Is my amp dead for good?

[Old Garage-Bander]

400 volts! That’s crazy

Maybe not so crazy.
If Kenya is on something like a 220 volt grid vs our 115-ish, they are already a lot closer to 400 to start with.
And the 400 volts really needs an asterisk because we don't know tha nature of that 400 volts.
Was it a bunch of spikes/surges, or continuous?
Still crazy that it got high enough to blow up his amp.

 

[Killed_by_Death]

What places are those?

I'm not going to list them out here & risk offending someone from one of those countries, but OTOH they'd probably confirm that I'm right
Expats get discriminated against often, it's just a fact of life some places.

 

[byacey]

OK then.
Please be sure to heed the advise that Agedhorse gave you.
Eye protection at the very least is also advised when first powering it up.

Good luck.
Let us know how it goes.

At the very least, power it up with a 60W lightbulb in series with the AC power. This may well prevent further catastrophic results from not checking all the usual suspects in the front end circuitry. Because the thermistor is cooked, I would firstly be checking the input bridge rectifier and filter cap(s), and possibly the switching transistor. Often such a thermistor would be used as an inrush current limiter. Because this thermistor is cooked, I can pretty much guarantee there are other components that have failed too.

This probably is all beyond the ability of the original poster, but he might take this info to a local tech to help things along.

 

[Old Garage-Bander]

What places are those?

Kenyan forums have multiple reports of people getting compensation from the power company by submitting proof of repair costs for voltage surges.

If I lived at risk of same I’d probably be investing in power conditioning equipment.

B>

You think you aren't at risk?
A nice solar flare or an otherwise large EMP, and it all goes dark for a veeeery long time.
Or something more simple and local like a high voltage line getting crossed up with your incoming service.

 

[Kevin1960]

This is why I used to just flip off our main breaker when the local power distributor had brownouts.
We'd do w/o power until we saw that the other homes were doing fine & then finally power back up.

At the time I had this handy little battery-powered fan + light, so it could keep you cool & light up the room at the same time.

My Dad was an electrician for 35 years and I do remember him telling me that the gap inside a breaker between the contacts is not a great way to isolate you from large current fluctuations on the grid and the best insurance was the distance of total disconnection. The further the better. Just a constructive thought, I hope.

 

[Killed_by_Death]

I should have been more clear. In Thailand our main "breaker" was a Frankenstein switch:

 

[Kevin1960]

I should have been more clear. In Thailand our main "breaker" was a Frankenstein switch:

View attachment 2867048

I like this a lot. I wish we all had one of these at the meter.

 

[Signalsdrone]

My Dad was an electrician for 35 years and I do remember him telling me that the gap inside a breaker between the contacts is not a great way to isolate you from large current fluctuations on the grid and the best insurance was the distance of total disconnection. The further the better. Just a constructive thought, I hope.

That's why at the railway, we still use old mechanical relays with big air gaps for some critical applications. Electronics can become unreliable and sometimes dangerous if they fail due to surges and voltage spikes.

 

[packrat]

I'm not going to list them out here & risk offending someone from one of those countries, but OTOH they'd probably confirm that I'm right
Expats get discriminated against often, it's just a fact of life some places.

Sure. A lot of countries have a large amount of anti-immigrant sentiment. In this case you're assigning the ill-will against people who are rich, but it's much more likely that that fault-finding way against those people with fewer connections, a situation expats are almost always in.

B>

 

[Killed_by_Death]

I've witnessed it many places, two-tier (and sometimes three-tier) pricing & it's usually just because the expat has more money, or at least that is what they assume.

When I had a guy hit & run my new vehicle, the cops just said, "Yeah, but you've got plenty of money to fix it!" (and of course they did nothing, even though I had the perpetrator's license plate number)

When I was due taxes back from the government, I had to fight for it & ended up only getting half of what I was due.

 

[packrat]

You think you aren't at risk?
A nice solar flare or an otherwise large EMP, and it all goes dark for a veeeery long time.
Or something more simple and local like a high voltage line getting crossed up with your incoming service.

The number of times that happens where I live goes vanishingly close to zero, and with most power being underground, several more sources of risk are remove. I also know that things would get replaced if the power company screwed up badly enough to break things.

Solar flares, those are spooky handwave stuff that isn't relevant, and EMP fries silicon no matter what its plugged in state is, so also not relevant.

Again, given the consistent reputation fo the Kenyan power company to stupid crap, proper power conditioning would seem a prudent step.

B>

 

[packrat]

I've witnessed it many places, two-tier (and sometimes three-tier) pricing & it's usually just because the expat has more money, or at least it's assumed.

When I had a guy hit & run my new vehicle, the cops just said, "Yeah, but you've got plenty of money to fix it!" (and of course they did nothing, even though I had the perpetrator's license plate number)

When I was due taxes back from the government, I had to fight for it & ended up only getting half of what I was due.

What the cops were actually saying was much more likely "where's our service fee?".

B>

 

[Killed_by_Death]

My brother-in-law was one of the cops who said it.

It wasn't a question of money/bribe, they just didn't want to get involved between two expats.
Yes, the guy who hit me was a drunken expat.

 

[packrat]

I'm not touching the likely dynamics there with a thousand foot circuit breaker. I will say that "rich people are at fault" isn't the conclusion I'd come to.

B>

 

[Killed_by_Death]

I would, but I lived it.

 

[agedhorse]

Note that many techs will not work on failed repair attempts by end users or other unqualified technicians.

My own shop policy follows this because there's no way to know what damage was caused by the original fault and what is damaged by the repair attempts.

 

[beans-on-toast]

I imagine that you have to be practical and inventive when you live in Kenya and do not have access to an amp tech. If the only way to have an amp serviced is to have someone carry it out of the country and take it to Europe, sometimes informed repair risks are worth it. Sometimes they are your only option.

 

[Kevin1960]

Note that many techs will not work on failed repair attempts by end users or other unqualified technicians.

My own shop policy follows this because there's no way to know what damage was caused by the original fault and what is damaged by the repair attempts.

The DIY'ers sometimes get in too deep and send up the SOS by finally giving in to the inevitable and finally agreeing to pay someone skilled to save their butts. Yes, I think many shops have this as SOP. Bringing in their "basket case" (Yes, actually saw one in a real basket in pieces) to get turned down is a hard lesson to learn. "No user serviceable parts inside" is not the manufacturer pulling your leg.

 

[Mr.Ace]

Maybe not so crazy.
If Kenya is on something like a 220 volt grid vs our 115-ish, they are already a lot closer to 400 to start with.
And the 400 volts really needs an asterisk because we don't know tha nature of that 400 volts.
Was it a bunch of spikes/surges, or continuous?
Still crazy that it got high enough to blow up his amp.

Definitely, I’ve seen 220/240v plugs jump up when a Diesel, or natural gas generator motor goes into overspeed. But a whole grid. That’s almost 2x’s the nominal voltage.

 

[Mr.Ace]

My Dad was an electrician for 35 years and I do remember him telling me that the gap inside a breaker between the contacts is not a great way to isolate you from large current fluctuations on the grid and the best insurance was the distance of total disconnection. The further the better. Just a constructive thought, I hope.

Transients