[ljoe1969]

i found a power supply and i want to know if it will work on a xylotex driver.

input 120 vac 50/60 hz 8 amps

output 24v 75 va

anyone tell me if this will power my xylotex board or should i look for another power supply?

[balsaman]

The input must be 0.8 amps. Output will be around 3 amps. What motors are you using. What is the current rating of them. Unless they are very small steppers you need a little bigger supply.

Eric

[ljoe1969]

i got them with the driver from xylotex. the 116in/oz that is come with the kit.

[balsaman]

It will be nip and tuck. See if you can find a little bigger one, or ask Xylotex to be sure.

Eric

[ger21]

THis would be a little better.
http://cgi.ebay.com/ws/eBayISAPI.dll...category=32720

It's a little pricey, though. If you're not in a hurry, you can usually get a liitle higher output for less money. This cost $135 new, though.

Gerry

[bcromwell]

If you are look for a cheap way to get pretty good power,

I took 3 PC power supplies that where rated for 12 amps on the 12v Feed and 15 amps on the 5v feed, I took and put them in series, Which give me 12+12+5 = 28V at 12 amps, and I picked up the power supplies for 5$ each at a computer surplus shop. They only thing you have to do to get this to work is to remove the 3rd (bottom) prong off each power supply so they will have a floating ground, and becuase I had a metal case, I used double stick tape as a dielectric to keep the three ps's from touch each other and the case.

It's not near as clean as some of the toroidal power supplies, but like I said I am only out 15$, and switching power supplies are very efficient.

[Mr.Chips]

bcromwell
I'm not electrical at all and don't understand putting 3 PC PS in series. Could you supply a little drawing.
To me in series means the output of one is fed to the input on the next... I understand the output, but don't know where the input would be.

This seems like a very inexpensive way to arrive at 28V and 12 amps.
Hager

[abasir]

Something like below I believe

[bunalmis]

No no no

You can not connect 3 PC power supply.

Serial connection not possible. Load can not equal share by 3 Smps and poor PS goes shutdown.

Also If you pull power from 12v but dont pull power from 5v, PC goes shutdown.

[abasir]

Have to wait for bcromwell connection diagram then :stickpoke
May be depend on PS type also?

[limbo]

If I understand correctly from the Xylotex datasheets these steppers are 13W each (2 coils of 6.5W). Suppose the drivers have 70% efficiency (a bit conservative), this means 18.6W draw from the supply per stepper. For three steppers this totals at 55.8W (roughly 2Amps), so I think you'll get away with using your original powersupply. Why not try first and measure the total current, before investing in another supply?

John

[bcromwell]

Originally posted by bunalmis
No no no

You can not connect 3 PC power supply.

Serial connection not possible. Load can not equal share by 3 Smps and poor PS goes shutdown.

Also If you pull power from 12v but dont pull power from 5v, PC goes shutdown.

abasir's Picture is exactly correct, And Any PC PS should be fine,

Yes you can connect 3 PS's together IF you make them have floating grounds (On the AC Side) and they can't ground to each other (IE, Since most PC PS's have metal cases, They can't touch each other).
Your amperage will be what ever the lowest rated amperage Leg in the series, IE, If you have 2 PS's rated at 5amps@12V and the last PS is rated at 6amps@12V you would end up with 36V@5amps.

Since my xylotex board will not handle 36V, I only used the 5Volt leg on the 3rd PS, so that I would end up at 28. You cannot just serial connect the 12V and the 5V on the SAME PS because they use a shared common ground.

I have been running my xylotex board with this config for over 3 months now and it works great..

Also If you pull power from 12v but dont pull power from 5v, PC goes shutdown.

To solve this I just used a 2 5V light bulb fixtures and one 12V Bulb, from radio shack, as a indicator light, Because if One PS out of the 3 is off the system still works, but with the lose of volts the steppers slow down, so the lights are nice to have.

I will post pictures of my PS when I get home.

Bryan

[bcromwell]

Originally posted by limbo
If I understand correctly from the Xylotex datasheets these steppers are 13W each (2 coils of 6.5W). Suppose the drivers have 70% efficiency (a bit conservative), this means 18.6W draw from the supply per stepper. For three steppers this totals at 55.8W (roughly 2Amps), so I think you'll get away with using your original powersupply. Why not try first and measure the total current, before investing in another supply?

John

He might be wanting it for speed, he has the amperage, but not the max voltage, the max voltage of the xylotex board is 30V.

[Mr.Chips]

Abasar,
Thanks for the drawing and thanks to the others that commented supporting this. PS are expensive and this will be a big savings to thoes of us builders that are building on a budget.

In your drawing you show Black, Yellow, and Red wires. The PS I took apart has these three colors, many of each color coming out of the circuit board from three areas.

Is it correct to assume that I can tape up all but one of each group of colors and use that one to attach to the next wire?

Can I also assume that the wiring color is standard, because these are all power connections to the drives in the original PS application?

In your original posting you mention "remove the 3rd (bottom) prong off each power supply so they will have a floating ground" You are refering to the ground prong on the power cable aren't you?

Hager

[bcromwell]

Originally posted by Mr.Chips
Abasar,

In your original posting you mention "remove the 3rd (bottom) prong off each power supply so they will have a floating ground" You are refering to the ground prong on the power cable aren't you?

Hager

I just use a pair of piers to brake of the 3rd prong of the PS it self, But you could cut/break the 3rd prong of the end of the Power cable.

[Stevenpats]

I would suggest installing a GFI receptacle to feed your PS if you cut the grounds from the 115v supply. A GFI compares current flow from hot and neutral, so no ground is needed. If any of the cases become energized for any reason, your regular circuit breaker will not trip and when you touch the case you will do the "60 cycle shuffle". If a GFI is installed it trips with leakage as little as 5 milliamps or so,mimizing risk to you and equipment. I was unaware that the DC circuit of PC power supply had any connection to ground, and if no ground is needed to operate then why is it connected in the first place ?
Steven

[abasir]

Hager,
Outputs from PC PSU are color coded as per my drawing [RED=+5V, YELLOW=+12V and BLACK=GND]. You'll see several wires of the same colors coming out from the PSU but inside they are all connected to the same area. I suggest you use several wires (of the same color of course) to connect to the next PSU. The 'bunch' has more current carrying capacity that any single wire.

[balsaman]

This may work but it is never safe to cut the ground off any electrical device. "Roll the dice and take you chances".

Eric

[Mr.Chips]

Thanks Brian.
Looking forward to seeing pictures of your PS.

It's all coming together.
Safety (GFI), Function, Design, Assembly Instructions, and Saving Money.

Hager

[bcromwell]

Here is a Pic of the Power supply, I am not 100% done as I still have to mount the connectors for the morors and the indicator lights.
As for 'breaking' the gound connection I wasn't to worried because they are mounted inside a large metal case and the case is grounded, But that is a good Idea on the gfi outlet.

The two PS's on the left of the case are Dell Server (2450 Servers I believe) because the had a good amperage on the 12v legs, and on the right is a common pc power supply that I am pulling the 5v leg from, and the Xylotex of of the remaining 12v leg.