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Using a US amp in UK

The Sad Mafioso

The Sad Mafioso

Guest
Dec 25, 2011
26
0
35
Greater Manchester, UK
#1
Okey doke...so I'm trying to use a GK 800RB in the UK but I'm nervous about the difference between US and UK voltage (UK voltage is twice as much). I assumed that I could just use a [This invalid link has been removed], but apparently I'll also need a transformer to actually convert the voltage. [This invalid link has been removed], or is there anything else I would need? I'm guessing that people in the rest of Europe have had similar problems with US products so any help at all would be appreciated.
 
#3
cnltb said:
Doesn't the GK have one of those little switches that change voltage accepted?
Click to expand...
Not that I can see (might be some way of doing it on the inside). I wondered why I couldn't find a 800RB over here; didn't realise the voltage would be an issue. Wait...would using the -10dB switch alter the voltage? Sorry if that's a stupid question; I'm still a complete novice when it comes to electrical issues.
 
#4
Do not try to plug it into the UK socket without either changing the voltage on the amp or without using a real transformer.

I changed the voltage on a GK amp from US (110) to European/Russian (220) internally - it was not difficult, but it is a specialized procedure, but that was for a different model, so I cannot say if the 800rb would be easy. If you are going to use the amp in UK for a while, I suggest you take it to a qualifed service tech and let them do it. If it will be a one-off thing, I suggest to get a decent transformer (the one you posted probably won't work).
 
#5
The Sad Mafioso said:
Not that I can see (might be some way of doing it on the inside). I wondered why I couldn't find a 800RB over here; didn't realise the voltage would be an issue. Wait...would using the -10dB switch alter the voltage? Sorry if that's a stupid question; I'm still a complete novice when it comes to electrical issues.
Click to expand...

No, that doesn't change the voltage, its just an input pad. You can probably change it to work on UK voltage with a fuse change which should be accessible on the rear panel and a switch (perhaps internal). If you don't know what you are doing take it to an amp tech and they should be able to do it for your quickly are fairly cheaply.
 
#7
Marlat said:
You can probably change it to work on UK voltage with a fuse change which should be accessible on the rear panel and a switch (perhaps internal).
Click to expand...
Yeah, I've been trying to find a new fuse for it but they didn't have any of the kind I needed at my nearest electrical store (GK tech support told me it needs a 4A fuse specifically). The guy at the store also told me I'd need a transformer, but I thought I'd just check here to see if anyone knows what else I might need. If anyone could post a link of a suitable voltage transformer which would work that would help me out a lot (if I actually need one, that is).
 
#8
Try and find if you can internally adjust it so that you can use it in the UK (take it to a tech to get done).

If not you'll need a step down transformer. You'd also need one that can handle more than 50 watts. I don't know what the power draw of the 800RB is, but I'm sure that a several hundred watt amplifier is going to use more than 50 watts of power.
 
#9
GK 800RB is specific amp because this is the only RB series amp without option of switching cables inside from 110V to 230V. I was hunting for 800RB us made in 230V for over 2 years... of course you can buy external power converter or change whole power transformer Link Removed.

The ext. transformer that you sudgested is to weak, you need more than 50VA
 
#10
suvdecropp said:
The ext. transformer that you sudgested is to weak, you need more than 50VA
Click to expand...
Link Removed? It says it has a max load of 300VA, but I still don't know how much of that the GK will actually need. Is there any way to find out? I can't see it mentioned in the manual or on the amp itself. I know that the two speaker outputs are listed as 100W & 300W (it's a bi-amp), but that probably has nothing to do with it.
 
#11
That's the amplifier power listed on the back (what it puts out), not the draw. 100VA isn't going to be enough (the draw from the wall is never going to be less than the amplifiers rated output). I suspect it'll be something like 500-600 watts.

Can't comment on the GK itself, but amps tend to have it printed around about the power socket on the back. You could always see what size of fuse it has, that'll let you know the maximum it can draw before the fuse is tripped, could be a good target to aim for in terms of what transformer to use, but it might be worth emailing GK and asking.

You could always go for the safe option and having a higher current capacity than you actually require:

Invalid Link Removed
 
#14
You need to look at the case to see what 110v fuse should have been in there. It sounds like someone has been monkeying with it already if the fuse carries a 250V rating.

Watts = Amps x volts
= VoltAmps
= VA

Amps = watts / volts

You are lucky the fuse blew. Hopefully that has saved the amp.

Going by what the other guy said there is no option for you but to get a relatively heavy duty 110V power supply and use the standard fuse marked on the case.

The power supply must be good for the amps the standard main fuse carries at 110V.
 
#15
The Sad Mafioso said:
OK, so I've just taken the fuse out. It's about 1.5 inches and is labeled '4A' & '250V'. It's already blown so I'll have to get a new one, unless I'd need something different to get it working on UK voltage. Is there any way that I can work out from that what the draw will be?
Click to expand...

Did you plug it in at some point? I'd be worried if I bought an amp with an already blown fuse.

Watts = Current x Voltage, so the fuse could handle a maximum draw of 1,000 watts. Not sure why it's a 250v fuse though. The transformer I previously linked should do the job (granted, likely be a bit overkill, but better to have too much and not need it ...)


mouthmw said:
Not sure if it's smart thing to use 800RB there. I think the reason they weren't used in Europe is overheating because of the voltage difference.
Click to expand...

If you're using a stepdown transformer to run it at 110v, it wouldn't be an issue.
 
#16
Downunderwonder said:
You need to look at the case to see what 110v fuse should have been in there. It sounds like someone has been monkeying with it already if the fuse carries a 250V rating.

Watts = Amps x volts
= VoltAmps
= VA

Amps = watts / volts

You are lucky the fuse blew. Hopefully that has saved the amp.

Going by what the other guy said there is no option for you but to get a relatively heavy duty 110V power supply and use the standard fuse marked on the case.

The power supply must be good for the amps the standard main fuse carries at 110V.
Click to expand...
Underneath where the fuse goes in it says '125V', '8A' so does that mean I'd need a transformer that can handle at least 1,000VA? What the hell a 4A 250V fuse was doing in there is beyond me, but like you said hopefully the fuse blowing has saved the rest of the amp. So just to confirm: I should use a 125V 8A fuse (as it mentions on the back) and a transformer that can cope with 1,000VA minimum (8Ax125V=1,000VA)?
 
#19
dincz said:
Don't worry about the fuse's voltage rating. That's just a maximum design rating for the fuse itself and shows that it can be safely used at any voltage up to 250V. It doesn't relate at all to the supply voltage.
Click to expand...
makes sense

The critical thing is the amps. Your power supply must supply the case rated current at 110V, pretty simple. Nearly every amp states what it draws on the case where the power cable goes in.

I would go for a converter with half as much again to be on the safe side.
 
#20
The Sad Mafioso said:
Underneath where the fuse goes in it says '125V', '8A' so does that mean I'd need a transformer that can handle at least 1,000VA? What the hell a 4A 250V fuse was doing in there is beyond me, but like you said hopefully the fuse blowing has saved the rest of the amp. So just to confirm: I should use a 125V 8A fuse (as it mentions on the back) and a transformer that can cope with 1,000VA minimum (8Ax125V=1,000VA)?
Click to expand...

They should be the same thing (the fuses) it just struck me as odd it would have said 250v from a US device (they both max out at 1000 watts).

I'll also point out that Watts and VA aren't the same thing (well, not when it comes to AC, which is what you'll be using). However, it should be fine.

As said before, I think the transformer from RS that I listed should do the job.

Also, I hope your amp is ok. Hopefully the fuse bit the dust before anything else did. Always read the electrical requirements, particularly when buying something from abroad or taking something abroad.
 

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