24v stepdown transformer question

[christhomas]

hey guys, new here. finally made an account on a forum i peruse quite often.

I have acquired a 1'' drive electric impact. not a battery powered one. it was used in a military application and originally had a NATO slave receptacle plug on the end. it ran off of a 24v application. i am curious if i buy a step-down transformer i can wire it somehow to use this bad toy in my garage. any input welcome. thanks

 

[Strouty]

What amperage does it draw?

 

[christhomas]

i will have to check. its in my storage unit currently

 

[PaulyC]

being that the slave receptacle is meant to be plugged into a vehicle or gen set, your impact is a dc motor. depending on how the motors armature and field windings are wired, it may or may not run if you feed it ac from a transformer. also, you will have to source a transformer that can handle the amperage. youre not going to be able to use a door bell xfmer.

im not an expert on motor controls or anything so maybe someone else knows something i dont. you might find something like a vfd that can run it or something.

 

[manwithtools]

Need to know - AC or DC and operating amperage. Transformers and power supplies are available for both. You may not like the price depending on requirements.

 

[wyliesdiesels]

Probably would be cheaper to get 2 12v deep cycle batteries wire them in series and put them in a cart. Then get a 24v battery charger.

A transformer and rectifier to run that is gonna cost a pretty penny!

 

[Strouty]

I think it would be better to sell it and buy a regular 120 volt or rechargeable one. If you have a military truck or genset, then you could keep it for that application, but seems like a lot of work for little gain.

 

[Shiftless]

Probably would be cheaper to get 2 12v deep cycle batteries wire them in series and put them in a cart. Then get a 24v battery charger.

A transformer and rectifier to run that is gonna cost a pretty penny!

^^^^^^^^
on Wylie's idea
I wouldn't be surprised if that tool drew 50 amps.

But Strouty has a good point. The advantage of having a 24 volt DC hammer is that then you could run it off of 2 RV batteries when you in the field are far away from a receptacle.
I once did a job for some people who needed me to rewire and/or replace some underground sprinkler control valves that were often under several inches of water and hundreds of feet from AC power.. I had a small pump and a deep cycle battery that I pulled around in a little wagon. Worked great and was WAY better than bailing out the pit with a cup!

 

[sberry]

This is an idea while it "could" work its an awkward, expensive and inconvenient. See if someone wants that gem.

 

[G_P]

Its probably going to need a big transformer that will cost a fortune and weigh as much as a car battery, and possibly a rectifier that will need a heatsink and maybe even a cooling fan.

 

[zmaxmotorsports]

Its probably going to need a big transformer that will cost a fortune and weigh as much as a car battery, and possibly a rectifier that will need a heatsink and maybe even a cooling fan.

 

[ctfjr]

Its probably going to need a big transformer that will cost a fortune and weigh as much as a car battery, and possibly a rectifier that will need a heatsink and maybe even a cooling fan.

here is a 14 amp supply for $25 (and it weighs little):
http://www.ebay.com/itm/Regulated-S...210936?hash=item53ee4b7ff8:g:i5UAAOxyKsZRyBG2

A little search on Ebay & you can find plenty of these, even much larger. I've purchased a couple from Hong Kong in the past to make a 24 volt charger for my gov surplus diesel genset. They are fine.

You really need to know the amp draw and the max stall current of that drill in order to size a power supply correctly. Of course you could also invest in a larger capacitor to help you get over the 'start current' hump.

 

[Shiftless]

That tool is a one inch drive impact wrench for military applications. I'm betting it draws a MINIMUM of 50 amps at 24 volts. That isn't even 2 horsepower.

The half inch HF electric impact wrench draws 7 amps at 120 volts which is 840 watts.

If the 24 volt impact we are discussing was rated at (very conservatively) twice the power of the harbor freight half inch model, it would draw 1640 watts which at 24 volts is 68 amps.

Am I thinking clearly on this??? (I realize that D.C. is probably more efficient than A.C.)

 

[Rookie2]

Here is a 1/2" military:
http://www.ebay.com/itm/7863-Lugmas...597985?hash=item4873b09661:g:qFEAAOSwuMFUaoNv

also
http://www.dcimpact.com/impact_wrench_features.php

 

[dave*99]

I would think 2 car or lawn tractor batteries would run it. If you are compelled to build a power supply, then 2 of these in series should work:


http://www.ebay.com/itm/HP-Proliant...007037?hash=item43eaace07d:g:R-QAAOSwZQxW2LK5

If this link expires, then search "HP Proliant 1200W power supply" on ebay to find similar units