my A52 died - could it be just a fuse?

**Peter Nielsen** · 29 October 2006, 12:13 Sunday

Originally posted by Eric242

My question is: Could it really be just a fuse and what would it take to replace it? Are there any specifics to take into consideration?

Eric, it sounds like it's the fuse. All you need is a standard phillips screwdriver. There is a fuse holder on the back panel of the A52.

When you replace the fuse, make sure to get a SLOW-BLOW type. If you replace it with a regular fast-blow, it may blow out immediately.

At 230V, the Halo A52 needs an 8 amp slow-blow (8AT) american style 1/4 x 1 1/4" fuse (6.3x32mm - NOT the euro 5x20mm).

Peter

**Eric242** · 29 October 2006, 16:08 Sunday

Hi Peter,

thanks for your advice! We have a religious holiday on wednesday on which I can spare some time for the amp. I will try to get such a fuse in the meantime and hopefully that´s it. I will get back with the results.

Eric

**Vince Helm** · 29 October 2006, 19:23 Sunday

Originally posted by Peter Nielsen

Eric, it sounds like it's the fuse. All you need is a standard phillips screwdriver. There is a fuse holder on the back panel of the A52.

When you replace the fuse, make sure to get a SLOW-BLOW type. If you replace it with a regular fast-blow, it may blow out immediately.

At 230V, the Halo A52 needs an 8 amp slow-blow (8AT) american style 1/4 x 1 1/4" fuse (6.3x32mm - NOT the euro 5x20mm).

Peter

Peter you rock!!!!!!

regards
Vince

**Eric242** · 01 November 2006, 07:12 Wednesday

Hi Peter and all!

I just opend up my a52 to take a look for the fuse(s). I did not find a fuse at the backpanel but it might be hidden where I couldn´t see properly.

I found 9 fuses and assume there is a tenth. The fuses are numbered, I found Fuse 1, 2, 5, 6, 8, 9, 10 and 11. No. 1, 2, 5, 6, 9 and 10 are easily visible on the top board. Beneath that board is another board that has Fuse No. 8, 11, ? (I assume it is No. 3 due to the design) and I assume it has another fuse (one to be opposite to No 11). Here is a picture with the fuses position.

The fuses are all euro type (5x20 mm) 6.3A slow blow. I guess the fuse I need to replace is a fuse that belongs to the amps power unit? I don´t think the fuses I found belong to it´s power unit and actually I don´t think they are blown. If I recall it correctly the small filament, thread or whatever you call that little thing within the fuse should be broken when the fuse is blown. And it seams to be all right within all fuses I found except for No. 11 where I can´t see that little thing.

Well, assuming the ? Fuse is No.3 and the assumed fuse next to No.3 is No.12, I would still have to find at least two fuses, No.4 and 7. Any idea if those missing fuses coud belong to the power unit and where they might be located?

Thanks in advance
Eric

**r100gs** · 01 November 2006, 08:50 Wednesday

The main fuse is located on the back panel. It's just above the AC plug. Its a black cap. http://www.parasound.com/img/halo/a52_rear_big.jpg

**Chris D** · 01 November 2006, 08:51 Wednesday

Wow, Eric, interesting picture! Me, I'd never open up an amp and tinker with it. Although I have a general engineering background, I just don't have enough knowledge to not screw it up. (general suggestion to others out there, too)

**Eric242** · 01 November 2006, 11:10 Wednesday

Originally posted by r100gs

The main fuse is located on the back panel. It's just above the AC plug. Its a black cap.

Ouch, stupid me. Sometimes the obvious things seam to be far to easy

Thanks for the "hint" r100gs!

Originally posted by Chris D

Me, I'd never open up an amp and tinker with it.

Well I wouldn´t do anything but open it up to have look how nice it is bulit

OK, if that fuse would have been inside the amp I would have replaced it, but thats all. Any additional screws are taboo under any circumstances!

Eric

**Peter Nielsen** · 01 November 2006, 20:07 Wednesday

Originally posted by r100gs

The main fuse is located on the back panel. It's just above the AC plug. Its a black cap. http://www.parasound.com/img/halo/a52_rear_big.jpg

Correct! You should find this fuse holder on your back panel:

A Phillips screwdriver is needed to unscrew the cap of the fuse holder and remove the fuse. In unscrews counterclockwise. Follow the direction of the arrow in the picture.

If you don't get the blue "Halo" light, it means that your low power standby circuitry is not working. (All Halo amps have a second transformer plus accociated circuitry for standby mode). AFAIK, the standby transformer does not have a user replacable fuse. Either the main fuse is blown, or the standby transformer or its circuitry is defective.

FWIW, the standby transformer is the yellow-white-silver component to the left of the FUSE_11 arrow in your picture. Any failed internal fuse would probably be on this circuit board. It seems like all the fuses you point to in the picture are on the main board. I'm pretty sure they will not affect standby operation in any way. Even if blown, you shold still have your blue Halo light and command of operation. Since your standby circuitry is dead, the fault is most likely limited to the main fuse, the standby board (where the little yellow transformer is located), or any connectors leading to this board following the connection from your 230V wall socket.

Peter

(P.S. To an EE the expression "black cap" means "black capacitor", so that's not a phrase I would use to point out a fuse holder :B )

Attached Files

**Peter Nielsen** · 01 November 2006, 20:55 Wednesday

Originally posted by Chris D

Me, I'd never open up an amp and tinker with it.

Hehehe... If I have A GOOD REASON to do so, I will :B

That said, I'm too old to open up a device just to look "what's inside" :W

Martin Logan just let me service my defective Decent myself! I got them to send me a new transformer free of charge. Excellent service! :T

Parasound also let me service my JC-1s myself! :T :T

I really hate when companies tell me that I have to send in my stuff for repair. (Which in the end always result in a new unit. If they actually service it, they will usually end up scratching or staining it, and I will demand a new unit :M Denial is futile, the Borg would say... )

Parasound always sent me new units, so I never had any issues with them :B

I really dislike the service (lack of swift action) that TacT is giving me. Brand new stuff. 2 amps of 5 functionally bad. 2 amps of 5 cosmetically bad. One pefect amp in 5. Much more expensive stuff, much more defective than Parasound, and the service is inversively slow compared to Parasound... I might be back to Parasound sooner than expected... :twisted:

Peter

**Eric242** · 02 November 2006, 12:49 Thursday

OK, it´s up and running again, just had to replace the 8A US style fuse as Peter said.

Thanks a lot Peter for your help and r100gs for opening the eyes of a blind

I still can´t beliefe I opened up my amp to search for the fuse that is more than visible on the back panel. Anyway, it is all fine again.

Thanks again
Eric

**Peter Nielsen** · 03 November 2006, 08:29 Friday

:banana: Glad to hear my diagnosis was correct :T

**marcus** · 10 December 2006, 09:51 Sunday

Just hoping it's a similar solution with my A51. . . .I will ask for a replacement + spare (just in case!) from CSE Solutions tomorrow. . . situation occured the unit was powered DOWN...then UP again quickly after. . . . .( :evil: dont ask!!!). . .When I removed the fuse it was properly blown (UP!) as in shattered to the extent I had to remove part of it with tweezers! (After disconnecting the power cable)

. . . IF my auto sensing power up function were more reliable I'd not have any need for people to touch my sexy power amp

**Peter Nielsen** · 10 December 2006, 11:28 Sunday

Originally posted by marcus

Just hoping it's a similar solution with my A51. . . .I will ask for a replacement + spare (just in case!) from CSE Solutions tomorrow. . . situation occured the unit was powered DOWN...then UP again quickly after. . . . .( :evil: dont ask!!!). . .When I removed the fuse it was properly blown (UP!) as in shattered to the extent I had to remove part of it with tweezers! (After disconnecting the power cable)

. . . IF my auto sensing power up function were more reliable I'd not have any need for people to touch my sexy power amp

Yep. This sounds 100% normal. A very quick power up-down-up may cause the toroidal transformer generate a huge current surge, which blows the fuse.

Everything should be back to normal once you replace the fuse.

Peter

my A52 died - could it be just a fuse?

my A52 died - could it be just a fuse?

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Related Topics