View Full Version : Power Supplies


Nightshade
01-27-2006, 04:32 PM
Hey all :wave: ...I was wondering where I could find one of these MG power supplies that everyone talks about.

If I'm running a 4 x 8 layout with two to four lanes on it (still deciding), and running Super G+ and X-Traction chassis, could I get a power supply from McMaster-Carr or WW Grainger or some such?

And if so, what should I look for (e.g. voltage/amperage/adjustable capabilities, etc.)? I'm not sure what I need......

Nightshade
01-28-2006, 11:10 AM
Ok....nevermind...just go to hoslotcarracing.com

I got it, I got it. :thumbsup:

AfxToo
01-28-2006, 12:11 PM
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AMX
01-28-2006, 10:52 PM
I have ONE 0-20 volt 0-50 amp Raytheon (you know, the Patriot Missle people?) lab grade supply left if you want a much better one than any of those....like 1000% better.....

New this thing cost over 10 grand. It is Avionics lab grade...

I would sell it for 300 bucks.....perfect condition....just an FYI

Nightshade
01-29-2006, 09:41 PM
Hey thanks AMX, (I worked for Raytheon from 1997 - 2000, btw) but I've already purchased one. I also went with a lab grade unit too as they are readily available to me and I thought it might be a smoother unit.

AMX
01-30-2006, 12:37 AM
What did ya get and what did you pay?


Ray in Dallas?


Just wondering.

Yes lab units are far better if for no other reason than THEY WON'T BURN YOUR HOUSE DOWN. I have seen so many of those crap Chinese supplies shoot fire out the vents it is not even funny.

I only get top notch tested lab equipment (supplies, spectrum analyzers, scopes, generators, amplifiers, meters, oscillators, etc.) that we personally go through completely BEFORE we get them and prove they work in a photo when we sell them.

AfxToo
01-30-2006, 07:59 AM
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Nightshade
01-30-2006, 11:02 PM
Hehe, gotta love power supply discussions...I think It's an HP 6002 and I'm paying shipping from Florida. Otherwise I would have picked up a Tek unit.

I was in Florida for 2.5 years and Kwajalein Atoll for 1 year.

AMX
01-31-2006, 01:06 AM
On the crap power supplies- :freak:

I have seen with my own eyes Astrons, Vista, Pyramid, Ten-Tec (which is a damn good continuous duty unit), and Dell (proprietary computer supplies) pour smoke, shoot sparks and emit flames out of the cooling vents. I have almost burned houses down with the above named devices.

I now completely shut off computers when they are un attended because something as simple as a computer power supply can do this. I also have smoke detectors directly over every unit like this in the house including computers. The first sign of trouble seems to typically be smoke :hat:

It is FAR more common of an occurance with supplies like Astron, Pyramid or the crap "Tec" supplies. I have been in a dimmly lit room on a Ham radio and had it go dead and seeing what looked like a fireplace burning in place of a power supply more than once.

I will not let that type of crap in my house ever again and this includes UNDER RATED Dell computer power supplies. The one that caught my curtains on fire was about HALF the rated wattage for the mother board, but that is totally different story. I am surprised they are not sued into oblivian.



On the Astron or Pyramid thing (or any other asian made crap power supply) just do your own research on any Ham board, or ask any Ham radio operator and these types of occurances will easily be verified. The component tolerances are far to lax and the fact that even within those tolerances the components do not LIVE UP TO the rating.....this is common knowledge.

The caps explode, the thermisters or fuse breakers don't give before something else goes pyro in the unit, the traces melt off the board and lay accross other traces causing direct shorts to things that explode, the transformers are filmed with what must be gasoline soaked crepe paper, etc. etc.


Fact is, and you can debate this if you like, or make yourself feel better if you own one of these units, that the lab supplies are built for burn in, or continuous duty applications where they run for YEARS straight without stopping.

You can't run an Astron for 24 hours straight (probably more like 2) without it going flambe on you.

So, there is my first hand experience and I am sure you will find others with similar stories. I will NEVER EVER hook anything of value up to a substandard, lousy tolerance, shoddilly constructed, cold soldered, third world country built device like a power supply. I am scared to death of the crappy TVs we get thinking the same thing could happen with them, but I have never actually SEEN a TV power supply blow up before, or for that matter a clock radio, VCR etc......I have seen SEVERAL cheap stand alone supplies fry. I have also seen stereo power supplies blow like this, but with far less dramatic results. This is likely due to the lower power ratings on the outputs of those types of devices.

AMX
01-31-2006, 01:17 AM
Not being confrontational, but if there's a real documented safety issue with a certain class or brand of power supplies it needs to be raised to the proper authorities.


It is a common occurance....but so is a short at the cheap, crappy, junk, flimsy light socket that most common shop lamps or room lamps used to hold a 100watt or less bulb in.....UL loves them and passes them all day long.

they are in every house including brand new ones....look at those thin pot metal thread bases insulated with cardboard.....look at the wiring in a modern ceiling fan.,....


Fact is, so few people even have a power supply in their home, let alone use one hard, that it really never makes the radar of UL's problem devices.

I have never reported my failures....On the Dell computer thing I was so pissed I wanted to sue them. I AM surprised that isn't more common knowledge. With the right lawyer I bet that one would have made national news...


There are FAR more space heater and kitchen device horror stories for the UL to pursue rather than obscure power supply problems.....just not mainstream enough.

Go due your own test- go buy one and run it at 66% duty cycle for as long as it takes to pop. I bet it won't be long. Do it outside.

The Toolman
01-31-2006, 10:39 AM
My 30 amp Astron run for almost 48 hours straight this last weekend and hardly ever got warm. Most of the time there were 5-6 cars on the race track at any given time at my biz.

Ronnie

AMX
01-31-2006, 07:29 PM
It wasn't at heavy duty cycle.


That is the way they work....just fine then poof. Mine that turned into a fireplace wasn't warm either, nor was the device that was connected to it. Both were chugging along just fine and then snap. The Vista and Pyramids were just on and the devices hooked to them were off so there was surely no load on them.


Don't take my word for it....ask around. I heard all this stuff before myself and still habd to find out the hard way. I would never spend money for something as extravegant as a nice power supply or decent well configured computer. I always went cheap too like Astron and Dell.


Go check on a Ham forum and see what they tell you. Hams have blown up plenty of them.

AMX
01-31-2006, 07:34 PM
I just did a quick Yahoo search for Astron+power+supply=blown+up and got this


http://www.seits.org/features/pwrsup.htm


"There are two kinds of power supplies, those that have blown up, and those that will

Our popular Astrons for example are rated being able to supply only half of the current continuously that their specified for! That is, a twenty amp Astron can in reality supply only ten amps continuously.

POOR DESIGN
The first thing I did was remove the smoked parts and check out the rest after tracing out the circuit. After examining the design, I rapidly came to the conclusion that the designer had to have been on drugs."



http://www.seits.org/features/pwrsup.htm



Try astron sucks or power supply smoked or blown up and see what you get. Use yahoo not google.



It isn't just my opinion, it is common knowledge.



Another one: http://www.eham.net/forums/Elmers/29345?page=2


Read down a little where the guys says "why take a chance on burning your house down"


ALSO: http://www.harvardrepeater.org/pipermail/repeater/2003-October/000247.html

ALSO : GOOGLE GROUPS

I had an experience with an Astron where the pass transistor shorted. There is
no internal fuse between the capacitor and the over voltage SCR. The over
voltage circuit fires the SCR (presumably to blow the primary fuse) but it
simply opens because it can't handle the peak current of trying to discharge the
big capacitor. The result - about 28 volts to all the gear connected to the
Astron. I now modify the Astrons placing a large fuse (equal to maximum rating
of the supply) between the capacitor and the output/over voltage circuit. Astron
is not the only supply mfg that has this problem.


I found this stuff in just a few seconds....I am sure you can find more.

Nightshade
01-31-2006, 08:34 PM
Uh...how 'bout them Bears?!? :p

Like I said...gotta love power supply discussions. As for me....I won't have more than 4 lanes on a 4 x 8 table or 5 x 9 (at most). It's in my garage and the power supply will have to burn concrete while I'm there, which it won't....unless it does it spontaneously when disconnected! just kidding. ;)

Anyhow...I'm only racing with my kids and the odd relative/neighbor when they come by, and will only be out my shipping cost if it does decide to smoke.

Thanks for the links though...It'll be good reading for the next couple days.

AMX
01-31-2006, 09:40 PM
A decent Lab supply won't ignite like that....unless it is made in China, India or Korea

AfxToo
02-01-2006, 08:55 AM
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The Toolman
02-01-2006, 09:08 AM
I didn't have much info to go on when I first started this project so I just went with what Greg Braun sells. I didn't know how much I would need so I just got the biggest one he sells. I would do more investigating if I was doing it again though, but for now I am stuck with the 30 amp astron. I do turn the breaker off for it also when I leave the shop for the night.

Ronnie :o)

rodstrguy
02-01-2006, 07:53 PM
Though I have never had a Dell computer, I have had computers for over 20 years. Never has a power supply done anything other than make a puff of smoke and just stopped working. I work in the telecomunications field for the largest phone company and work with all kinds of power supplies and again have never seen one do anything other than smoke (fire is the largest fear for phone companies and they do everthing to make sure there is no fires). If for example computers or ham radio power supplies were starting house fires our wonderful TV news shows would be making us wait until the next ratings sweep with scare comercials about... "You may have a house burning down around you any time if you have own a... don't miss our 10 o'clock news next Thursday Night!"
Since I haven't heard our "scare you silly" media screaming that there are houses and hobby shops blazing across the country right at this moment because some crazy slot car guys are using inexpensive power supplies, I am guessing that you are either trying too hard to sell power supplies you have or are just writing things to "hear yourself talk", AMX.

Nightshade
02-01-2006, 11:30 PM
<whistling while I look around the room, thinking "what have I started?">


:rolleyes:

AfxToo
02-02-2006, 12:21 AM
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AMX
02-02-2006, 02:50 AM
I work in the telecomunications field for the largest phone company and work with all kinds of power supplies and again have never seen one do anything other than smoke


That is what high quality power supplies do when the blow....smoke at the worst.

Crap ones catch fire. The ones you work with in Telcom are far better engineered than these cheap 100-300 dollars POS'.

When the high dollar units go bad they usually have cap leaks that simply power down the unit, or will not allow it to turn on. They are far better protected at all stages of the circutry. They are designed to NOT go bad in a catostrophic fashion.

Read the links I posted about the holes burned right thru the circuit boards (which actually support fire in some of these things) and furthermore, the cheap supplies have transistors OUTSIDE the unit sunk onto heat sinks. When those go there is a fire source actually outside the chassis. A quick search will find more....fact is, almost everytime someone inquires about an Astron supply there are modifications suggested right away to make them last. This can't be dismissed as nonsense.


I really don't know what you have or have not experienced, but I myself have seen these events happen, know several people in multi state tech divisions for major pro and consumer component and computer repair that will laugh at these stories with me and add to them with their own tales, and am sure sooner of later someone else will chime in with a similar story.

I have only 1 lab supply that cost over $10,000 new that I would be willing to let someone "have" for 300 bucks....no sweat to me. I was from the begining just trying to help out.

It is like a guy offering a brand new Gulfstream for DC-3 money and the buyers still want the DC-3. I can't help that.


I have racks of pro grade stuff for myself....probably a lifetimes supply. Linear and switching. Those are keepers.


I will close with this...take one look at that $.99 meter on the front of an MG supply. It is pitiful. Like a childs toy. Look at the circuit board...it is rough, the traces pick right off like they are not even stuck to the board, components size and shape very from unit to unit of the same model. Plus there just isn't a whole lot of stuff in them. Look at all of the people claiming switch failures....come on....you should be able to turn on and off a switch 50,000 times without it breaking. Sorry, but those things are just plain cheap. So are Astrons. And the budget PC supplies are just as bad, and like I said, based on a multistate tech centers agreement, that is beyond question. Computers that have caught fire come through there all the time for warranty or if possible repair. Like I said, things that draw more tend to have more firey failures....space heaters, welders, high amp power supplies, big audio stuff, guitar amps, computers......probably in about that order

AMX
02-02-2006, 02:54 AM
Hey, peoples houses get hit by lightning and burn down everyday, but there aren't continuous news clips about it....once in a while a space heater story, or a bad extension cord (which burns down many houses every day if not every hour) or lightning fires hit the news.....

AfxToo
02-02-2006, 12:44 PM
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rodstrguy
02-02-2006, 01:00 PM
AFXTOO, You have to remember that 80 % of all statistics are made up... LOL!

The Toolman
01-16-2007, 09:10 PM
Well, my 30 amp adjustable Astron power supply I got from Gregg Braun(?) has run 7 days a week for 12-15 hrs. a day for almost 1 year now with no troubles whatsoever.

Somebody here told me my shop would probably burn down using an Astron. :tongue: I haven't run into a post yet on any forum where anybody's shop burnt down using this brand.

I'd buy another one in a minute if I had another track to setup.

Ronnie :)

Mike(^RacerX^)
01-16-2007, 10:46 PM
And once again,the dreaded power supply thread comes back yet again to HT to rear its ugly head. :wave: :hat:


Ronnie thanks for the info.

I havent burned my house down yet either.

Mike

The Toolman
01-16-2007, 10:56 PM
Well, I got such an a$$ eatin for buying an Astron last year I thought I'd come back with my .02 worth. LOL

Ronnie

Mike(^RacerX^)
01-16-2007, 11:43 PM
Well, I got such an a$$ eatin for buying an Astron last year I thought I'd come back with my .02 worth. LOL

Ronnie

Oh yeah!!!!!!!!!! I remember that now!!!! LOL

Mike