Amp Shutting Down, need help

I have a Cary 7.250 brand new amp that shuts down after 20 seconds in my NYC apartment. I have sent the unit back to Cary where it tests fine. I have tried the unit at my friend’s apartment and his place of work and it works fine. The unit is 100% in working order. After talking to many people I was told to attach a 50' extension cord and low and behold it worked.

The good news is that I have a dedicated 20amp circuit to this outlet. My voltage reads 118 volts and Cary said that is not a problem as the unit will work between 90 and 130 volts. I have tested for voltage on the negative lead to ground and there is no stray voltage. I have also tried the unit on other outlets in the apartment and the same problem occurs.

My mono blocks and all other components work just fine. So I’d love to hear suggestions as to how to get rid of this 50’ extension cord?

Thanks in advance.
Sounds like a plan to me, except that my instinct would be to avoid configurations in which the Brick Wall and the Power Cell are used in series. If you are using both, have them both plugged directly into the wall.

Also, given the small difference in price between the two versions of the Brick Wall, I think it would make sense to get the 8-outlet version. That would give you the flexibility to experiment with what gets powered from where.

-- Al
Sailcappy, I am really sold on the idea that the breaker is at fault. Have you been using it as a power switch? Or is the amplifier designed with it being the power switch?

Either way what I would do is replace the breaker... troubleshooting from a distance is always tricky, but we can be very sure that the solution has to do with the inrush current on the power transformers.
08-24-12: Atmasphere
"Sailcappy, I am really sold on the idea that the breaker is at fault. Have you been using it as a power switch? Or is the amplifier designed with it being the power switch?"

Based on the mag-breaker's rear location, the amp's remote-trigger feature, and front-actuated Power/Standby pushbutton switch, it's intended as an "actuate-and-leave it" protection device. Although, with all his troubleshooting prior to and well after Cary's diagnostic testing, that particular mag-breaker has probably been subjected to several dozens of set/trip cycles. Certain internal electro-mechanical aspects could be deteriorating, though lacking the component's specs/data information, and additional dianostic measurements, it's an educated assertion - something most experienced techs would investigate in any applicable field of electronics.

If the two filter options fail to resolve your issue, I wonder if Cary would sell you a replacement breaker. Is your skillset up to changing that component (which *should* be a breeze), or maybe your friend could do it rather than sending the amp back? Even if Cary won't sell you one, the component's mfr info/PN is probably still available on the breaker's body once it's accessed within the amp (possibly by removing the bottom panel) - thus likely availability unless a custom-spec'd option.

When the problem first occurred Cary sent me a new circuit breaker which is the ON/OFF power switch. I installed it which was easy to do. The problem is not with the breaker being defective. Remember it works fine at Ken's place of work.

My updated plan is to:
1. Try the DC Blocker if that does not work....
2. Try the Brick Wall if that works I will replace the SR Powercell with the Brick Wall.
3. If the Brick Wall does not work then I am at a loss.
08-15-12: Sailcappy
I have had it replaced to no avail.

I *thought* I'd read someone mentioning the breaker was replaced, but couldn't confirm yesterday when quickly going back through the posts, so I wasn't 100% sure and am entertaining Ralph's (Atmasphere) concern considering the breaker's accumulative set/trip cycles, *if* it was still the original. Also, based on first-hand experiences, have had to replace numerous "new" components after immediate or delayed faulty operation, especially regarding a device unintended for elevated repetitive mechanical cycling.

Regarding the amp working at other locations (which I've always taken into consideration), Ralph posted some scenario possibilities that may allow a deteriorating breaker to continue functioning, and I agree is possible. Lacking any witness confirmation, or actually being there to assure apple-to-apple testing/comparisons, all we can do is speculate. He is quite knowledgeable, as with Al and Jim. We all come from decades of professional backgrounds in various electronics fields and offer legitimate suggestions based on scenarios and probabilities we've encountered over the years. All of us would *prefer* to be there - armed with appropriate test equipment - able to make better determinations. That's what I do for a living. So, lacking factual data, all one can do is suggest trying different things with hopes of resolvement.

Your updated plan is fine if unwilling to wait for Ken to return and 'scope your AC (the best *practical* option to minimize guessing). If the two devices fail to resolve, either keep or sell them, and take my joking recommendation to neatly coil-stack an appropriately rated ext cord and hide it out of sight behind other equipment, rack/furniture, etc., or package it cosmetically. You're planning to power the Cary from the conditioner, so, will *all* of the electronics be accumulated in one location near the 20 amp outlet? ...On a vertical rack, shelves, table-top, etc. - thus able to hide a majority of a coiled flat or stacked (black) ext cord?

If the Brick Wall works, it's not very WAF either, so how would you address that vs. a "shaped" ext cord, if the BW doesn't work. I can't envision a scenario where the cord couldn't be hidden or repackaged cosmetically, even if the amp is remoted across the room. It still requires a cord that has to plugged *somewhere*, and you plan to feed it from the SR conditioner. Describe your equipment layout if otherwise.

Again, if we *knew* exactly what was wrong (if anything) with your AC, if not equipment related, could better diagnose and recommend specific cures.