help on converting and dropping voltage

Thread Starter

Deimok

Joined Aug 17, 2005
3
Hello all!
I am trying to convert and reduce voltage from eletrical outlet (120v) to DC (86v). I'm building a DIY overhead video unit. The bulb is 86V, 360W. Can anybody help me? Post circuit pic?
 

thingmaker3

Joined May 16, 2005
5,083
Your transformer needs to output just over sixty volts rms. (86/√2 = 60.8) The transformer secondary will have to handle more than four amps. (More is better. Power surges happen.)

I'm not very familiar with these bulbs - but are you sure they need DC? If they can run on AC, then the transformer output would need to be 86 volts.
 

Thread Starter

Deimok

Joined Aug 17, 2005
3
The halogen lamp runs off of AC or DC(not too sure) I think, they are similar to the floodlight lamps, just that they go into overhead projectors. I was trying to get away from putting in a transformer. On a budget. Right now I am using a dimmer to knock down to approximately 86V. This is not the best way I think
 

Texas

Joined Aug 17, 2005
2
Most filament type devices, valves included, rather AC and DC. DC 'tends to wear-out the filaments - not sure how but it does.

DC in valves is good because you can drop some hum but the life shortening is a no go.
 

pebe

Joined Oct 11, 2004
626
Originally posted by Deimok@Aug 19 2005, 05:29 AM
The halogen lamp runs off of AC or DC(not too sure) I think, they are similar to the floodlight lamps, just that they go into overhead projectors. I was trying to get away from putting in a transformer. On a budget. Right now I am using a dimmer to knock down to approximately 86V. This is not the best way I think
[post=9725]Quoted post[/post]​
A 300W 86V lamp has a fairly thick filament that's quite bobust. I think your exisiting dimmer is probably the best way.
 

Thread Starter

Deimok

Joined Aug 17, 2005
3
Thanx all for the help! I decide to stick with the dimmer switch for now until I can come up with a better setup
 
Top