Rewiring 117-230V pwr transf.
- Thread starter Triodal
- Start date
Short Answer : no
Long Answer: Unless your transformer is a multi tap design and has this already you cannot 'rewire'.
A transformer is a physical construction of windings that work with the magnet to 'transform', and that does not work in any kind of variable fashion. A mulittap is effectively several transformers in one.
If your product is available in EU/AU voltage as well as US voltage, chances are you can acquire a replacement to work in SG, though this varies from very simple jobs to pointless complex replacements . Quite often some power input circuitry is on the circuit board with the signal processing stuff, so any modification is finnicky. Also, it is not a case of going to Sim Lim and getting a replacement,
That said, several Marshalls, most of SWR, later Demeter, some Mesa Boogie, Alembic can be internally rewired, and I have done work to these. You may need the schematic from the manufacturer and thier cooperation varies, though I have not had any difficulty in my dealings.
If you are stepping down to run a power amp, you'd be better off getting a 220-240v version as your are probably carrying a fairly hefty tranny mainly becuase you need the ampereage, but if it is a preamp pr efx unit and you are using a Hefty step down, you are doing something silly. A preamp or efx unit has very low current draw,even valve or tube preamps, and you can use an inline lightweight step down tranny.
Long Answer: Unless your transformer is a multi tap design and has this already you cannot 'rewire'.
A transformer is a physical construction of windings that work with the magnet to 'transform', and that does not work in any kind of variable fashion. A mulittap is effectively several transformers in one.
If your product is available in EU/AU voltage as well as US voltage, chances are you can acquire a replacement to work in SG, though this varies from very simple jobs to pointless complex replacements . Quite often some power input circuitry is on the circuit board with the signal processing stuff, so any modification is finnicky. Also, it is not a case of going to Sim Lim and getting a replacement,
That said, several Marshalls, most of SWR, later Demeter, some Mesa Boogie, Alembic can be internally rewired, and I have done work to these. You may need the schematic from the manufacturer and thier cooperation varies, though I have not had any difficulty in my dealings.
If you are stepping down to run a power amp, you'd be better off getting a 220-240v version as your are probably carrying a fairly hefty tranny mainly becuase you need the ampereage, but if it is a preamp pr efx unit and you are using a Hefty step down, you are doing something silly. A preamp or efx unit has very low current draw,even valve or tube preamps, and you can use an inline lightweight step down tranny.
If you tell me what model you have and post your power section schematic I can tell you whether it can be done. Mesa Boogies tend to be field replaceable as opposed to multitap - viz. you may need to replace your tranny with one with the approapriate rating , and if you are clever you can get one from Hammond Engineering, otherwise you may have to get a tranny from Mesa Boogie.
Triodal said:
From the 'Schematic' you sent, it has a multitap transformer. It is a 30 minute job and you should be able to rewire the transformer in series for 220-240v.
The 'schematic' you sent is a hand sketched one and there is an error referring to 'live' as 'neutral' - this is potentially fatal if you don't know what you are doing.
However a competent serviceman can sort this out no problem.
From: Triodal
To: 0vid
Posted: Sat Dec 23, 2006 2:25 pm
Subject: power tranf.
Thanks...Will take note on that error..Should i change the cathode fuse value after the conversion or just leave it as 1 amp?I know the main need to change..
I cannot see the whole schematic to be frank. What you have is a hand drawn rewiring sketch, and some instructions to move jumpers. You would have to change fuses in mosst cases of transformer tap changing.
To: 0vid
Posted: Sat Dec 23, 2006 2:25 pm
Subject: power tranf.
Thanks...Will take note on that error..Should i change the cathode fuse value after the conversion or just leave it as 1 amp?I know the main need to change..
I cannot see the whole schematic to be frank. What you have is a hand drawn rewiring sketch, and some instructions to move jumpers. You would have to change fuses in mosst cases of transformer tap changing.