Selecting a Power Supply

Hmmm, ther obvious answer would be go for 24v 14 amp (336watts) going any less than this is likely to give problems at switch on.
However, I'm not sure I'd even risk that, you should make sure the PSU is ok to drive a motor type load.
I'm reluctant to offer advice on which you may waste your money.
When in doubt go big 24v @ 20A would seem like a reasonable bet.
(I did see your other post but ran away and hid)
IT would be good to take the motor with you when you buy, see if they will let you try...?
Del

Thanks for the response. The one I saw and is for a reasonable price is 25A 320W. But the thing looks like the type you power computers with. It is about 6'x3'x1' big and is lightweight. Cost is about $100. Does it sounds like the right deal? What about bridging all the outputs?

If all of the outputs are 24V then you can parallel all of the outputs. But many supplies that look like computer power (a switching supply) have multiple voltage outputs. Make sure what voltage(s) is available.

No, this looks like one but it is not. All outputs are the same amps and volts. But to make sure I will ask the supplier before I do that.

If it has more than one identical output (at 24v) then I'd think you could bridge them together, but I'd only risk it if they are rated at the same volts and amps.
(Obviously be sure to join + to + and - to - sorry to state the obvious, but better safe than sorry)

$100 sounds ok-ish to me...do you really mean 6'x3'x1' (six foot x three foot x 1 foot)
Del
(BTW I tend to agree with Redfred)

"... sorry not '... Thanks for pointing that out. Otherwise I might have ended getting a sub station.

Ok... 215*115*50mm (L*W*H) this is more correct.

You have your information inside your question. WATT :240. AMP: 14. So you require a 24 volt supply capable of providing at least 14 amperes. Since your driving a motor with this supply, I would choose an unregulated supply because of possible back EMF from the motor. But this is nothing more than a preference on my part. This will provide only ON/OFF operation, but the unregulated supply can just replace the battery you are already using. What ever control circuitry you are already using will work quite well.

If you were here in the USA I'd recommend Acopian for their quick delivery and reliability. They do make 200-240VAC models but I have no idea about their export capability.

Nope, I am in South Africa. The product I saw is made in China "mean well S-320-24 MW -G2 series 320W single output." If you search the web you will see what it looks like. I don't know whether it is regulated or not. My guess with all the fancy electronics I saw inside it is regulated.

Here is the link http://www.meanwell.com/search/sp-320/default.htm

Yeah, they mean well. (Sorry I can't stop myself from a bad joke.)

This is a regulated switching supply. Likely it should work fine for you. I only say "likely" because I do not know your control circuitry. If I did, I might notice a need for some simple surge suppression like a diode and/or capacitor in the circuit.

In your specs something does not add up. In DC, Volts x Amps=Watts. So if your motor takes 240 watts, then it needs 10 amperes and not 14. Or if it needs 14 amps, then there are 24x14=336 watts. So which is it?? If you are not sure what it is, go to your friendly garage and ask for two car batteries to be connected in series, which will give you 24 V DC, then connect your motor to run and measure the amperes on a multimeter. Then you will know exactly what your motor requires. You don't need to buy the batteries for this test. Your friendly garage should have some batteries around the place and the whole test should not take more than 5 minutes. Also, take your motor to the place you intend to buy the power supply and let them test run it. A good, reliable vendor will do it and will also advise you. And stay away from from computer power supplies. As to the AC input power, do not worry too much about that. Just make sure that your demand does not exceed 15 amperes. Anything above that may trip your breakers. Wish you well

In your specs something does not add up.

Yeah, but the sums Volts x Amps=Watts are in an ideal world resistive situation the current could be a maximum or start up rating.
If it says 14A then it would be foolhardy to buy anything with a lesser rating don't you think?
Also manufacturers are usually pessimistic with their figure to cover themselves.
Del

Thanks for the advice.I went to the shop and they were kind enough to allow me to test the unit on my motor before I buy. Here is the facts. The 14A label on the motor indeed must be wrong or it could be that the manufacturer tested the unit under strain., or took the brake solenoid into account. 250W /24V = 10.4A. The power supply I got is a 350W output and is rated 14,5A. If the motor is running without load it uses 2.2A. When the motor is clamped to a dead still it uses 19A. In this position the motor will burn out but before that happens the automatic protection from the power supply will kick in.The next power supply in the range is a 450W 30A and is much more expensive and besides that if something goes wrong and a total jam result then this larger more powerful power supply will burn the motor.. I decided to take a chance and will measure the Amps in working conditions when the whole rig is built. Thank you all for the input. Hope this thread helps someone else with a similar problem one day. Thank you all for helping, I have learned a great deal. Greetings. OS.

Nice to get the feedback.
Glad the story has a happy ending, and it's refreshing to know there are some helpful suppliers out there still.
Del

You may not want to mess about like this, but. Your cheapest option is almost certainly to buy two PC supplies. Parallel all the 12V supplies in each then put the two is series. I don't know if the outputs are floating, so you may need to isolate the earth (with possible violations of safety issues).

The up side is that once you have made up the harness, then if they fail on your travelling show you will be able to get replacements from almost anywhere.

The specs. on PC PSUs are not always clear so check carefully.

You will need to mimic the power good signal from the mother board (just short to the local 0V I think).

Thanks. It may be cheap for some one that does not have the resources but have much time on hands. I have a budget but time is my issue. I got the power supply for $90. It is working. I think when there is a failure they can for emergency take two car batteries parallel. I could include an emergency kit which includes some jumper cables with the right fittings/plugs as well as instructions.

I am busy with other stuff and in between updating this thread. Did not think. The batteries must be in series not parallel. 2x 12volt batteries in parallel will stay 12Volts but will have more amperage. Thanks for pointing that out so discreetly Randall. But it was too late to edit it.

Look keep it simple , borrow 2 X 12volt batteries set up your system hook up a digital ammeter with minimum,maximum and average recordings run your operations in whatever configuration you need. Note your readings starting and running under load and purchase a power supply to suite with surge capability to handle staring load. Actually if you have a small MIG welder hanging around [ smallest about 90 Amp] you can use that it will work perfectly well you can even alter the voltage range to vary the speed of the motor.

Haven't thought of the mig welder. Good idea for future when in need of DC power.