High Voltage Electrical Help

[Dynoroom]

Okay, this is out of my league.   

I have a Hewlett-Packard power supply. It's designed to be used @ 440 volts AC input with an output range 0 to 40 volts DC @ 0 to 100 amps.   

What I'd like to know is.... I have 220 volts at my shop. If this unit is wired up at 220 instead of 440 will I still be able to use it at 1/2 the output? Meaning 0-20 volts DC & 0-50 amps. I want to use this power supply with my engine dyno.

Any help will be very much appreciated. Thanks   

[bbarn]

Probably not going to work right out of the box. 440 is usually 3-phase power, 220 is only 2-phase. If you have 220 2-Phase power available at your shop, look into a rotary phase converter. This is a device which will take your 2 phase power and generate the missing third leg for you. With a rotary converter in place, you hook up to your 220 shop power to your device, then connect the output of the rotary converter as the third leg.

[Seldom Seen Slim]

I'll expand on what BB said -- but add some other stuff from my experience.

The 440 VAC unit is maybe built for 3-phase -- maybe not.  First of all you'll need to determine which one of those two choices it is.  If it's for regular (called single-phase) you're in luck.  All you'd need is a step-up transformer to get your shop 220 up to 440.  By the way, once you get above regular household 120 you sometimes get little variations -- like maybe it's 440, maybe it's 480.  Check it out -- there are often taps available on or in the unit to allow some adjustment of the input voltage.  You'll want to be sure to get this part of the deal correct.

If the 440 unit is built for 3-phase -- well, BB is correct -- but a rotary inverter is pretty inefficient.  It's basically a motor (running on what you've got, or, in this case, 220) that's spinning a generator that makes what you want -- in this case, 440 3-phase.  It'll be physically big and make a bit (maybe a bunch) of noise, too.

If you want to do the conversion on the cheap I'd suggest you ask your local commercial electrician (guys that work at household levels might not know how to do this) about using the regular single-phase to make "sort of" multi-phase.  We had a three-phase motor on the big air compressor at my business - but only single phase was available.  The power company and electrician hooked it up using both sides of the single phase as two -- and the neutral leg as the "third" phase.  It was inefficient -- but less costly than having a rotary converter spinning, especially since the rotary unit would have to either spin constantly to be available when the compressor needed to come on - or it'd have to be set to come on and up to speed before the compressor could start -- which might be too long for the process.

Ask your local folks or your power company -- they might be able to get the thing running for you without a big hassle.

[Glen]

Mike, talk to Bobby Sykes jr. or Larry Lindsley they should be able to tell you.

[bbarn]

I'll expand on what BB said -- but add some other stuff from my experience.

The 440 VAC unit is maybe built for 3-phase -- maybe not.  First of all you'll need to determine which one of those two choices it is.  If it's for regular (called single-phase) you're in luck.  All you'd need is a step-up transformer to get your shop 220 up to 440.  By the way, once you get above regular household 120 you sometimes get little variations -- like maybe it's 440, maybe it's 480.  Check it out -- there are often taps available on or in the unit to allow some adjustment of the input voltage.  You'll want to be sure to get this part of the deal correct.

If the 440 unit is built for 3-phase -- well, BB is correct -- but a rotary inverter is pretty inefficient.  It's basically a motor (running on what you've got, or, in this case, 220) that's spinning a generator that makes what you want -- in this case, 440 3-phase.  It'll be physically big and make a bit (maybe a bunch) of noise, too.

If you want to do the conversion on the cheap I'd suggest you ask your local commercial electrician (guys that work at household levels might not know how to do this) about using the regular single-phase to make "sort of" multi-phase.  We had a three-phase motor on the big air compressor at my business - but only single phase was available.  The power company and electrician hooked it up using both sides of the single phase as two -- and the neutral leg as the "third" phase.  It was inefficient -- but less costly than having a rotary converter spinning, especially since the rotary unit would have to either spin constantly to be available when the compressor needed to come on - or it'd have to be set to come on and up to speed before the compressor could start -- which might be too long for the process.

Ask your local folks or your power company -- they might be able to get the thing running for you without a big hassle.

I knew someone would have more background on it. I actually built my own rotary converter using an appropriate rated 440 motor and run it off of 220. It will not auto start on 220, but it will run once it is spun up by hand. The 220 will keep the motor running and I just tap off the third leg of motor into my lathe and everyone is happy. It's not a real steady output and there is no line conditioning, but for a 13" Clausing it works pretty well. For what he is running, I don't know how sensitive it is to voltage flux so I didn't want to go there.

[Dean Los Angeles]

Ask your local folks or your power company

That's a good one! My power company would threaten to toss me in jail if I asked to do that. Most electricians wouldn't be interested unless the liability to eating regular ratio is way down.

Do you have a part number, any info from a label, anything? How many connections are there on the incoming power? There are a large amount of dual voltage power supplies out there that just need a jumper moved. Can you post a picture?

[Dynoroom]

Ask your local folks or your power company

That's a good one! My power company would threaten to toss me in jail if I asked to do that. Most electricians wouldn't be interested unless the liability to eating regular ratio is way down.

Do you have a part number, any info from a label, anything? How many connections are there on the incoming power? There are a large amount of dual voltage power supplies out there that just need a jumper moved. Can you post a picture?

Hi Dean. The part # is 6456B. Several come up on Google but no hard info. Maybe you can find something?

Here's a couple of pictures.....

And here is some online info I found......

Hewlett Packard 6456B
36V/100A DC Power Supply, Refurbished
Rated: 0 to 36 V @ 100 A
Regulation: 0.2%
Metered
CV/CC
Programmable
 
 Product Information
Ordering Info 

 
 
HP / Agilent 6456B Power Supply provides an AC line loss protection circuit which monitors 3-phase input and cuts of SCR's and opens output bus if a phase drops out; operation resumes when AC input returns to normal. The voltage and current outputs of the supply can be programmed by a remote resistance, or a remote voltage source. 3-phase input with various voltage options.
 

[bbarn]

Here is a spec sheet, still looking for a schematic

http://www.nationaltestequipment.com/docs/HP_6483C_info.pdf

Worst case:
http://www.manualsplus.com/manuals/AGILENT%28HP%29/6456B

[Dean Los Angeles]

Because of the AC line loss protection circuit you can skip the Rube Goldberg ideas. If it doesn't have 460V 3-phase it won't run.

Sometimes the free stuff costs more than it's worth. You need to buy a rotary converter.

There are tricks you can do with motors that won't work with this.

1. Have the electric company supply 460V 3-phase. Most won't supply to a non-business customer.

2. Move to somewhere that has 3-phase. Yeah, right.

3. Buy an electronic converter. Probably more than your racing budget.

4. Buy a rotary converter. Sadly, there are 220V single phase to 220V 3-phase converters all over the place. 220V single phase to 460 V 3-phase converters are not as easy to come by, and expensive.

[desotoman]

Mike,

Do you have single phase or three phase 220V at your shop. Most industrial parks have three phase. It looks like this unit only draws 7 amps at 460V. three phase. If your shop has 220V. three phase you could use a transformer and step up the voltage to 460V. three phase. You must remember when doing this your Amperage would be cut in half. So you would need to feed the transformer with at least 20 amps at 220V 3 phase to be able to get the 7 amps you need at 460V. three phase.

Some times you can find used transformers cheap sometimes not. I can tell you they will always hum, some louder than others. They also take up room.

I don't know what this unit costs but it might just be better in the long run to get one that fits your power source.

Hope that helped,

Tom G. 

[Dynoroom]

Yes I do have 220 3 phase at my shop. I think my neighbor (industrial park) had 440 plumbed in by SCE. I'll check.

Thanks for the input so far.

[jdeleon]

Dyno,

Is this power supply to replace the the console power supply on a SF901?  If so, i might have a spare that belongs to another engine builder down the road.

[Dynoroom]

Dyno,

Is this power supply to replace the the console power supply on a SF901?  If so, i might have a spare that belongs to another engine builder down the road.

Thanks but no, it's so I can run ALL the other electronics that keep popping up. When we run high hp engines we can sometimes have issues with power.

An example would be an efi system that was correcting the fuel curve as the voltage was dropping or fuel pressure dropping as the power/flow requirements go up.

And yes I too have a spare console power supply, "just in case".

[Dean Los Angeles]

You can buy a 12VDC 10A power supply for about $200. If you are going to spend anything close to that to get that old dog running I would just buy the new one.

[McRat]

If you are going to be throwing away any computers, that power supply gives 12v and 5v (for running engine sensors) and about 150-500w total usually (10amp+).  I use them for doing bench experiments with gauging instead of lugging a car battery around.  I have an El Cheapo (Extech) brand variable DC supply also, but it's display took a poop in less than 6 months of light operation.

If you got that 460 DC supply cheap, what the heck.  Get a fire extinguisher and plug it into 230 and see what it does.  If it's solid-state, it might overheat with low voltage, but then again, it might work fine.  The power supply tries to develop the right voltage from what it's given, and I would not be surprised if it worked fine up to 50 amps.