220V amplifier in 110V country... oops!

[mike7877]

As stated above, in the US a 240VAC plug is hot-hot-ground. A 120VAC plug is hot-neutral-ground. Equipment that expects neutral (i.e. zero potential, but separated from 'ground' for safety reasons) on that certain leg, if you wire hot to it, you're likely to blow it up; amateur electricians do this all the time wiring regular 110VAC circuits backwards.

If this model has an internal transformer, moving the taps or replacing the transformer seem like a far better idea. But again I'd let the manufacturer make that call, even if it is expensive.

Euro power would also be 50hz vice 60hz, which is generally not an issue with something like an amplifier but I wouldn't make that call for sure.

There are reasons these aren't easy-peasy conversions and why people aren't just regularly snapping up overseas bargains and running them on laundry dryer circuits.

For amplifiers I'd imagine the problem is only when going from 60 to 50Hz. If the bulk capacitors aren't +20-30% of what's strictly required (like is often done in higher end stuff so performance remains the same with more difficult loads).

 

[JustJones]

Could put in a new, I guess in Canada 220v , 20amp receptacle. In the US 240v are now run hot-hot-neutral-ground. 20 amp should use 12/3 wire it has 4 wires in it 2 are hot red and black, white is neutral and bare or green is ground. Hz shouldn't matter except for motors like in a turn table for instance might run slower.

 

[mike7877]

When I moved from the UK I brought some 240V items with me. I used a 2000W step-up transformer like this: https://www.amazon.ca/SEYAS-Transfo...rotection/dp/B099MSP9XC/ref=asc_df_B099MSP9XC

One option I'm looking at is a toroidal version - they have less internal resistance so there's less voltage drop during high current. The A18 uses a toroidal transformer itself - in post 10 I described what happened to my electrical from another similarly powered amp with toroidal transformer, it's funny/unexpected

 

[mike7877]

Could put in a new, I guess in Canada 220v , 20amp receptacle. In the US 240v are now run hot-hot-neutral-ground. 20 amp should use 12/3 wire it has 4 wires in it 2 are hot red and black, white is neutral and bare or green is ground. Hz shouldn't matter except for motors like in a turn table for instance might run slower.

In the basement near the amp in a closet I put fittings for a washer/dryer. Had old ones in there for a while, but after non-use for 7 years I sold them. I'm contemplating dryer plug adapter - using a dryer plug and wiring it to a portable self contained electrical box (like the wall but external) with standard dual 120V outlets. There's some concerns raised here that using two hots instead of a hot-ground could cause issue. Apparently Arcam stuff uses the same transformers and just uses different taps for the ones sent to different regions - ie. North America would use 110V, UK/Europe 220

 

[DonR]

One option I'm looking at is a toroidal version - they have less internal resistance so there's less voltage drop during high current. The A18 uses a toroidal transformer itself - in post 10 I described what happened to my electrical from another similarly powered amp with toroidal transformer, it's funny/unexpected

The one I posted in the link is an autotransformer so it has no galvanic isolation but at the same time does not have as much core or winding loss as the toroid in the Umi. It is as close to a hardwired connection as you can get.

 

[JustJones]

In the basement near the amp in a closet I put fittings for a washer/dryer. Had old ones in there for a while, but after non-use for 7 years I sold them. I'm contemplating dryer plug adapter - using a dryer plug and wiring it to a portable self contained electrical box (like the wall but external) with standard dual 120V outlets. There's some concerns raised here that using two hots instead of a hot-ground could cause issue. Apparently Arcam stuff uses the same transformers and just uses different taps for the ones sent to different regions - ie. North America would use 110V, UK/Europe 220

I wouldn't do that because as was pointed out you're doing hot hot ground without a neutral. That's not code in the US any longer , 240v uses 4 wire just different awg depending on amperage of the breaker. I don't know about Canada.

 

[JustJones]

You can see the schematic here.

Arcam Audio Schematics & Service Manuals

Arcam Audio Schematics & Service Manuals. The no. 1 FREE download site for High End, HiFi, Pro & Vintage audio Schematics & Service Manuals

audiocircuit.dk

 

[sam_adams]

So I've been looking for an Arcam A18 forever,

No voltage selector switch on the back?

Power supply schematic (from here):

 

[Prana Ferox]

Could put in a new, I guess in Canada 220v , 20amp receptacle. In the US 240v are now run hot-hot-neutral-ground. 20 amp should use 12/3 wire it has 4 wires in it 2 are hot red and black, white is neutral and bare or green is ground. Hz shouldn't matter except for motors like in a turn table for instance might run slower.

Just to be clear, you still only get 120VAC using phase to neutral. To get 240VAC you still need to go between two hots. Nothing has changed about how the power gets transformed up on the pole or how it comes into your house.

Forgive the cheesy drawing, it was the clearest I found image searching.

 

[JSmith]

No voltage selector switch on the back?

There is clearly, as is made for an international market... OP must have missed it;

https://www.arcam.co.uk/ugc/tor/a18/User%20Manual%20(English)/a18e_manual.pdf

Arcam - A18(Discontinued) - Integrated Amplifier

The A18 combines the latest component technologies and Arcam’s refined and careful engineering design approach to produce an incredibly natur...

www.arcam.co.uk

• Switchable mains power inlet 110-120v / 220-240v

JSmith

 

[sam_adams]

There is clearly, as is made for an international market... OP must have missed it

⟵

Jim Horne avatar gets quite the workout . . .

 

[Audio Science Pal]

Wouldn't there be a switch on the back if this was the case? Or did they just skip that step and left the 110v tap untapped (pun lol).

I saw a picture of one with an external switch, but apparently the actual product was dependent on what part of the world your unit was built for. Best thing is to call or send a note to the manufacturer and ask their advice.

 

[JustJones]

Just to be clear, you still only get 120VAC using phase to neutral. To get 240VAC you still need to go between two hots. Nothing has changed about how the power gets transformed up on the pole or how it comes into your house.

Forgive the cheesy drawing, it was the clearest I found image searching.

Yes, it's split phase the neutral will work for each 120v leg , there will be a double pole breaker connected to L1 and L2.

 

[JustJones]

Could put in a new, I guess in Canada 220v , 20amp receptacle. In the US 240v are now run hot-hot-neutral-ground. 20 amp should use 12/3 wire it has 4 wires in it 2 are hot red and black, white is neutral and bare or green is ground. Hz shouldn't matter except for motors like in a turn table for instance might run slower.

Ignore this it violates code. 240v receptacle with removable plug needs to draw at least 6 amps. Brain freeze. You could use a locked plug.

 

[mike7877]

Another question - does this have to be from a dual phase transformer to work properly/ideally?

Would using the hots from a 3 tap transformer - with the phases only 120 degrees - affect viability? ie. would the virtual neutral start jumping around?

 

[JustJones]

Simplest answer is step up/down transformer.

Simran AC-750 Watt Two Way Voltage Converter 750W Step Up-Down Transformer

Buy the Simran AC-750 Watt Two Way Step Up and Step Down Power Transformer today from Dvdoverseas.com 220Stores for a low price. International Voltage Converters are always in stock and ship fast

www.220converters.com

 

[Zapper]

Another question - does this have to be from a dual phase transformer to work properly/ideally?

Would using the hots from a 3 tap transformer - with the phases only 120 degrees - affect viability? ie. would the virtual neutral start jumping around?

Domestic power only uses 2 phases 180 degrees apart. If one phase is 120V, phase to phase is 240V.

Commercial 3-phase power has 3 phases 120 degrees apart. If each phase is 120V, phase to phase is 208V.

I would proceed as follows:

1. Check the back of the amp for the voltage selector switch as shown by @sam_adams. If it has one, switch it to 115V.
2. If not #1, open the cover and examine the power path between line in and the transformer. Can the wiring be changed as per the schematic shown in Sam Adam's comment? If so, get out the soldering iron and do it.
3. Don't want to solder? Then do your 240V extension idea. I don't know if it meets code or not, but there is no issue with the amplifier. The voltage is applied across the primary windings, and the primary doesn't care if the power is line to line or line to neutral. Line to line is balanced, so it is less likely than line to neutral (unbalanced) to cause hum.

 

[DonR]

Domestic power only uses 2 phases 180 degrees apart. If one phase is 120V, phase to phase is 240V.

Commercial 3-phase power has 3 phases 120 degrees apart. If each phase is 120V, phase to phase is 208V.

I would proceed as follows:

1. Check the back of the amp for the voltage selector switch as shown by @sam_adams. If it has one, switch it to 115V.
2. If not #1, open the cover and examine the power path between line in and the transformer. Can the wiring be changed as per the schematic shown in Sam Adam's comment? If so, get out the soldering iron and do it.
3. Don't want to solder? Then do your 240V extension idea. I don't know if it meets code or not, but there is no issue with the amplifier. The voltage is applied across the primary windings, and the primary doesn't care if the power is line to line or line to neutral. Line to line is balanced, so it is less likely than line to neutral (unbalanced) to cause hum.

I think for step 3 it would be much easier, cheaper and safer to use a step-up autotransformer.

 

[Zapper]

I think for step 3 it would be much easier, cheaper and safer to use a step-up autotransformer.

Maybe not cheaper, but you're likely right about easier and safer.

 

[DonR]

Maybe not cheaper, but you're likely right about easier and safer.

Cheaper if he doesn't get a sparkie to come and do the work.