AC/DC & POWERSTATION KIT BUILD THREAD

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diylan
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Joined: Mon Sep 20, 2010 5:40 am

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by diylan »

Hey Joe,

I just put the powerstation kit together (w/ 4 amp bridge rectifier) and I'm getting some very odd voltages... I think. The power supply I'm using is 2x18 and I'm trying to achieve +/- 16v rails to run in parallel and a 48v for phantom. Using the doubler jumper, I'm getting 7.3vdc on the positives (no adjustment), -16.9vdc on the negatives (no adjustment), and the highest I've been able to adjust the phantom has been about 33vdc. I started w/ the phantom, then began to realize things were a little weird.

So far I have not connected the corresponding outputs to run parallel. Also when connected, where the transformer secondaries connect to the board each reads 7.3vac.

Any thoughts? Thanks!

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Joe Malone
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by Joe Malone »

diylan wrote:Hey Joe,

I just put the powerstation kit together (w/ 4 amp bridge rectifier) and I'm getting some very odd voltages... I think. The power supply I'm using is 2x18 and I'm trying to achieve +/- 16v rails to run in parallel and a 48v for phantom. Using the doubler jumper, I'm getting 7.3vdc on the positives (no adjustment), -16.9vdc on the negatives (no adjustment), and the highest I've been able to adjust the phantom has been about 33vdc. I started w/ the phantom, then began to realize things were a little weird.

So far I have not connected the corresponding outputs to run parallel. Also when connected, where the transformer secondaries connect to the board each reads 7.3vac.

Any thoughts? Thanks!
Because you are only getting 7.3vac going into the Powerstation PCB you need to check you have the 2 x 18vac transformer with the mains side wired correct for your mains voltage including the correct phasing for the primary and secondary windings? If there is a picture of the windings on the transformer side connect the center 2 wires to 0v on the PCB and each outer wire to a AC in each. The 0v on the transformer side of the powerstation is the terminal closest to the front edge of the PCB NOT the center terminal. Since it is 18vac you will need to set tripler to get 48v. I would also check that you do not have any shorts between solder pads where the 6A bridge solders in as the spacing there is tight. Make sure you turn all trim pots back to there rough center positions (back about 10 full turns) if you have turned them fully up.

As always if you cannot find the problem email me large in focus well lit macro on photo's of the top and bottom of the PCB and your wiring and transformer info and I should be able to get you going quickly.
Joe :-)
JLM Audio
Capturing Audio without Injury

diylan
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Joined: Mon Sep 20, 2010 5:40 am

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by diylan »

Thanks for the quick reply Joe! First off, my mistake with the jumper, it was on the tripler, and typo on the amperage for the rectifier as well. oops :mrgreen:

As far as I can tell, all of the solder points look good; I double checked around the rectifier. I'm now starting to suspect that there may be an issue with the transformer I've got. It is supposed to be 18 - 18 in parallel, 36 - 0 - 36 in series, and I'm in the US so I'm looking at parallel hookups on both sides. As far as I can tell it was hooked up correctly, but just for the hell of it, I wired it up in series and the transformer outputs were reading about 20vac... not quite the 36 that they should. At least the phantom was reading pretty close to 48vdc!

Everywhere printed on the transformer, and on the box it came in, it's telling me it should be outputting 18 or 36, but the thing doesn't seem to want to. It's made by Triad... do they have a reputation for stuff like this? The only thing I can think of is that the voltage comes in pretty hot at my house, about 120vdc instead of 115, that would just increase the voltage of the secondaries though... right?

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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by Joe Malone »

diylan wrote:Thanks for the quick reply Joe! First off, my mistake with the jumper, it was on the tripler, and typo on the amperage for the rectifier as well. oops :mrgreen:
OK
As far as I can tell, all of the solder points look good; I double checked around the rectifier. I'm now starting to suspect that there may be an issue with the transformer I've got. It is supposed to be 18 - 18 in parallel, 36 - 0 - 36 in series, and I'm in the US so I'm looking at parallel hookups on both sides. As far as I can tell it was hooked up correctly, but just for the hell of it, I wired it up in series and the transformer outputs were reading about 20vac... not quite the 36 that they should. At least the phantom was reading pretty close to 48vdc!
Ok you have this wrong. They should not read 36v except from end to end when the 2 windings are wired together in series. Each winding should always be 18vac or in your high voltage area 20vac each.
Everywhere printed on the transformer, and on the box it came in, it's telling me it should be outputting 18 or 36, but the thing doesn't seem to want to. It's made by Triad... do they have a reputation for stuff like this? The only thing I can think of is that the voltage comes in pretty hot at my house, about 120vdc instead of 115, that would just increase the voltage of the secondaries though... right?
You do not want the 18vac secondaries in parellel. The transformer needs to be wired in series so there is a centre tap this will make 18vac - 0v - 18vac (making 36v centre tapped or 40vac in your case) which is what you want. The centre tap needs to go to the powerstation 0v at the transformer end and each 18vac needs to go to a AC in on the powerstation each,

It sound like at the moment you are running the Powerstation floating with nothing to the powerstation 0v from the transformer which will leave the powerstation floating as there is no 0v ground reference. With only 18vac to both AC in you will only get +/-12vdc = 24vdc total but with no 0v reference this will float up and down and be why you had +7.8 and -16v = 24vdc total.

Do not forget to wind back the trim pots to half way before powering up after connnecting the transformer correctly.
Joe :-)
JLM Audio
Capturing Audio without Injury

diylan
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by diylan »

:oops: Oops! Well that was it, everything is working great now.
Thanks Joe!

tdog
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Joined: Mon Oct 11, 2010 12:43 am

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by tdog »

hi

is it possible to drop the +48v rail to 12v?

Thanks, tom

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Joe Malone
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by Joe Malone »

tdog wrote:hi

is it possible to drop the +48v rail to 12v?

Thanks, tom
Yes easy one. Link over C1 and C2 positions and link center pad to D.
Works the same on AC/DC or Powerstation. See photo below.

Image
Joe :-)
JLM Audio
Capturing Audio without Injury

tdog
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by tdog »

cheers, that's brilliant.

tom

SRBSquash
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by SRBSquash »

Hello,

I am new to DIY, and am building an AC/DC kit. I am getting no DCV out of the supply at all. I have 22VAC going in, but am not sure the best way to trouble shoot this. I have confirmed all resitor values, and locations, and all components are in the proper locations. I cannot see any bad solder point on the underside and cannot see any bridges. I have looked this over for hours, and am not sure where to go from here.

Thanks in advance for any input you may have that can help.

Josh

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Joe Malone
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by Joe Malone »

SRBSquash wrote:Hello,

I am new to DIY, and am building an AC/DC kit. I am getting no DCV out of the supply at all. I have 22VAC going in, but am not sure the best way to trouble shoot this. I have confirmed all resitor values, and locations, and all components are in the proper locations. I cannot see any bad solder point on the underside and cannot see any bridges. I have looked this over for hours, and am not sure where to go from here.

Thanks in advance for any input you may have that can help.

Josh
Ok first what voltage outs are you going to need? +/-? and 48v or +? and 48v?
Do you have the 22vac wired to one AC in and 0v on the left hand side of the PCB?

As always if completely not sure email me large macro on well lit in focus photo's of your wiring and top and bottom of the AC/DC PCB which will help me get you going quickly.
Joe :-)
JLM Audio
Capturing Audio without Injury

kante1603
Posts: 86
Joined: Wed Jan 20, 2010 6:12 pm

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by kante1603 »

Hi Joe,
I have built some of your PSUs before,but now I have a problem with an AC/DC.The negative rail is not working.
I use a small 2 x 18v(2x290mA) torroid.center tapped reading fine about 21 Volts AC each side.
I did the mod. with the 2 wire links and doubbler to "d" to achive +12v DC on V2.
Both positive rails are working (+18v on V1 and +12v on V2),but the negative is not.Also the torroid runs hot very fast.
I changed the 337 and trimmer,but it remains the same.The neg.rail follows the trimm pot in a range of -0,04 to -0.74 Volts,and-after cooling down- I measured no (rectified) DC at the 337.
I fear that i will destroy the transformer when I go on measuring because it is getting hot pretty fast!

Any help would be appreciated!

Thank you very much Joe,

best regards from germany,

Udo.

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Joe Malone
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Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by Joe Malone »

kante1603 wrote:Hi Joe,
I have built some of your PSUs before,but now I have a problem with an AC/DC.The negative rail is not working.
I use a small 2 x 18v(2x290mA) torroid.center tapped reading fine about 21 Volts AC each side.
I did the mod. with the 2 wire links and doubbler to "d" to achive +12v DC on V2.
Both positive rails are working (+18v on V1 and +12v on V2),but the negative is not.Also the torroid runs hot very fast.
I changed the 337 and trimmer,but it remains the same.The neg.rail follows the trimm pot in a range of -0,04 to -0.74 Volts,and-after cooling down- I measured no (rectified) DC at the 337.
I fear that i will destroy the transformer when I go on measuring because it is getting hot pretty fast!

Any help would be appreciated!

Thank you very much Joe,

best regards from germany,

Udo.
HI Udo
Easy one. Remove the Doubler jumper and it will all work. When using a centre tap transformer and no voltage doubler no jumper should be fitted to the doubler ot tripler or it will short the negative rail out.
Joe :-)
JLM Audio
Capturing Audio without Injury

kante1603
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Joined: Wed Jan 20, 2010 6:12 pm

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by kante1603 »

Thank you so much Joe-that was the fastest "fix" i have ever done in my life!!!

It is after midnight here so i got a little tired and was loosing concentration but thought of a short somewhere :lol:
Now i must not dream of it-everything set up and working fine-cool!

Have a nice weekend and thank you again and again and again and again and again and again and again and again and again ......

Best,

Udo.

P.S.:...will buy more of them-and again and again and again ..... :D

chunger
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Joined: Wed Nov 17, 2010 7:24 pm

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by chunger »

A bit of an electronics newb here. . . I'm trying to get my powerstation to power a few GDIY 51x modules. . .

Image

I'm using a 12V+12V transformer (Avel Y236102), and I believe I have it wired in series for 24V. . . . outer leads to AC, and center taps both going to 0V on the A/C side of the board.

The +V1 and -V1 are working fine and set to +-16V.

The 48V adjusts, but only goes up to 37.4V (set to doubler).

+V2 currently reads 0 volts
-V2 reads -18.3V and does not adjust on the trim pot

Help would be appreciated. I have a spare kit on hand if necessary.

chunger
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Joined: Wed Nov 17, 2010 7:24 pm

Re: AC/DC & POWERSTATION KIT BUILD THREAD

Post by chunger »

wow. . . ghost town around here. . . I guess everyone is on vacation.

Well, figured out my problem.

-V2 was actually working, I just needed to crank counter-clockwise on the trimmer a bit to get the trimmer into it's operating range. So, my only problem was +V2 not functioning. A friend dropped by and helped me trace the problem because I'm not very electronics literate. He determined I was good to go all the way up to the output terminal, so I removed the PCB from the back plate on my assembly to investigate.

Image

And found this. . . just like he said.

Image

Now, the powerstation was working right, but 18.3 volts was my max on the +-V1 and +-V2 rails and 37V my max on the 48V rail, so I figured my toroid was feeding 12V. . . not the 24V I wanted. Also, there were some serious discrepancies between the available schematic (Version 2) and the actual (Version 3) PCB.

At any rate, I wired my mains as such with one of the "AC" lugs not connected.

Image

And I was able to get everything up and running and trimmed out to my desired voltages +-16V, +-24V, 48V.

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