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Buck / Boost tansformers



Uncle Ed
02-28-2010, 07:08 PM
I have ordered one of these for my welding use.

While the info is still bouncing around in my gray matter, I was considering putting together a write up on them for folks who may be confused about their operation.

I always wanted to be a teacher but I suck at it and spent many sleepless hours trying to think of ways to present the info in a clear and easy to understand manner. I may have succeeded.

It would cover some transformer basics, buck/boost specifics, some analogies, some drawings and maybe even some sheep.

Since it involves a bunch of typing and thinking and drawing, I wasn't going to do this unless there is some interest.

So, if any are interested, chime in.

Bluesman
02-28-2010, 07:47 PM
I have ordered one of these for my welding use.

While the info is still bouncing around in my gray matter, I was considering putting together a write up on them for folks who may be confused about their operation.

I always wanted to be a teacher but I suck at it and spent many sleepless hours trying to think of ways to present the info in a clear and easy to understand manner. I may have succeeded.

It would cover some transformer basics, buck/boost specifics, some analogies, some drawings and maybe even some sheep.

Since it involves a bunch of typing and thinking and drawing, I wasn't going to do this unless there is some interest.

So, if any are interested, chime in.

I'm interested. I'm not 100% sure what you are talking about but I'm always game for learning something new.CoolMan

KHK
02-28-2010, 08:04 PM
I am also interested.

jbman45
02-28-2010, 08:57 PM
Even just an overview would be interesting so we could sort of see what they are all about would be helpful. Anything you can share with us would be great....

KHK
02-28-2010, 10:59 PM
I found some Information on buck/boost transformers at. http://www.powertransformer.us/acmebuckboosttransformers.htm (http://www.powertransformer.us/acmebuckboosttransformers.htm)

This is an interesting link, they explain the requirements of this type of transformer.

Uncle Ed was going to buy a buck/boost transformer that was .750 kva to run his 200PI. A quick look at the .750 kva against a welder that is a 12000 watt unit says NO. But after looking at the web site, they supply the following formula;
amps = ((buck/boost)kva x 1000)/(step up volts)....... (.750 X 1000)/(230-208 )= 34 amps. So the final answer is YES UNCLE ED IS CORRECT!!!

jbman45
03-01-2010, 07:27 AM
Boy, what link! Some great information on that site Keith and although I understand quite a bit of electronics, this really helped understand the different types of transformers, especially the boost transformers. Not sure of the need though for out welders? Is it because they are made for up to 230 volt? and they will run more efficiently vs at 220?

Uncle Ed
03-01-2010, 01:36 PM
Anytime you have the option of using a higher AC voltage it's more efficient.

Power distribution relies heavily on the fact. Think of connecting 240V from town to town. The amount of conductor and the voltage sag.. Eeesh

matteh99
03-01-2010, 02:03 PM
I can see the advantage of having the correct voltage for your device. Just adding one of these between your welder and the wall doesn't seem to make sense to me. Yes higher voltage is more efficient for transmitting power over distances but every time you change voltages you lose some power. Converting 220 V down to welding voltages seems easier than converting 220file:///Users/fres/Library/Caches/TemporaryItems/moz-screenshot.pngV - 240V and then back down to welding voltages unless your welder doesn't like 220V.

Uncle Ed
03-01-2010, 04:29 PM
This whole thing started because my 200PI does not seem to like 208v and I needed to get up to 240v.

Plain transformer type welders are even more voltage sensitive. If a unit is wound to take 240v and spit out 20v for the arc, you are going to get 17v of arc force with a 208v input.

Machines need to have a good balance between arc voltage and current. It's part of the reason that some machines seem to weld smoother or have different arc characteristics.

If the machine is regulated then it has to draw more current to correct the voltage and that will cause undue strain even IF the unit can correct that far.

Why would I want to start my truck with a 1000 amp 10v battery when the starter is made for, and runs better, on a 800 amp 12v battery?

matteh99
03-01-2010, 09:12 PM
The same is true for higher voltages. You wouldn't use a 18 volt battery instead of a 12 volt one. Sure your lights would be brighter and your starter would crank faster but you would also burn stuff out.

I can definitely see the advantages to using the voltage the machine or system was designed to use.