Mystery Part

Check TDK catalog?

RL

I think you are in the UK? Farnell and RS have those parts too.

piglet

PTCs tend to live short and difficult lives on account of thermal shock.

Cheers

Phil Hobbs

Could well be what killed this one - by making its ends detach. I'm a little worried that if this fixes the controller it won't fix the tractor - maybe some other fault is repetitively over-volting the input that this device protects.

We won't know until we try it.

And then the owner will complain about the horrendous bill.

MK

Yes, I've ordered some Murata parts from Farnell - it was the only close physical match in 180 ohms.

MK

Amazing - I'd already looked under microscope and not seen anything. With careful lighting and a digital camera microscope I could read what the phot doesn't show:

its a PTC C890 !

Thanks for your help.

MK

Ok that helps. C890 maps onto (confusingly) three Epcos types:

B598** series, leaded disk, coated 230V

--------------------------------------- C890 30 60 0.2 5 120 150 84 X X B59890C0120A070 C890 15 40 0.2 3 80 150 78.7 X X B59890C0080A070

B598*0 series, leaded disk, coated 110V

--------------------------------------- C890 35 70 0.2 6 150 78.7 X X B59890C0160A070

piglet

These types are 150 Ohm PTCs for different voltages. Unfortunately, they don't look like the one from Michael's photos:

HTH

Reinhard

I copied this from the Epcos data sheet for series B598**, January 2009,

C890 80 4.0 7.5 0.5 C890 120 4.0 7.5 0.5

C890 30 60 0.2 5 120 150 84 B59890C0120A070

It means that the parts are 4mm diameter and the drawing makes then 5mm max long - seems about right.

I've ordered some so I'll soon know.

Thanks for your help.

MK

He should try owning a new one that they won't let you repair yourself.

Cheers

Phil Hobbs

I watched an episode of millennial farmer the other day where he's using a new loaner DJ tractor and planter. He planted 100 ac and never touched the steering wheel or raised or lowered the planter at the end of the row. Everything was automatic all while the planter was placing about 300 seeds per second with 99.99% accuracy. Of course that new setup would probably be well north of $400K.

Tractor fixed !

in that context.

MK

There is a right to repair group who is making some headway in the fight ag ainst such onerous policies. Not only does the farmer have to pay high pri ces for "approved" repairs, the farmer is often down for days waiting for t he repair to happen, in particular at the busy time of season. repair.org

They also fight for repair rights in other areas such as using copyright to restrict repairs (common with the farm machinery companies). I sent them some money a while back.

BTW, it wouldn't hurt to trim once in a while.

l=0

NTC

yTa?dl=0

ard to

ck.

bad

Good Job!

Good job, shame about the price. These manufacturers have you by the 'nads with their extortionate spare part prices and it's becoming more and more difficult to do the sort of maintenance jobs our fathers and grandfathers routinely undertook without a second thought.

There is a group working on this:

The Repair Association .

Joe Gwinn