Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

[lotas]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

Why do you need these tables, buy them or find them on donors with the same markings (SCK 102) and change your burned ones

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

reason is im trying to find ones which i can use instead of ordering the same ones from china which will take a month to arrive.
the shop near me is RS components, which i can get to easily and they have a lot of stuff in stock.

also i believe the website here: https://www.lcsc.com/product-detail/...Y_C211173.html
seems to have different info on the product page compared to the datasheet. webpage says its 3A but datasheet says its 2A so thats where i was getting some confusion from.

there is this one here: https://uk.rs-online.com/web/p/thermistor-ics/1857867
that seems to be close on specs rated at 2A has 30second Thermal cooling time constant but only 1.4w power rating which is less than the original ones 2.3w. capacitance at 240v is also a lot less at 100uf vs the originals 220uf.

im in the United Kingdom so if anyone know what i can get a hold of quickly it would be much appreciated.

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

iv marked the back of the board here, red box is the thermistors and blue boxes are the legs of the relay. dunno if it helps trace something but the more info the better i guess

[lotas]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

They (thermistors) are connected in series to the closing contacts of the relay, for a soft start.

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

They (thermistors) are connected in series to the closing contacts of the relay, for a soft start.

thanks for that info. do i have to use the exact original thermistors that were there or can i use any which are marked as 10ohm 2 amp?

[vinceroger69]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

They (thermistors) are connected in series to the closing contacts of the relay, for a soft start.

Lotas could this be causing his remote control issues too? or will it be a diffrent fault

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

Lotas could this be causing his remote control issues too? or will it be a diffrent fault

i had the batteries out of the remote and this same issue happens, once tv is on it wont power off. im wondering if those thermistors are blown are they responsible for power off the tv and keeping it off?

[lotas]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

Replace them, you can put one at 20 Ohm.

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

Replace them, you can put one at 20 Ohm.

can i use these ones linked in the pic below or will they blow up?
also i noticed the data sheet says they have a cycle life of 1000 could this by why the original ones popped after 5 years of use with tv being used multiple times every day?

also i forgot to add i got a multimeter across the blown thermistors and the have values of 38.5ohms and 226kohms. the working one has 14.2ohms (around 16c temp in my room) and when i hold it with my fingers its ohms start dropping down.

[lotas]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

38.5ohms and 226kohms - These are no longer workers, especially the second one.

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

38.5ohms and 226kohms - These are no longer workers, especially the second one.

Thanks for the reply, did you have a look at the specs of the tdk ones i posted above? Would they be safe to use?

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

hey all, i replaced the 2 thermistors and now its working properly. tv turns off and stays off.
question is now, the 3rd thermistor on the board that is not blown up should i replace it too or leave it as it is?
had to buy a 5 pack of thermistors total cost was £2.90ish so iv got 3 left.
got to thank everyone for their support.

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

Changes the third one too. Tv is back on the wall and woring great

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

TV still doing great. was wondering how long are these thermistors supposed to last when used as inrush current limiters? i thought they should go 10-15 years atleast?

[slybunda]

Re: Bush (Vestel) led40127fhdcntd - turns off and on repeatedly

just an update, tv is still going great. still dont get why the thermistors popped. i do feel like getting a working tv with smashed screen and using its powerboard for full recap and upgrade of other components and to keep as spare? what way can switch over with no downtime.