ps50b451b2wxxu clicking not turning on

[Blueeyes]

Re: ps50b451b2wxxu clicking not turning on

Pin
2=.16
3=1.6
4=nothing
5=1.6
6=nothing
Resistors are fine I am a little worried when I flipped board over I found this
Seems its been soldered badly and few burns any chance its related?
No shorts found

[flocko]

Re: ps50b451b2wxxu clicking not turning on

Pin 1+2 are the Vs this is short (.16 ohm ?) But please check again, By the looks this board has been worked on before in the photo that's just were it has been soldered, the parts to check are Q804/5/8/9/ Q810/11 and there gate resistors and ICs U800/812 these are the parts that would be shorted or blown and I would recommend replacing . I have now looked and I have a board should you need it.

[Blueeyes]

Re: ps50b451b2wxxu clicking not turning on

II'll send picture of my dmm its a cheap one as haven't got round to buying decent one but show 1+2 open and low ohms yeah I'd say it has looks like one or two places board is actually missing solder point on q808 q811 so would I check these the same way as normal resistors? I'll upload picture of missing solder joints and how much would you want for the board?

[flocko]

Re: ps50b451b2wxxu clicking not turning on

That would have to be one of the worst jobs I have seen and believe me I have seen some, well the problem you have is that these are some of the parts I have listed so it looks to have badly repaired in the past, my money would be on having to replace all on my list as you have a short on the Vs and bad soldering will not be the problem ,but would be the cause of the blown parts , can you give some background on the set did you buy it faulty or has it been running .

[Blueeyes]

Re: ps50b451b2wxxu clicking not turning on

Yeah I picked it up with a with the clicking fault but my first attempt at susing out the problem failed as I thought it was dead capacitors apparently not but looks like its a very bad repair so thinking I'll just get all parts and redo the whole thing , I saw it as a little project I have a few broken set I'm trying to fix

[Blueeyes]

Re: ps50b451b2wxxu clicking not turning on

This is DMM and setting I'm using to test for shorts and the resistors

[flocko]

Re: ps50b451b2wxxu clicking not turning on

Off hand the parts Kit for this board runs at about £30.00. and can be had from OHM supplies just make sure to get the right kit for your board (rev AA1) as the AA3/AA6 do not use the same parts , it makes it easier to get all the parts from one place , but you can get them any were just use part numbers. But make sure to check SMD gate resistors and change ICs or could blow all your nice new parts and be back to were you started, have fun if you run into a problem just ask ,as I say I have boards here if you want send a P.M

[Blueeyes]

Re: ps50b451b2wxxu clicking not turning on

Thanks I'm thinking desoldering the ic might be a little beyond me with my maplin soldering iron

[Max075]

Re: ps50b451b2wxxu clicking not turning on

flocko, I have the same problem. clicking. but soldering is fine.
Flocko please can you send the part numbers and location no in that OHM supplies repair kit?
Also it says check R5085 / R5086 before buy, but i can't find them on the board?
please reply

[flocko]

Re: ps50b451b2wxxu clicking not turning on

Hi Just seen this, so i hope i can help firstly what is the part number on your board ? will need the LJ92-XXXX found on the bottom off your board you will also find there the rev number AAx in the white box, these boards had a few over time with changes to components, so to get the right parts list this is a must have number Flocko

[Max075]

Re: ps50b451b2wxxu clicking not turning on

Hi Flocko, the numbers are;

PBA NO: LJ92-01601A
REV: AA1

PCB NO: LJ41-05905A

I found out Q811, Q808, Q810, Q809, Q805, Q804 are shorted and I removed them.
Also the diods D820, D802, D819 seems to be shorted but the diods are fine. I checked one of them after removed from the board.

I also checked the buffer ICs (IC G with output pins) and they are not shorted

[Max075]

Re: ps50b451b2wxxu clicking not turning on

Hi Flocko, the numbers are;

PBA NO: LJ92-01601A
REV: AA1

PCB NO: LJ41-05905A

I found out Q811, Q808, Q810, Q809, Q805, Q804 are shorted and I removed them.
Also the diods D820, D802, D819 seems to be shorted but the diods are fine. I checked one of them after removed from the board.

I also checked the buffer ICs (IC G with output pins) and they are not shorted

found out that dioad short due to R818. Is that normal?
Checked following resistors after removed Q811, Q808, Q810, Q809, Q805, Q804

R912, R900, R909, R836, R833 = 7 ohm
R901 = 116 ohm

Also checked U812 and U800 and they are not shorted.

[flocko]

Re: ps50b451b2wxxu clicking not turning on

Have you checked across R904 +R905 For low ohms? if it does show low ohms you have one or two buffer ICs faulty. has your board got the 100k resistor fitted to the back of the board to D823 +Q809 I would go with a kit and change all the parts, but make sure to get the right kit for your rev number, to not change the driver ICs is a mistake and can be a costly one, when the IGBTs go short they can take the drivers with them and in some cases the gate resistors as well. not all ways but if not gone they will be weak and not long for this world. Flocko
diodes D802/820/819 will show 2.7ohm short this is normal. Andy does a kit with all 16 parts £21.00 trade +vat and post ohm supplies

[Max075]

Re: ps50b451b2wxxu clicking not turning on

R904 +R905 = 23 K
and yes it has the 100k back of the noard

If you think need to replace all the parts can you send me the part numbers pls
Max

[Max075]

Re: ps50b451b2wxxu clicking not turning on

Have you checked across R904 +R905 For low ohms? if it does show low ohms you have one or two buffer ICs faulty. has your board got the 100k resistor fitted to the back of the board to D823 +Q809 I would go with a kit and change all the parts, but make sure to get the right kit for your rev number, to not change the driver ICs is a mistake and can be a costly one, when the IGBTs go short they can take the drivers with them and in some cases the gate resistors as well. not all ways but if not gone they will be weak and not long for this world. Flocko
diodes D802/820/819 will show 2.7ohm short this is normal. Andy does a kit with all 16 parts £21.00 trade +vat and post ohm supplies

Flocko is it £29+vat kit?
http://www.ohmsupplies.co.uk/epages/...roducts/KIT238

or do you have a service manual or or part list pdf for this then i can find out if it is cheaper to buy separate as i do not have a trade account.

Also i'm not sure about R901 as it looks burned. small spot on it. gives 116 ohm
so its really appreciate if can let me know their values.
R901
R5091
R5082
R5089
R5083
R5025
R5024

[flocko]

Re: ps50b451b2wxxu clicking not turning on

I do not think it will be cheaper to buy in separate parts even with no trade account
parts for Rev AA1 LJ92-01601A
Q809/810 RJH3044
Q808/811 IRFP4332
Q804/815 FGPF50N33
R900/901/909/912/833 6R2 6.2ohm
U800/U813 IRS21956S
U812 ADUM1410 this IC if not changed can over volt the buffer ICs and total the board

good luck it looks a lot of parts, but if you leave any unchanged you can and will blow them again on power up so dont try shortcuts Flocko

[Max075]

Re: ps50b451b2wxxu clicking not turning on

I do not think it will be cheaper to buy in separate parts even with no trade account
parts for Rev AA1 LJ92-01601A
Q809/810 RJH3044
Q808/811 IRFP4332
Q804/815 FGPF50N33
R900/901/909/912/833 6R2 6.2ohm
U800/U813 IRS21956S
U812 ADUM1410 this IC if not changed can over volt the buffer ICs and total the board

good luck it looks a lot of parts, but if you leave any unchanged you can and will blow them again on power up so dont try shortcuts Flocko

Thanks Flocko. yeah i'll check if not i'll buy the kit.
let you know when its done. cheers

[flocko]

Re: ps50b451b2wxxu clicking not turning on

I had a look on ebay the kits on there dont cover all the parts,and as for separate parts, I gave up when the list started going over £35.00 and I was still a long way from the end. but with board prices at over £80 still a cheap repair. Flocko

[Max075]

Re: ps50b451b2wxxu clicking not turning on

Thanks for the info. Just tried to buy kit from OHM suppliers. Its £42 with the tax. So decided to buy parts.

Is it ''6.2 Ohm 6R2 1W 5%'' for the resistors?
one more thing, is there a better place to buy RJH3044? Utsource will take 3weeks

Max

[flocko]

Re: ps50b451b2wxxu clicking not turning on

the cheap option is to buy from China and they will take a time to get to you, ebay is an option but will be the high cost one, I think a lot more then Ohm Supplies, but that is your call. The resistors I keep are SMD 1206 1/4w 5% and I use these on this type of job and power boards. I have also given you the wrong part number for U813 it is a IRS21856S this being 14pin the IRS21956S 20pin for U800 Flocko