PowerMax Vbox X Transformer?

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Lone Gunman

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Yeah I already peeled back the wrapping on it but there's nothing to see under that but copper wire and that doesn't look like it's been hot. Maybe I need to pull that board up and look under it to see if there's a fuse of some kind under there. Will do that some time today.

UPDATE! Well, it's not the transformer after all. A look on the back that board shows some heat around one of those large black diode solder joints right next to the D8 on the top of that board. Shows some heat on top too once I looked a little closer. There's 4 of them in a line there and the solder joint is even loose. Looks like it horked up the board too so this one is definitely toast. :(
 
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Anole

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Pictures, please.
I'm still wondering about welded relay contacts..
..which could blow up the rectifiers.
(but that's just one theory)

I didn't think to disconnect the transformer secondary wirings and check for voltages.
That should have been the first step to confirm a bad transformer. :up
 

Lone Gunman

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Here ya go.



Notice the dark color at the base of that diode where the pencil is pointing. This diode is also loose on the board, which I'm going to "assume" is from the heat that was generated that melted the solder joints. That thing stinks to high heaven too. Electronics stuff doesn't run on electricity. They run on smoke!! Let the smoke out and electronics stuff will no longer work.

 

wallyhts

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I would try and replace the diode's and see what happens.

 

Joe DC

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I have the same positioner and had the transformer fail. Was unable to find a replacement. I did not replace the transformer but decided to purchase a "G Box" instead.
If you do find that the transformer is defunct you will need one with a dual secondary with 36 volt 2 amp winding and a 12 volt 100 ma winding. The diodes in question 1N5404 are rated 400v @ 3A silicon rectifiers in case they need replacement.
The photo of the rear of the circuit board hints of your problem. The solder joint your pencil is pointed at should not be in contact with the trace to the right. You might try to resolder the loose rectifiers and remove that solder short with the adjacent trace.
 

Lone Gunman

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Yeah well, I don't do solder that well. If I could arc weld it now I'd be good to go. ;) Ya gotta understand that I'm a gear head that happens to be a computer geek but even with computers no one ever fixes boards any more. Just replace them is all. Never did lean much about soldering anything but wires and stuff, nothing on these type boards.

I went ahead and ordered a Vbox 7 @ $37 to have as a spare as it was the cheapest one I could find. Cheapest Vbox X I saw was $50? If memory serves I only paid about $30 or so for the ones I have but that was a couple of years ago.
 

Anole

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Sep 22, 2005
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Send Joe the transformer, and me the (light weight) box! ;)
I'll check for welded contacts and other problems.
Would be good to know for next time.
 

Lone Gunman

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Send Joe the transformer, and me the (light weight) box! ;)
I'll check for welded contacts and other problems.
Would be good to know for next time.
Sorry but the transformer is horked up where I pulled the insulation off it trying to see if it had a fuse in it. If it was good before, it's not now.

Send me a PM with your address and I'll ship you that board. That will be pretty cheap as it will fit in a small package.
 

johnnynobody

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I know that this is an old thread but I found it when searching for a solution to my dead Powermax Vbox-X. Turns out that my transformer died even though it wasn't moving the dish. The transformer has an open primary. Since I had a spare Vbox-X I was able to confirm this. Anyway, it seems that the replacement transformer (Hammond 266K35-ND) mentioned in this thread seems rather light. The specs I saw stated that this transformer is rated at 3A on the secondary. I'm moving a 12 footer. Has anyone come across something else that'll do 5A? I wish I had a schematic for this thing. Anyway, the 266K35-ND costs about $45.00. I'm looking for something "heftier" but it may end up costing enough to justify buying the $175 ASC1.
 

Lone Gunman

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I know that this is an old thread but I found it when searching for a solution to my dead Powermax Vbox-X. Turns out that my transformer died even though it wasn't moving the dish. The transformer has an open primary.
Hummm, I've lost more than one Vbox X/7 from lightning strikes so it doesn't have to be doing anything to get zapped!

You didn't mention if you had checked the "thermal fused link" that's under the insulation on that transformer or not? THAT may be all that's wrong with it.

FYI, the newer Vbox 7 controllers, which basically have the same components on the main board as the Vbox X, have a 250v x 3.15a fuse in the secondary circuit and from what I've seen, most ALL the components in the 7 are the same as those in the X so not sure that 5a transformer would do you much good, ie, over powering the stuff on the circuit board.

There's a thread I started on here back about 4/6 months ago where I repaired several of those that might help you.
 

Titanium

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What is the maximum current draw on your system measured when lifting off the bottom of the arc? I once measured a Von Weiss actuator lifting a gigantic 5m fiberglass dish off the bottom of the arc (maybe 450-500lb lift) @ 3.5amps running. I would be surprised if your dish and actuator comes close to 2 amps under load.

With that said, the replacement transformer is almost 3/4 the cost of a new G/Vbox. Nothing wrong with super-sizing the transformer! If nothing else, it is a nice room warmer... LOL! If you do upgrade the transformer, also add heavier gauge wires from the PCB to the rear panel and wouldn't hurt to install a terminal strip rather than the spring loaded clips. The relays are are up for the task, but be sure to check the ratings on the other components in the path.
 
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johnnynobody

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Hummm, I've lost more than one Vbox X/7 from lightning strikes so it doesn't have to be doing anything to get zapped!

You didn't mention if you had checked the "thermal fused link" that's under the insulation on that transformer or not? THAT may be all that's wrong with it.

FYI, the newer Vbox 7 controllers, which basically have the same components on the main board as the Vbox X, have a 250v x 3.15a fuse in the secondary circuit and from what I've seen, most ALL the components in the 7 are the same as those in the X so not sure that 5a transformer would do you much good, ie, over powering the stuff on the circuit board.

There's a thread I started on here back about 4/6 months ago where I repaired several of those that might help you.
The fusible link is open. But, so is the transformer itself. Rather than replace the transformer I'll see if I can find another Gbox or Vbox. If I can't find a new one I'll consider the ASC1 even though that's more money than I want to spend. I saw a Superjack positioner listed at Amazon but I'll have to see if I can find some reviews on it.
 

johnnynobody

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I got this transformer today. I should've looked at the specs more closely. I knew as soon as I removed the package from the lockbox that something was wrong because it was much heavier than expected. It is not a direct replacement for the original transformer - not even close. I don't think I'be able to mount this in the existing enclosure. I should've spent the money for a new positioner. Oh well, live and learn.
 

Titanium

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I didn't realize that you were going to try and swap the transformers. Sorry, if I had known, would have pointed out the size dimensions. BTW, it is even to tall to fit in the ASC1 case (and the ASC1 case is LARGE)! :eeek

Why not put the transformer in a separate enclosure and run the wires in a braided sleeve or split loom?
 

Magic Static

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I was looking for one that would fit in an ASC1 case. That was the big one @175 VA. The next size down 130 VA and won't fit the ASC1 case but the 80 VA one will. Still too big for a VBox case. :(
 
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