Note from StatFreak: Per Uniman, it is important to note that the specific parts and repairs listed in these posts apply to the PSs being worked on here but not all Uni PSs because there were so many variations. Bware's and Joeys' power supplies were Yellow Dot. Diecaster might have had a Red or Green Dot.bware
« Reply #34 on: January 09, 2006, 09:02:58 PM »
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Ive got the exact same one (
PS) as the one shown in Joeylc's pics except mine does not have the tower-4 PCB.
Mine has a '22000uF 16WV CE 85 deg C Negative Black' capacitor, the manufacture is 'Nickicon'.
The 5V regulator, mounted on the heatsink on the top of the P/Supply is a 'UA78H05SC' batch no 'F 8430' and 'Hong Kong' writen on it.
Joeylc with respect to the P/Supply being dead as a nail, it seems that there is a common problem with it, I'd perform the following:
1. Check all the Fuses, especially the two 'INPUT 3A' ones .
2. Check the ON/OFF switch.
2. Check if your input supply 110VAC or 240VAC arrives at the Transformers input coil. If not check wiring and the 'Noise Filter'.
3. Check the AC voltages ie 24V AC and 9.5V AC outputs, wrt to the 0VAC terminals of the transformer.
4. Check your 5V DC output on the Molex Connector, NOTE: Use the DC earth.
Hope this helps,
regards
diecaster
« Reply #36 on: January 10, 2006, 01:12:53 PM »
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My mistake also on the 22000 cap, I'm looking at the cap that is soldered across 2 legs of one of the bridge rectifiers.
I've made a list of components that I believe are the key to rebuilding my unit. The total cost is under $20.00 US
Below is a link to one of the best electronic part suppliers you can find. They have a great search engine that cross references various manufacturers part numbers.
http://www.mouser.comBelow is a list that I hope is correct to rebuild the Universal power supply based on components that normally fail.
1) 526-NTE5314 ( 400v 8 amp bridge rectifiers) QTY 3
2) 627-S2VB60 ( 200v 2 amp bridge rectifier) QTY 1
3) 647-UVR1H221MPA ( 220 uf 50v cap) QTY 1..............This is the one swelled and over heated on my power supply
4) 511-LM 323K ( 5v voltage regulator) QTY 1 This is a guess, but the specs seem correct
This list is using all the Mouser part numbers. I will be ordering shortly. I plan on changing everything but the voltage regulator on my rebuild, that's a spare.
Feel free to correct me if you find any discrepancies in my list.
Mark
Cactusjack
« Reply #37 on: January 10, 2006, 01:41:11 PM »
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4) 511-LM 323K ( 5v voltage regulator) QTY 1 This is a guess, but the specs seem correct
Feel free to correct me if you find any discrepancies in my list.
Mark
If the LM323K is being suggested as a replacement for the 78H05 (or Joey's LT1003) it is wrong. The LM323K is a 3 Amp 5 Volt Regulator and the 78H05K is a 5 Amp 5 Volt Regulator.
You can also use a NTE932 as a replacement for the 78H05/LT1003.
CJ
Cactusjack
« Reply #44 on: January 11, 2006, 09:16:05 AM »
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My mistake also on the 22000 cap, I'm looking at the cap that is soldered across 2 legs of one of the bridge rectifiers.
My Rectifiers
do not have this 220 uf 50V capacitor installed. My assumption is that this is only a 'smoothing' capacitor mounted across the AC Input of the rectifier to smooth or prevent AC surges from the transformer. As Mine is a 240 AC Input transformer, it sounds like this "Mod" is only relevant for the 110V AC Input transformers.
regards
I doubt a 220 microfarad cap would be place across the AC terminals, especially if its an Electrolytic cap. My guess is its probably across + and - of the bridge (don't see it in any pictures). In the old days of Linear power supplies (which this appears to be since it uses a linear 5 volt regulator), it wasn't that uncommon to make a "band-aid" fix to a power supply when a large value cap (like the 22,000ufd you have mentioned) starts to reduce its overall microfarads, by adding another cap across it to replenish the capacitance (in this case, filtering).
And like was mentioned, it might have been an issue when going from 220 to 110 VAC but it should be since a properly tapped transformer will deliver the same on the secondary windings. HOWEVER, it might have been an issue if it were designed to run at 60 Hertz, but was instead running at 50 Hertz. In this case, there would be more time between AC waves that the filter caps had to hold their charge.
But 220ufd is small in comparison to 22,000ufd. Does any one know what voltage portion of the power supply this bridge/cap combo feeds?
Of course, I could be totally wrong here.
CJ
Cactusjack
« Reply #45 on: January 11, 2006, 09:25:36 AM »
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Does anyone know the rating of the bridge rectifiers in this type of power supply?
Overall, Bridge rectifiers are not all that exotic. There are basically only a few packages and the package usually determines the maximum Amperage rating. A picture would probably be all that is needed to tell you the amperage rating.
The large Black or Silver bricks with a bolt down the center are usually rated at 25 AMPS with some being 35 AMPS. This 25 or 35 is often part of the part number. The medium size black epoxy squares also with a center screw hole are usually rated at about 8 amps but there were some more exotic ones that were good for 12 AMPS. The smaller black "rectangles" (with all 4 leads pointing down in one row) are usally 4 AMPS. The small little round ones (smaller than a US Dime in diameter) are only 2 amps. The are also some small rectangular ones that are only rated at 2 amps also.
As to voltage, it just depends on what AC is going in to it. Since someone has mentioned 9.5VAC and 24VAC. In both cases, a 50 Volt bridge will do the job well.
CJ
Cactusjack
« Reply #47 on: January 11, 2006, 05:30:38 PM »
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As I recall, the 78H05K was also disconntinued back in the 90's. So I could see how the NTE/ECG stock would have diminished by now.
I don't get any hits on the net other than people that might want to sell you their entire inventory.
It is possible, that the 3 amp part may work depending on how many TTL ICs are on all the boards. But more than likely, the LM323K will either run hot or not put out enough 5 volts.
One possible solution would be to buy a small 5 volt only switching power supply to install in place of the entire 5 volt regulator circuit.
http://www.mpja.com/productview.asp?product=15061+PSOR the #23E101 on this page:
http://www.alltronics.com/power_sources.htmOr this one from Mouser.com:
418-CFM40S050
CJ
bware
« Reply #51 on: January 12, 2006, 09:43:11 PM »
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Hi Mark,
Sorry for the delay.
1. Wrt:
the 220 uf cap is across the + and - of one of the bridge rectifiers and may have been a mod for the voltage we are running.
If you say its across the output, i.e. the + and - terminals, of the Bridge then its a "protection" capacitor, it's function is to protect the Bridge and the circuit it feeds, if the capacitor, as shown in the wiring i.e 22000uf cap for example, goes open circuit. These big electrolytic caps, called "Paper Capacitors" as the insulation between the plates within the caps where made from paper. These Paper Caps are prone to go open circuit. I'll leave the small 220 uf cap across the Bridge. In fact it might be a good idea for me to mount one also. PLEASE TAKE A PIC of this cap this weekend sothat I can see which Bridge is affected.
2. Wrt your question, I would start a new thread called 'Universal Pty Ltd Machine Parts Source Data Listing' or something to that effect, as I feel that info will not be made visable to some as this thread has 'Stars & Stripes' in it, so people might not look here for that info, if they have another Universal Machine. You'll notice Ive placed the Pty Ltd to prevent the word Universal meaning 'universal' in general.
good luck,
regards
PS: Please take Pics this weekend, will be much appreciated.
bware
« Reply #77 on: February 09, 2006, 09:33:31 AM »
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Hi All,
Ive modified the power supply section to meet my 'Yellow Dot' Power Supply for anyone interested.
regards
PS Very quiet on this thread lately?