Beomaster 3300 converting from 220V to 110v

6 replies
Hi, to convert a 1987 ish Beomaster 3300 type 2957 from 220V to 110 V can this be done by re-wiring the existing European transformer or does the complete transformer be replaced with a 110 V transformer.  I did read somewhere that B& O used one type of transformer that could be wired differently for 220 V and 110 V. Is there anyone who has experience with this. I used an external step down transformer for many years but decided to go for a cleaner look. Cheers, Huub

Location: Houston

Hubertus C Duivenvoorde
This is from the Beomaster 3300 Service Manual. Hope it helps.

Location: SF Bay Area

Thanks. The schematics are quite clear. I have noticed that most US Beomasters are type 2953 with the 120V.  Will there be any harm when re wired to the 110 V. It is within 10%

Location: Houston

Hubertus C Duivenvoorde
It might "work", but you should be cautious. The outputs of the transformer will be "off" by the same percentage as the percentage difference of the input voltages. This likely won't affect any regulated DC signals, but will affect unregulated AC signals. You would have to carefully study the schematic to understand the ramifications. I would be more concerned about the liability associated with such a modification. If this modification caused a fire in your home, would your insurance cover the damage? What happens if the receiver is sold and the next owner has an issue? If you swap out the transformer for the proper one, you would have an easier time justifying the change. Personally, I would look for someone parting out a similar machine. In general, there isn't much demand for transformers since they typically don't go bad. When people part out machines, the high failure rate items sell very fast (and at a premium).  This leaves the seller with the low demand items that they will often sell cheap just to get rid of them. YMMV, Glitch
Hi, thanks. I agree with your assessment. I was already leaning that way and your response confirmed my thinking. Re-wiring is easier but not a safe solution. Why else would B&O use for the USA a different type of transformer. I was able to source a 120 V transformer (type 2953) from Europe of all places.  The seller did the opposite of what I need to do. again thanks for your input

Location: Houston

Hubertus C Duivenvoorde
Maybe you can work out some sort of "swap" with the seller to save money? (Might not work due to the cost of shipping)
or
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