes are easy to spot with an Ohm Meter, as it will be like you have just touched the probes together.
Very often they have holes, or damage, or have burnt up with this kind of fault.
If it is a fault on the main amp section, check your speaker wiring as the + & - wires could have touched to cause it.

Apr 18, 2010 | Pioneer A509R Amplifier

1 Answer

Keeps blowing the fuse inside the unit.

When a fuse blows suspect an overload in either the power supply or main amp stage. The most likely cause is some part acting like a piece of wire instead of doing it's job. In the power supply it could be the transformer, voltage regulator, or the rectifier or any diode. In the amp section any semi-conductor on the heat sink.
Check first for burnt or damaged parts. If you have a multimeter any transistor or diode will quickly show up. For when you have the meter on the ohms setting and touch the terminals with the probes, it will show as if you had touched the probes together.

Apr 02, 2010 | ButtKicker BKA1000-4A Amplifier

1 Answer

Samick sga 120 amp keeps blowing fuses. replaced all rectifier diodes and tranformer seems to be working fine. any suggestions?

Fuse blowing is due to excessive current drain and the the first clue is the blown fuse itself. If the fuse blows with a flash a bang and splatters copper across the inside of the glass you have a hard blow caused by a dead short on the power supply, check for power switch flashing over internaly. Short circuit main filter capacitors. Shorted turns in power transformer primary winding. If fuse just separates check for short on output transistors C to E. Try isolating fault by disconnecting LT pos/neg supplies to output stage. Also check for partial shorts on speakers and speaker wires using an analog ohm meter on low ohms setting.

Mar 27, 2010 | Amplifiers & Preamps

2 Answers

Behringer super x pro.the fuse keeps blowing on the ac inlet(t200 MA).a replacement unit works fine in the system.

When a fuse keeps blowing suspect an overload in either the power supply section or main amp part.
Look for burnt or damaged parts first.
The suspects in the power section are: transformer, diodes, rectifier, voltage stablizer, regulator.
In the Amp Section anything on the heat sink.

Jan 12, 2010 | Amplifiers & Preamps

2 Answers

Pioneer power amp m-770 keeps blowing the 6.3 amp fuse what could be wrong?

Suspect an overload in the power supply or audio output stage.
Power supply culprits include transformer, the big capacitors, diodes, bridge rectifier, voltage regulator etc.
Audio culprits are anything on the heat sink(s).
Look for burnt, damaged parts too, anything running very hot!
Follow the circuit from the fuse see where it takes you too start.

Nov 05, 2009 | Pioneer Amplifiers & Preamps

1 Answer

Gemsound xp-550

A diode/rectifer or voltage stabliser, or leaky capacitor in the power supply.
Also the main transistors in the power amp or if it has an output IC - that!
If you can in anyway disconnect the power supply section from the amp circuit, you can isolate which part is faulty. For if it blows when disconnected from the power amp, you know it's just the power supply that's gone. And if it does not blow - then it's the amp!

Aug 24, 2009 | Gem Sound GemSound PA-585 2-Channel...

1 Answer

Carver M-1.5t amp. blows 15 amp fuse.

First didn't say if you are a tech or not. I'll make this really simple.

If you are not a seasoned tech with experience solving carver will waste tons of time and money guessing what the problem might be.

Carvers are quite the unique beast. They deliver whopping amounts of power in a small chassis. This is done by using a trick switching power supply. There can be any number of possible problems.

To properly diagnose this you will need an oscilloscope, signal generator, variac, and of course a really good quality multimeter that can test diodes and transistors.

IF and only IF you are a seasoned tech with all the above equipment, that has no experience repairing carver, then go online to ebay, find member techman777, and for around $15 you can get a nicely reprinted service manual. Troubleshooting expertise and the manual will take you foreward from there because the manual has a very thorough troubleshooting guide in it.

If you think you can fudge your way through the guide without any serious electronics knowledge, you are in for a rude shock as you will find that you are an earth man trying to read martian.

If you are just a casual fix it guy ( nothing wrong with that !!! ), I strongly suggest that you do NOT make this your first try at fixing an amp.

The value of these, in mint condition, all rebuilt is around $350- $450 on ebay all day long. if you are willing to invest that much, you can look up carver audio repair on google and send it off to them, as they are reported to do a nice job. can look me up on ebay, send it to me and I will do a nice job too, and that comes from 20+ years of repairing.

I know that this isn't much help, but carvers are very special, and require special knowledge to repair.

Best of luck.....Rob

Dec 15, 2008 | Carver Amplifiers & Preamps

1 Answer

No Power and Blown Fuse

This often indicates either a power supply problem or shorted output transistors. In either case, the unit will require replacement parts. If you have a multi-meter that can check diodes, check the rectifier diodes or bridge rectifier in the power supply first. If those are OK, next check the output transistors. If you don't have access to the meter, expect a parts cost in the $15-$25 range plus the local labor rate for the repair. This should not be a difficult repair for any shop that does audio repair.


Nov 12, 2008 | Sony STR-DE595 5-Channel Amplifier

1 Answer

Carver m500

Hi, first it's not power, it's the voltage you need to know, is the transformer burt, if not you can mesure the voltage output by putting a voltmeter at the primery to see if 120vac is there and then the output to see how mutch at each two wire at orange is and then at the two red is. They should be about 24vac on orage and 60 volts at the red.
Not shure what the voltage just guessing, if totaly dead then you have a burt transformer, some of these unit have a internal fuse, you may see them on the top, they may be also thermal shutdown sensor's fuse type, look to see if there is one, if so look at there value, thermal has a degree in C for the value and pico fuse has amp's or ex 4a .

I hope this help


Feb 07, 2008 | Yamaha DSPE390 Amplifier

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