100V amp to modifying 220V - Peavey 5150

venndi

Member
2011-08-24 7:47 pm
Hi,

I bought a 5150, and that is a japanese version, so it works on 100V. Can be somehow done, that it works on 220-230V? I know there is a step down converter, but it would be better without it.
So, I found a schematic about 5150, and if you scroll down, there is 3 version of transformator.
1. Domestic (USA) 120V
2. Export (EU) 220-240V
3. 100V (Japan).
On the japanse version, there is an unsoldered wire (BL - blue I think).
So, the standard wire colors are brown (BR) 100V, blue 120V...It is possible to soldering these two cables together, then it would working with 220V? Can be somehow done to works on 230V?

https://www.thetubestore.com/lib/thetubestore/schematics/Peavey/Peavey-5150EVH-Schematic.pdf
 
I’m afraid not. It’s possible from what you’ve said that a Japanese model can be converted to 120v by using the BL wire instead of black, but soldering those two together will short part of the winding and destroy it. There does not appear to be a path forward to a 220v conversion with this transformer. Maybe peavy can sell you the export transformer?
 
Identify the transformer type number and if it has the BL unused, disconnect the wire going to BA and connect it to BL.
Wire the amplifier with a 3 core power cable. REMOVE the capacitor of death, the one that goes to the switch between Live and Neutral and fit the earth wire from the three core mains lead, to the chassis.
 

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PRR

Member
Paid Member
2003-06-12 7:04 pm
Maine USA
www.diyaudio.com
It is very-very unlikely the 100V version has a 230V tap. (100V + 120V is more likely, but not proven.)

This is a BIG amp. 120W output suggests 300 Watts from the wall. This is a 30-50 pound lump. Getting a new PT shipped from Peavey to you will be brutally expensive (the iron won't be cheap either). Mercury Magnetics may have this part, but they may charge more than Peavey. An external step-down is an obvious path, but just as heavy; and while 230V-115V is common, I have never seen 230V-100V.

If you live in a place (where?) that has small re-winding shops, you *may* be able to get the stock PT re-wound. If the 100-120-230V primary is on the outside, this may be "trivial" (to a GOOD rewinder). More often the primary is on the inside, forcing a major re-build, on an amplifier which would not tolerate any mistake.
 

venndi

Member
2011-08-24 7:47 pm
Actually there is a peavey 5150 PT where I live (Germany), it cost 160 Euro, plus the expert cost 100-150 Euro, just too much.
Aslo I found a used step down transformer for 230V-100V with 700W for 50 Euro, which would be enough since the 5150 is 500W, but would be nice to modifying just inside of the amp.
 
With your method would be 220V or 120V? Also are you sure that it works in that way?

Unused taps are always left unconnected. If there are other windings sometimes that need a series or parallel connection to be made but that is not applicable here.

Transformers are electrically isolated coils of wire that are coupled magnetically to one another. The ratio of the windings from primary to secondary determines the ratio of voltage and the inverse ratio of current. A transformer designed for 220 volt service vs. 110 will have twice the number of primary windings and probably a smaller gage wire (because current will be 1/2 and space will be needed for the additional windings). This is why you are unlikely to find a transformer that can handle both incoming power types with simply an additional tap. If you look at Hammond's tube amp transformers they have 115v versions and “universal” versions. The universal versions have multiple windings that are connected in series or parallel to accommodate a wide range of input voltage. They have taps for small adjustments.
 
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mandu

Member
2010-05-22 5:27 am
higher powered devices, if there is a transformer that can be connected to 110 or 220 volts will have 4 wires on the primary. These types are designed to be connected in parallel for 110 v or 220 v in series. Not a single tap as in the drawing. The tap may be 110/120 volts connections, but don't trust anyone's word. Best is to get a 240/110 auto transformer which when connected to 220 will output nearly 100 volts. Regards.
 
Identify the transformer type number and if it has the BL unused, disconnect the wire going to BA and connect it to BL.
Wire the amplifier with a 3 core power cable. REMOVE the capacitor of death, the one that goes to the switch between Live and Neutral and fit the earth wire from the three core mains lead, to the chassis.

DANGEROUS RECKLESS WRONG ADVICE.

If anything, it MIGHT convert a 100V primary to a 120V one but it will NEVER EVER CONVERT IT TO 220/230/240V which is what the OP is asking.

Your unqualified suggestion hints at it being possible, which it is NOT.

C´mon jonsnell, you are an experienced Tech, what were you thinking?:troll:

Leave it open with no wire connected
Again.

Did you read the thread title?:
100V amp to modifying 220V
 
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