Velodyne switching PSU ?

[bianchi77]

Dear Members,

I try to fix Velodyne PSU,
PCB code :
ESA-742 SPS-02 P/N:012-130801-001ZR,
anyone has the schematic ?

I have replaced the FET, good response few seconds, but short again,
Is it because of, I don't give a load to the supply or there's a short on the driver chip IR2153 ?
I test IR2153 with meter, there's no short so far.
IR2153 info:
https://https%3A%2F%2Fwww.infineon.c...-rbPwNN4pRILhg
page 1 and 5.

I use a 100W bulb test for checking short circuit.

Thanks

[bianchi77]

Re: Velodyne switching PSU ?

Anyone ?

[budm]

Re: Velodyne switching PSU ?

You may get more help if you upload the pictures so we can see what we are dealing with.

[bianchi77]

Re: Velodyne switching PSU ?

I've changed main FET and driver IR2153, but still got short,
I saw from the bulb, is blinking and there's a sound, tick tick...
what else is short ?

thanks

[bianchi77]

Re: Velodyne switching PSU ?

I got 78 ohm from G to S on pin HO....is the driver short again ?

[stj]

Re: Velodyne switching PSU ?

is one of the big caps slightly bulged?

[bianchi77]

Re: Velodyne switching PSU ?

is one of the big caps slightly bulged?

Which one ? the 200V one ? or 100V one , there are 4 caps

[stj]

Re: Velodyne switching PSU ?

any!

[bianchi77]

Re: Velodyne switching PSU ?

any!

hahahaha

[bianchi77]

Re: Velodyne switching PSU ?

all the capacitors are good, it's alive now, thanks guys

[Pong Tsui]

Re: Velodyne switching PSU ?

all the capacitors are good, it's alive now, thanks guys

Hi,which one cap was shorted?

[bianchi77]

Re: Velodyne switching PSU ?

Hi,which one cap was shorted?

Do you have the same problem ?
Any photos ?

thanks

[mmartell]

Re: Velodyne switching PSU ?

You mind finishing up this story by stating WHAT the problem was ?

[Pong Tsui]

Re: Velodyne switching PSU ?

Do you have the same problem ?
Any photos ?

thanks

yes i had same problem on my subwoofer,checked the Q1,Q2 FET (FDPF 12N50 )and Q3,Q4 Diode (MUR1620CTA )was short.

1,Try change the Q1,Q2 and power on it had 12V and +/-15v output,2,after if try to solder are new Q3,Q4 diode,the main fuse burt and FET shorted again,check the two 330uf/100v cap is good

[stj]

Re: Velodyne switching PSU ?

cant see the other part of the board, but i suspect the chip driving the fet is bad

[PlayerOne]

Re: Velodyne switching PSU ?

all the capacitors are good, it's alive now, thanks guys

Glad to read that you where able to figure it out and get it working again. I have the same ESA-742-SPS-02 P/N: 012-130801-001ZR temporarily removed from a Velodyne EQM-12BV plate amp for troubleshooting. The subwoofer was found to not be working due to the main 115v input fuse being blown. Capacitor C10 (330uf, 100v cap nearest the power transformer) on this board was found to have popped/vented. After replacing C10 and its C7 twin next to it (even though C7 tested good...see attached photo of caps after being replaced), I tried to power the board with no load. This resulted in the 115v main power fuse to blow again telling me I have more sleuthing to do. I then discovered the diode between pin 1 and pin 2 on one of the two FEP16DTA (this is the 3 pin device housing back-to-back diodes) is shorted. The other half is OK as is its twin component to its immediate left. Well, that’s where I’m currently at...left contemplating if C10 blew because of the diode failure or if something else caused the diode to short out. I will be checking the FETs next.

Any help you might be able to provide is greatly appreciated. I’d also be very interested in knowing what you found and fixed in your specific situation.

Thanks again, sorry for the long post and happy to provide more info if needed.

[PlayerOne]

Re: Velodyne switching PSU ?

Anyone have any guidance? Anyone have a schematic available?

[PlayerOne]

Re: Velodyne switching PSU ?

yes i had same problem on my subwoofer,checked the Q1,Q2 FET (FDPF 12N50 )and Q3,Q4 Diode (MUR1620CTA )was short.

1,Try change the Q1,Q2 and power on it had 12V and +/-15v output,2,after if try to solder are new Q3,Q4 diode,the main fuse burt and FET shorted again,check the two 330uf/100v cap is good

Is the problem now fixed? I’m still working on mine and waiting for replacement components to arrive before I can continue.

One thing I discovered is my original Q3 & Q4 FEP16DTA common anode rectifying diodes (marked on the TO-220AB case as being manufactured by Fairchild Semiconductor...Fairchild is now ON Semiconductor) is now an obsolete component. The obsolescence notification letter that was published at the time lists the replacement component as ‘none’ so finding a suitable replacement requires some careful consideration. I was able to track down MUR1620CTRG and after rereading your post, I realized you may have done the same; although you list the part number as MUR1620CTA. Was this just a typo or was the original component on your board actually an ON Semiconductor MUR1620?

In any event, I mention this because the FEP16DTA (the original part on my board) description on Digi-Key website states the max current rating is 16A FOR EACH DIODE (the actual data sheet for this part does not distinguish if the 16A rating is for each diode or if it’s for both diodes combined) - please see attached screen shot. The MUR1620CTRG data sheet lists the max current for the device as 16A, which seems to be a match, however it states that this is a combined rating and that each diode only supports 8A. Could this explain why your power supply only lasted a few moments after installing Q3 and Q4 using the MUR1620?

Another difference between the FEP16DTA and MUR1620CTRG is Peak Forward Surge Current rating; the FEP is 200A while the MUR is rated at only 100A. I have not decided yet if this is significant or not and would welcome any thoughts. My initial guess is it is not significant, but will need to investigate further.

I also found another possible replacement for FEP16DTA using NTE6244, but it has very similar specifications as the MUR1620CTRG so may have same 8A vs 16A concern described above.

Would love to know more about your situation and if it has been fixed or if you learned anything more.

[PlayerOne]

Re: Velodyne switching PSU ?

Here's a photo of the C10 capacitor before it was replaced; a pretty impressive...well...explosion. ...cap stuffing all over the place. Also attached a photo of it once it was removed. Both of the 100v caps have now been replaced so that part of the board is good to go. Still working on figuring out what else is wrong and reviving the power supply.

[PlayerOne]

Re: Velodyne switching PSU ?

yes i had same problem on my subwoofer,checked the Q1,Q2 FET (FDPF 12N50 )and Q3,Q4 Diode (MUR1620CTA )was short.

1,Try change the Q1,Q2 and power on it had 12V and +/-15v output,2,after if try to solder are new Q3,Q4 diode,the main fuse burt and FET shorted again,check the two 330uf/100v cap is good

One thing to look out for is that Q3 and Q4 rectifying diodes are not the same part number...Q3 is common cathode and Q4 is common anode. I made the mistake of thinking they were the same and blew C7 after replacing both Q3 and Q4 with the common anode configuration. Thankfully R_J (forum member) was able to spot the error. Hope you were able to get your ps running again, but wanted to pass this along just in case.

BTW, I noticed on the front page ‘Features’ part of the data sheet of my originally installed Q4 diode rectifier that it supports 8A per diode so the MUR1620 current rating is compatible (also 8A per diode, 16A combined).