1.2 ohm 1w resistor replacement

[BlkSmth]

I have a 1.2ohm 1w resistor that seems to need replacement. not sure what the rules are for them when replacing with others of not exact values. I dont have any locally, but I do have a 1.8ohm 3w ... this is next to a mosfet if that makes any difference. Thanks in advance!

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

i've got one .97ohm 1w would that suffice?

[Toasty]

Re: 1.2 ohm 1w resistor replacement

Where is this going into? What kind of circuit?

Why do you think the old one is bad? Measured resistance?

[Th3_uN1Qu3]

Re: 1.2 ohm 1w resistor replacement

If it's next to a mosfet it's likely a current sense resistor. You need that exact value. The old one is probably bad because it exploded as it often happens when the mosfet dies in this kind of circuit.

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

it belongs to this thread:

https://www.badcaps.net/forum/showthread.php?t=14701

i blew out the Q803(mosfet) by shorting pins 2,3 ... i've replaced the Q803 and removed the R811 and tested it. I get infinite on the resistor while removed on all settings of the DMM. This machine is an elo 1525l monitor. I've got a same/ similar circuit on another elo 1547 that has a bad screen in it with horizontal lines. The parts are almost the same, just diff layouts. The Q803 was a mosfet sss4n60b replaced with an stp4nk60zfp for ok upgrade per plainbill. seems that i thought the resistor was good... i think it poped the R811 and during original testing I had it in circuit. now that its out its for sure bad? not sure of replacement resistors to be exact values... sucks i just got my digikey parts last week heheh. The elo 1547l had a mosfet of stp4nkzfp i was trying, but burned it up during removal somehow... bad luck i guess! replaced it in the donar 1547l (paying peter back), screen is the same but the repair from robbing it worked. Thats what i get from shorting it, then robbing peter to pay paul

so elo 1525l had 1.2ohm 1w
elo 1547l has .97ohm 1w ...would steal it since the screen is damaged to try to repair the other monitor.

[Th3_uN1Qu3]

Re: 1.2 ohm 1w resistor replacement

The effect of using the lower value resistor in the sense circuit would be that the overcurrent protection will only kick in at a higher level. It'll work if you don't do dumb things around it.

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

It will take that as a two thumbs up for the lower value resistor .97ohm
no, no, no more dumb things.........heheh I will post them results

[Toasty]

Re: 1.2 ohm 1w resistor replacement

Grrr.

Please don't spread a discussion over multiple threads. Stay in the original post and let those guys handle it. This just wastes time and resources.

You are correct that brown-red-gold-gold is 1.2Ω - 5%, not the 0.12Ω that was originally stated.

0.12Ω - 5% would be brown-red-silver-gold

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

update #1:

the value of this resistor removed is 1.2 on the 200 setting thats a smile to me. even though its colors indicate .97ohm

gonna solder this bad dog in.

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

solder went ok. screen still the same... and no power to the top half of the board

[Th3_uN1Qu3]

Re: 1.2 ohm 1w resistor replacement

the value of this resistor removed is 1.2 on the 200 setting thats a smile to me. even though its colors indicate .97ohm

That's the resistance of your multimeter probes at play.

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

Grrr.

Please don't spread a discussion over multiple threads. Stay in the original post and let those guys handle it. This just wastes time and resources.

You are correct that brown-red-gold-gold is 1.2Ω - 5%, not the 0.12Ω that was originally stated.

0.12Ω - 5% would be brown-red-silver-gold

Where did I post that value of 0.12? I dont recall that one.

Well the topic isnt off topic... The topic was infact about a hard part. (Resistor to be specific) This post was for (before I was asked questions) was simply to find out rules about resistors when replacing with correct/not correct values/watages. If you dont know, thats ok. I still dont know either. It's perfectly clear I am a noob on that subject. Is there a better spot on this forum that I should be asking this question other than:
" Badcaps Forums > Electronics Theory and Troubleshooting > General Electronics "
If there is/was a diff location to post this unusual question Toasy, it would be much appreciated if you'd being sharing that one with me. Then I'll oblige. Thanks for your time.

[Toasty]

Re: 1.2 ohm 1w resistor replacement

Keep it in the original topic where PlainBill and Retiredcaps were responding to you.

>>Where did I post that value of 0.12? I dont recall that one.<<

PlainBill did, not you. You later discovered the value correctly.

[BlkSmth]

Re: 1.2 ohm 1w resistor replacement

Since my meter likes to play (junk one for about 70.00) what would be a good one m8's'? The value of that .97ohm measured at 1.2 and my 1.8ohm measured at 2.2 ...thats .4-.5 off

[Th3_uN1Qu3]

Re: 1.2 ohm 1w resistor replacement

Short the leads together and see what it reads. Then keep that value in mind and subtract it from any low value resistor you measure.

My best meter is currently an Uni-T UT60E. It's good, but there are a few things that would need improvement: The autorange is slow, the capacitance measurement has a high residual which needs to be removed with the relative button, and the backlight only works when the battery is brand new.