Need Help!- Power Supplies ordered, now I fear they're the wrong ones?

[boblon]

Ok, you think I would have learned about assumptions and taking the easy way, but apparently not.

I ordered two PS's, thinking I'll just parallel them to get the current I need. But looking through this forum I'm not sure I should do that. Here's the deal.

I am ordering parts for an upcoming build. I need to run 3 Nema34 motors and one Nema23. Here's the particulars:

3 ea. - Keling KL34H280-45-8A 2.2mh/6.3a wired Bipolar parallel
1 ea. - Keling KL23H286-20-8b 6.8 mh/2.8a

I figured I need 14.539 amps total:

((6.3 * 3) + 2.8) * .67 = 14.539 amps.

Keling sells the

KL-4813 48v/13a supply.

Didn't seem quite large enough so I ordered two

KL-4875 48v/7.5a

Figured I'd parallel them for 15 amps.

So the question is, did I screw up? Do I need to source a single 15amp or better supply? Will the 13a supply suffice (the one I did NOT order)?

Or can I parallel them?

I'm putting a fair ammount of money in this build and if I really need to buy another supply I will (just hoping I don't have to).

Thanks,
BobL.

[doorknob]

You should be able to parallel two of those supplies without any difficulty.

[Al_The_Man]

Can you do it? yes, you can probably get away with it.
Is it the best/optimum way? Not really, look at the recent similar post and the subject of linear supply.
Al.

[boblon]

Yeah Al, that's the one that lead me to posting. Your responses in particular. I've cruised this forum long enough that I respect your opinion.

I don't want to 'just get by' with this build.

So, the next question.

Got any good (reasonably priced) sources?

Anybody want a deal on some power supplies?

BobL.

[doorknob]

The KL-4875 is a linear supply...

[boblon]

Ok, I must be missing one of the finer points here.

doorknob-(I appreciate the input) I take it your implying the fact that it's not a switcher changes something?

I see Antek has some nicely priced PS's.

For example: the PS-8N48N24 48v/16+ amps with 24v/2amp.

Could use the 24 volts for realys, limit/home swithces, etc.


Thoughts?

BobL.

[Al_The_Man]

I usually build my own so I usually pick up my toroid's from Antek.
He also lists on Ebay as Jonango.
Toroids are nice as either the main winding can be added/reduced or an auxiliary winding can be added very easily if need be.
Al.

[doorknob]

Originally Posted by boblon Ok, I must be missing one of the finer points here. doorknob-(I appreciate the input) I take it your implying the fact that it's not a switcher changes something? I see Antek has some nicely priced PS's. For example: the PS-8N48N24 48v/16+ amps with 24v/2amp. Could use the 24 volts for realys, limit/home swithces, etc. Thoughts? BobL.

Much of the earlier discussion about paralleling power supplies concerned the possibility that the regulated switching power supplies might end up "fighting" each other to maintain the desired output voltage.

Putting two identical unregulated linear supplies in parallel should not face that problem.

The Antek supply certainly looks like a capable one, and as you mentioned, it's nice to have some auxilliary power supply voltages available for use with accessories.

If I were in your neighborhood and you wanted to let the Keling supplies go for an attractive price with no shipping required, I might take you up on it. But I'm not convinced that it is necessary for you to make a change.

[UUU]

Why not run two motors off one supply and the other two off the other? You're still a bit shy on one side.

[boblon]

@UUU-Yeah I considered that but:

(6.3 * 2) * .67 = 8.442

Didn't think the 7.5 amp could handle it.

I don't know what Kelings return policy is, I will ask.

I really don't want to fudge on this build, I'm limited on my budget (blown that already). Don't want to try to save a few bucks at this point to the detriment of the build.

Thanks though,
BobL.

[boblon]

Ok, I talked to John at Keling and it's all good.

PS's will be going back and he's going to send me a 20a one

Thanks guys, I hate it when I do that !

BobL.

[UUU]

That sounds like the best outcome. Well done to Keling!