Need help for broken Transporter

[Craig]

I think Craig may have removed the insulation sheet. To be honest, it's probably not a good idea. It's the only thing between the high-voltage rails and the metal case, besides a little bit of air gap.

No I didn't remove that, they must have added that after the initial run of them. Does it run all the way front to back? Is it just glued down?

Craig

[JoeMuc2009]

Sorry Craig, didn't want to blame anybody. It's all the more interesting that Slimdevices put the sheet in later.
It's a really thick plastic sheet which is partly glued down with adhesive strips. Quite pesky, too, as it is bent upwards on the right flank to cover the sides of the PCBs also, but the material is so springy that it pushes firmly outwards which makes it a real pain in the butt to put the top lid back on. Bending it the opposite direction to make reassembly easier causes it to rupture, probably needs some warming up before any attempt to bend it.
Anyway, if yours is working as it should, there is probably no need to do anything about it. Are you the first owner of this Transporter?

[Craig]

Interesting, I did actually consider putting some insulation under my new psu but figured that if it was going to short then it would short on the mounting posts anyway.

Yes I'm the original owner and I don't think it's ever been opened previously.

I ordered it directly from Slim Devices when they were first announced and they shipped it to me in the UK so it must be one of the oldest ones around.

Craig

[Fizbin]

The later units are UL approved. I guess that's why some changes were made.

[gclpc]

I have also had the same problems with one of my Transporters stopping working. Thanks to all of the great help on this forum, I swapped out the PS board to check. Sure enough, I was working in minutes. I really appreciate the assistance.

Greg

[Owen Smith]

When replacing the display PSU with a matching one, has anyone tried adding heatsinks to the power transistors? There is stuff about putting longer legs on the capacitors and such like, but wouldn't it be better to get the heat out of the board in the first place?

[Owen Smith]

After many years continuous service my Transporter was unused for five month while we renovated the house. Two weeks after getting it running again it blew the mains fuse.

I diagnosed the fault to the 5V psu before discovering this thread, I nearly went down the Rapid Electronics route for a replacement but realised that it's the same old design and would probably fail again somewhere down the road so I set about finding a better replacement.

I ended up making a direct drop in replacement using an encapsulated psu that is rated at 20W and 4A. It also has an MTBF (Mean Time Between Failure) of 54 years so hopefully it should last a while.

If anyone else is interested, I should be able to build you one for about £20 + postage.

Craig

Is the offer to build one of these PSUs as a drop in replacement still valid? I'm in the UK so postage shouldn't be an issue.

I'm thinking of buying a Transporter but don't fancy running it with a PSU known for getting too hot. Overrating the current by a factor of 2 is my usual margin eg. when buying LED drivers for low voltage LED bulbs.

[JoeMuc2009]

Well, heatsinks will drop the temperature a bit, but capacitors still shouldn't be too close. Alternatively, one could put a fan in there and power it by the +5V output but this is nothing any enthusiast would consider due to noise (potentially including side-effects on the analog outputs). So I personally would still prefer to put the capacitors off the board in a safe spot. The transistors are becoming hot, granted, but they are not overloaded, and not becoming desoldered by the self-generated heat. At least that's nothing I have ever seen on any of the power supplies in my repairs.
Oh, and tight space on the PSU board might also prevent the use of heatsinks...

[Owen Smith]

Well, heatsinks will drop the temperature a bit, but capacitors still shouldn't be too close. Alternatively, one could put a fan in there and power it by the +5V output but this is nothing any enthusiast would consider due to noise (potentially including side-effects on the analog outputs). So I personally would still prefer to put the capacitors off the board in a safe spot. The transistors are becoming hot, granted, but they are not overloaded, and not becoming desoldered by the self-generated heat. At least that's nothing I have ever seen on any of the power supplies in my repairs.
Oh, and tight space on the PSU board might also prevent the use of heatsinks...

Personally I prefer to just overrate this sort of supply by a factor of 2, I do that for low voltage lighting LED drivers. Everything runs a lot cooler then. Shame there isn't an off the shelf drop in replacement rated at 4 amps.

[Fizbin]

Just buy the original. (Or buy two) They last 7-10 years.

https://www.rapidonline.com/powerpax...c-2-3a-85-2251