CTEK D250s dual repair needed

Allan B. might have been able to help you Phil, but he's just left on a trip into the remote areas of the Centre.

Bin the Ctek and get a Redarc 1225D. A new model that is simple to set up, with no relays or trigger wires required.

Bob

When you fry a Ctek it stays fried , it is the same as trying to unfry a chicken egg ,

If you know it is a diode and whch way around the band at the end was, then replace it with a high voltage diode of similar size. The sizes are an indication of the current rating, bigger won't hurt.
However, if a small diode, ie, glass envelope, it could be a Zener diode and knowing the voltage then would be required for correct operation.
If the unit is old and had plenty of use, the electroylic capacitors may be the cause of the diode failure because the circuits action may be incorrect and switching of semiconductors has drawn more than usual amps through the diode.
I recently repaired two swichmode power supplies where electrolytic capacitors had become ineffective. One did require a diode and electro's replaced. Both now work again. The concepts are quite similar in switching DC DC units.

Ctek won't give you any info, they want to sell a new one to you, not have you repair the one you have. They will only say, return to maker for service/repairs.

Thanks for the prompt replies!

I managed to get to a mate's place and pulled his apart. The diode (D9) is a 5pex, which is a TVS type 5.0SMDJ22A.

Element14 has them but ill have to wait a week as they are coming from UK.....



Thanks again peeps

Hi Phil
Today I blew my D250S fuse F1 and probably the diode D13 too. I stupidly connected the battery incorrectly in my haste. Now I can't figure how to remove the 30A fuse without removing the board, thought the blade would just pull out.
Any help please and my hand is up for a diode if you still have some.
cheers
Phil

edit: Looks like D13 is a different type to D9. Still can't figure why the blade fuse doesn't come out. Didn't really want to remove the board if I don't need to.

The fuse is soldered to the board..... Need to scrape off the waterproof wax first then you can free up the fuse...

Good luck with it.

Cheers
Phil

Thanks Phil, feared as much.You'd think they would make the fuse easy to get at rather than having to pull the whole thing apart. The diode seems to be working. I'll probably replace the fuse with a removable blade.