DMS Vbox 7 Transformer?

[Lone Gunman]

Well, as if lightning wasn't creating enough scrap around here, the other night my Vbox 7 mover on the Unimesh system took a dump for no apparent reason?? It was working fine earlier in the evening when I recorded some stuff but later that night it was toast. After doing some checking the next day I found that the primary coil in the transformer is open so I guess that's why there's no voltage shown on the outputs.

So I connected up a 12volt battery to the motor wires inside the house and had the Wife run it while I was looking at the dish and it worked fine in both directions and was as quiet as a church mouse. So the Von Weise mover doesn't appear to be a problem.

Ennywho, was wondering if by chance anyone might have a good transformer laying around that they'd be willing to sell me?

 

[KE4EST]

Let me do some digging around.

 

[Magic Static]

I would like to find a source for that transformer too. I've done some searching but never found anything with those specs. If it's the old style VBox 7 with a metal I/O plate the transformer has a thermal fuse just under the outer wrappings. I have a bunch of those fuses. I've fixed my VBox X a couple of times.

 

[wvman]

Well, as if lightning wasn't creating enough scrap around here, the other night my Vbox 7 mover on the Unimesh system took a dump for no apparent reason?? It was working fine earlier in the evening when I recorded some stuff but later that night it was toast. After doing some checking the next day I found that the primary coil in the transformer is open so I guess that's why there's no voltage shown on the outputs.

So I connected up a 12volt battery to the motor wires inside the house and had the Wife run it while I was looking at the dish and it worked fine in both directions and was as quiet as a church mouse. So the Von Weise mover doesn't appear to be a problem.

Ennywho, was wondering if by chance anyone might have a good transformer laying around that they'd be willing to sell me?

Lone, if no one in here has any luck finding one, check out this website. I've bought several transformers off them for various applications. http://www.jameco.com They have like 15 pages of nothing but transformers. While you're at it, you may want to check the diodes in the rectifier section. I've seen them go out taking the power transformer with them. It would be nice though if someone in here has one out of a similar unit. It would eliminate having to spec out one online at Jameco.

 

[Magic Static]

Lone, if no one in here has any luck finding one, check out this website. I've bought several transformers off them for various applications. http://www.jameco.com They have like 15 pages of nothing but transformers. While you're at it, you may want to check the diodes in the rectifier section. I've seen them go out taking the power transformer with them. It would be nice though if someone in here has one out of a similar unit. It would eliminate having to spec out one online at Jameco.

I've checked that site for this transformer too with no luck

 

[Lone Gunman]

I would like to find a source for that transformer too. I've done some searching but never found anything with those specs. If it's the old style VBox 7 with a metal I/O plate the transformer has a thermal fuse just under the outer wrappings. I have a bunch of those fuses. I've fixed my VBox X a couple of times.

Yeah Magic, the old Powermax Vbox X controllers did have a fuse link in them but this one doesn't, at least not that I can find anyway. I peeled the insulation up on it but there's nothing there but windings.

I've got a couple of those Vbox X controllers that are trash and may have a transformer that's good but I'm not sure which wire goes where and on the Vbox X they are soldered to the main board. The Vbox 7 has a 4 pin connector on the board that the transformer is connected to.

KE4EST sold some of these at one time and he says he might have one so lets wait and see what he comes up with.

 

[Lone Gunman]

OK guys, remember back a few weeks ago I made the statement that I wasn't a "electronics" guy?

Well, after more digging in the insulation it turns out that this transformer DOES have a thermal fuse in it and not only that but the main fuse on the board itself was blown as well. So I might have more problems than just that thermal fuse being open. It's a Thermal Cutoff Fuse 2A 250V 2 Pin 125 C Y30.

Now that I think about it the position count was kinda slow changing right before it blew so it may have other problems as well.

I think I'll just "rig" a temporary inline 2a fuse on the primary transformer circuit and then connect it up to see if it will work like that before I go spending more money on it not knowing WTF I'm doing.

 

[Magic Static]

I put a fast blow 2A fuse on the power to the transformer but it still took out the thermal fuse first. Probably best protection for that kind of transformer. The best thing I did for mine was to take it out of its plastic case and put it in a metal box which gives it a heatsink.

 

[FTA4PA]

OK guys, remember back a few weeks ago I made the statement that I wasn't a "electronics" guy?

Well, after more digging in the insulation it turns out that this transformer DOES have a thermal fuse in it and not only that but the main fuse on the board itself was blown as well. So I might have more problems than just that thermal fuse being open. It's a Thermal Cutoff Fuse 2A 250V 2 Pin 125 C Y30.

Now that I think about it the position count was kinda slow changing right before it blew so it may have other problems as well.

I think I'll just "rig" a temporary inline 2a fuse on the primary transformer circuit and then connect it up to see if it will work like that before I go spending more money on it not knowing WTF I'm doing.

If it works with the temporary fuse and you want to repair it permanently make sure you use the same or a similiar part. The insurance company likely won't pay any claims if the original safety features have been defeated or altered. Found these on Amazon: 250V 2A 125°C Thermal Fuse

 

[FaT Air]

If the transformers internal thermal fuse is blowing, sometimes without taking the mains fuse, more than likely the culprit is a shorted turn or two in the transformer. Shorted turns = high amps and heat.
A long time ago, I had this happen and had no direct replacement. I put a voltage compatible transformer in an external box with a line fuse and ran the secondary low voltage lines to the originals ckt bd.
Check the rectifiers, regulators, and caps also.

 

[wvman]

I've checked that site for this transformer too with no luck

Magic Too bad. Hope you locate one.

 

[Lone Gunman]

Check the rectifiers, regulators, and caps also.

You're kidding me, right? What part of "electronically challenged" did you not understand? I'm a "gear head" so that ought to explain it a little better. In my lifetime I've built two race cars from the frame up but the electronics experience I have has been basically "plug and play", ie, if I plug it in and it works that's good. It it doesn't, then it's broken!

Got "HoneyDo" stuff to take care of so I doubt I'll have much time to hork with it today.

To be continued:

 

[Lone Gunman]

OK so I got this thing "rigged" up on my desk and connected to an old Super Jack late last night. It powers on and will run the actuator but the transformer gets hot as a pistol in pretty short order? I didn't put a fuse in the line but instead just kept my had on the plug and pulled it as soon as I saw a whiff of smoke off the primary coil. Did that several times after allowing it to cool off between runs and it still works this morning.

So does that mean that the primary coil in the transformer is shorted inside? KE4EST has a transformer he's going to sell me if this is the problem.

Thanks guys!

 

[Magic Static]

I think the thermal fuse is set to 82°C, and that would be hot to touch. But if you're seeing smoke, there is no way to put the smoke back in the transformer so it's toast.

 

[Lone Gunman]

I think the thermal fuse is set to 82°C, and that would be hot to touch. But if you're seeing smoke, there is no way to put the smoke back in the transformer so it's toast.

Well, I didn't let ALL the smoke out because it was still working this AM. Just didn't have it plugged up over about 30 seconds at a time.

RE: Thermal Fuse? This one is marked 2A 125*c so that's 257* F and would burn you. I think my IR heat gun showed like 190* or so just after I unplugged it.

So do you think the transformer from KE4EST would fix it or is there something else that could be causing this?

 

[Magic Static]

Well, I didn't let ALL the smoke out because it was still working this AM. Just didn't have it plugged up over about 30 seconds at a time.

RE: Thermal Fuse? This one is marked 2A 125*c so that's 257* F and would burn you. I think my IR heat gun showed like 190* or so just after I unplugged it.

So do you think the transformer from KE4EST would fix it or is there something else that could be causing this?

Kind of a "chicken or egg" question. But if you can't find a problem elsewhere like binding in the dish mount or wear in the actuator causing issues or a corroded electrical connection than I would go for the transformer.

 

[FaT Air]

I'd say there are shorted turns in that "HOT" transformer.
As long as it's got the voltages, and physically fits, KE4EST's transformer will most likely work.
Once it's operating again, I'd monitor the output voltage and current while running the actuator all the way across the arc. Should be a max of one amp (or there about) unless lifting it off one end of the arc. Even there it should only go to about 2.5 for a few seconds only. (I personally like a 'old school' analog meter for these current readings. No digital 'lag' in readings)

Wanna let ALL the smoke out of it. Run a heavy extension cord to it as it lies on good sized patch of gravel. Plug it in. I'd put a fuse inline, at the current rating of the extension cord, so as to not 'smoke' that. Have a fire extinguisher 'handy'.
(I'm aware that's 'bad advice' so no warnings necessary)

 

[Lone Gunman]

Magic this thing has been connected to two different actuators. The Von Weise is on that's Unimesh dish and the Super Jack that's here in the shop laying on my desk so at this point I don't think either of those is the problem since it appears to be doing the same thing on both. I did run the dish with a 12v battery and the Von Weise was so quiet I couldn't hear it running. But then again, I do wear hearing aids.

Phat, yeah I'd bet that would be a pretty good light show, hey. Especially if I did it at night.

Think I'll go ahead and spring for that transformer that KE4EST has already boxed up and ready to ship.

Thanks for the reply guys.

 

[Lone Gunman]

Anyone know what the output voltages on the secondary coil of these Vbox 7 controllers is suppose to be? There are two pairs of wires, each pair a different color, ie, red pair and black pair. I'm going to "assume" that one pair is up around 35v for the actuator motor and the other pair "should" be a lower voltage for the control circuit? I need to know what these two are suppose to be.

Reason I ask is because I have a couple of "expired" WSI Vbox X controllers here that have various problems but I don't think the transformers are bad. I'm thinking that I "might" be able to use one of those if this happens again since the main boards in them look so similar.

Yup, I'm venturing into uncharted territory!

 

[Magic Static]

One is 36v AC and the other is 18v AC