24 volt supply.

[LeeWay]

Hey guys. I'd like some thoughts on the power supply that I picked up while shopping for some couplers and bearings. Surplus Center
I have heard about linear and switching supplies and I am wondering if this one is a linear and how would I tell the difference if it doesn't say so? Thanks guys. I also picked up a 24v fan from these guys. Its huge. Its made in Germany and it seems like a good one. I think it may help cool my shop in the summer too.
Thanks again for the help I get from you guys.

[LeeWay]

Okay Guys. I guess I will reply to my own post after 46 veiws without a peep.
I thought the question that I asked was a rather simple one. I also thought that since the usual link you guys give for Power supplies is back ordered 6 to 8 weeks, that others might also need a source for an inexpensive 24v power supply.
All this is assuming that this one will work. Will it and is this a linear power supply? Thanks again Guys.

[Dogsione]

Looking up the part number I found this:
http://onlinestores.imacination.com/...ut&-skipRows=9

[LeeWay]

Thanks Dogsi. This tells me that these are at a great price at Surplus Center.
This link here at Sola tells me more about it too and that they are indeed used in CNC applications.

Mine is used, but in good condition. These things are all pretty heavy anyway. They did have some of these left if anyone is still looking. Thanks again. I knew ya'll would help out. I was itching to get all this setup and tested.

[H500]

If the picture in the link is correct, then it is a linear supply. You can tell by the size of the transformer and the weight.

[LeeWay]

Thanks.
Is linear more or less desireable for a small CNC router?

[Al_The_Man]

I prefer linear over switching, in spite of being much heavier, You do not necessarily need a regulated supply like these are, but it is an extra bonus.
Al

[Jay C]

Originally Posted by Al_The_Man I prefer linear over switching, in spite of being much heavier

Why? And if you were using it ona small machine (like a Taig or Sherline mill) would that make any difference in your preference?

Jay

[nakchak]

Personally id choose a linear supply for the reason its much simpler to fix than a switching supply, also parts or substitute parts are readily available.

Switching power suppliestend to be smaller in sise and weight, pc power supplies are switching power supplies, ever wondered why a PC PSU rated at 200W weighs the same as one rated at 700W?, its because the only difference is the power rating of the transistors used and somes a beefier heetsink. The transistors used are often matched pairs and are usually difficult if not next to impossible to obtain unless u either buy 10,000 of them or find some on a cannibalisied/scavenged board

A linear DC powersupply usually consists of a transformer, some form of rectification (ac to dc) and then some smoothing capacitors to give a clean output. Often this is then followed by a voltage regulation stage and sometimes a further stage of smoothing. This tends to mean large capacitors which can weigh a few Kg, though normally much less than that. The heavy object is always the transformer, and depending on the power rating of it(VA) and how many taps(feeds from transformer) it posses's, the higher the number the more it weighs. Despite the bulk there relative simplicity makes them very easy to fix and cheap to build, especially if you hoard transformers.

nak.

[Al_The_Man]

The reason I go with a linear, is I have found them less susceptable to noise damage, spikes, etc. Also they are easy to customize/put together, and for servo/stepper applications you do not need a regulated supply.
Al

[ViperTX]

I would add to Al's remarks..."...regulated supply to supply the bulk DC voltage for the steppers and/or servos...." the control circuitry will still require a regulated supply in most cases.

Switchers were invented to reduce the package size (reduce the size of the transformers and capacitors), improve the efficiency (linears are very inefficient, switchers are generally in the 80 to 90 percentile range in efficiency), all this results in a switcher supply that is lower in cost, smaller package and more efficient then a similar rated linear power supply.

[Jay C]

ViperTX, that's my point Smaller, less heat, and I don't see myself needing to wrench on either type of supply. However, shipping a transformer adds up. Just trying to find out what people's thought processes are.

Al, you mentioned noise damage? Can you eloborate?

Thanks for the fedback guys,
Jay