Crown Xti 1000 - No power

[chgrove]

Amraks Have you ever figured out the issue? I believe I have the same problem. Voltage drop like you described. That little tiny tick (which isn’t coming from the relays k1 and k2 and I could swear it’s around the T1 transformer). The voltage goes all the way up to 300v on the v_bulk and v_bulkrtn and then drop back again. Each time that little tick happens, the voltage on C196 which almost gets to 24v drops back to 10, then 16, then 20 and tick, goes to 10.

I haven’t checked Q28 and 31. They are just hard to get to since they are attached to that heatsink so I didn’t want to take them out yet. I verified the relays (by taking them out and testing them), same with C196, same with all R370-373. I don’t get that 15v though and this post has finally made me understood it’s not the 30v I’m after but the 15v. I’ll check the R348 and R350 and then I’ll check all of Q26 to Q31 by removing them and testing them out of the board since I don’t know how else.

However, if you remember which of those pieces were the issue, I’ll remove that one first!

Sorry for reviving your old post. I’ve just been at this for more than 30 hours now and I was just about to give up and buy another one before finding your post.

Hi, I have the same problem with a DSI 2000. have you solved the problem? my voltages also oscillate.

[jondion]

Amraks Have you ever figured out the issue? I believe I have the same problem. Voltage drop like you described. That little tiny tick (which isn’t coming from the relays k1 and k2 and I could swear it’s around the T1 transformer). The voltage goes all the way up to 300v on the v_bulk and v_bulkrtn and then drop back again. Each time that little tick happens, the voltage on C196 which almost gets to 24v drops back to 10, then 16, then 20 and tick, goes to 10.

I haven’t checked Q28 and 31. They are just hard to get to since they are attached to that heatsink so I didn’t want to take them out yet. I verified the relays (by taking them out and testing them), same with C196, same with all R370-373. I don’t get that 15v though and this post has finally made me understood it’s not the 30v I’m after but the 15v. I’ll check the R348 and R350 and then I’ll check all of Q26 to Q31 by removing them and testing them out of the board since I don’t know how else.

However, if you remember which of those pieces were the issue, I’ll remove that one first!

Sorry for reviving your old post. I’ve just been at this for more than 30 hours now and I was just about to give up and buy another one before finding your post.

[MigueMike]

Re: Crown Xti 1000 - No power

Hi. I have the same problem with a DSi 1000 that is basically the same board as XTi. In my case the amplifier turn on, K1 switch and then i can hear K2 and after few seconds the amplifier turn off. I allready replace TL494 and C196 cap. IGBTs readings looks ok.

I hope you can help me with this.
Thanks guys.
Mike.

[r3production]

Re: Crown Xti 1000 - No power

hi can you help me on the way. i have a xti2000 that comes on all the way and shows ready, after 20 sec it shuts down. i read 337 volts over tp 30 an 21 or on D24 pos neg. i see it should be 300v. what causes this. next i have a 1000xti that has 172 volt on tp30 or d24 , this amp does not come on at all, i measure 32 volts on tp31 but 2 volts on tp28 and 29. i also measured at c196 and i get 32v over that cap. hope some one can help

[Amraks]

Re: Crown Xti 1000 - No power

Not much cheaper mouser in Australia is slow, RS is usually next day.
Hoping to to use to-247 package until I am sure I have this working.

https://au.rs-online.com/web/p/igbts/1241334/ not sure if this would substitute it

[petehall347]

Re: Crown Xti 1000 - No power

mouser has them lots cheaper .no idea about shipping cost https://www.mouser.co.uk/ProductDeta...f%252BTg%3D%3D

[Amraks]

Re: Crown Xti 1000 - No power

Hey its been awhile since I have gotten around to doing this.

I made the mistake of leaving two resistors pulled up r376 and r425
I ended up blowing Q31.

Q28 is fine by the looks of it.

Is it fine just to replace Q31 these transistors are expensive not sure what I should be checking now.
not sure if I can use a different package for testing purposes.

the package it is now seems rare which is Max247
https://au.rs-online.com/web/p/igbts/6868357/

Just wondering I can substitute this for any same rated IGBT what characteristics am I looking for when comparing.

[Amraks]

Re: Crown Xti 1000 - No power

Ill keep you posted R_J thanks for your help. that schematic wasn't easy to follow being unsearchable but I think I under stand it a bit more now.

[R_J]

Re: Crown Xti 1000 - No power

Thats good, I hope thats all that is wrong.

[Amraks]

Re: Crown Xti 1000 - No power

I already have them in my shopping cart with rs.online its free shipping and next day delivery

[R_J]

Re: Crown Xti 1000 - No power

If Q28/31 are shorted, check the gate resistors also (10Ω) if they are ok and the gate drive transistors check ok, I would try replacing q28/31.
I see digikey.au carriers them https://www.digikey.com.au/products/en?keywords=stgy40

[Amraks]

Re: Crown Xti 1000 - No power

confirmed Q28 and Q31 test bad out of circuit.

I tested them NPN and PNP transistors

Q26 KSC3265 NPN

Q27 KSA1298 PNP

Q29 KSC3265 NPN

Q30 KSA1298 PNP

On multimeter
I have tested V_BULKRTN to Q27 getting O.L
I have tested TP30 to Q27 getting O.L
Positive to T30 - Negative to V_BULKRTN getting O.L
Negative to T30 - Positive to V_BULKRTN getting 0.922v

So all along it was the IGBT's

Would it be safe to replace them guys?

[Amraks]

Re: Crown Xti 1000 - No power

Ok so across Q28 and Q31 collector and emitter both ways is reading 0.00v in diode mode.
I would say these are bad?

Also this board doesn't have these like in the schematic
r682
r683
c290

c299
r794
r795

[Amraks]

Re: Crown Xti 1000 - No power

which output transistors not sure where I am looking.

[R_J]

Re: Crown Xti 1000 - No power

there is no voltage at that coil

Thats because there is only 3 volts on the secondary and not 30v. Start checking for shorted output transistors

[R_J]

Re: Crown Xti 1000 - No power

Check the voltage on D31, it should be 16 volts, this will allow the regulators to supply +15V_CTRL If this voltage is good (15 volts)

Check that there are not any shorted output transistors killing the +V1 or the -V1
This is the situation where is it the primary not providing the drive or is there something on the secondary that is shorted not allowing the power supply to operate (being in protection)
Off T1 pin 17 is LV1, (over to the right of that page) is the small circuit that drives RAIL. This RAIL signal is what the micro monitors and if the secondary voltage is where it should be, Thats when it tells the soft start relay K1 to close.

[Amraks]

Re: Crown Xti 1000 - No power

You would be better off checking the voltage on C45 to see if you are getting +30 volts.
The voltage on D26 will be misleading because it is also supplied by VK_START.
maybe? the way to find out is to measure the voltage on the coil.

there is no voltage at that coil

[Amraks]

Re: Crown Xti 1000 - No power

I found it its rising to 3v then drops back.

[R_J]

Re: Crown Xti 1000 - No power

Page 6, Off T1 pin17 through D13 to C45 (+30 volt secondary supply)

[Amraks]

Re: Crown Xti 1000 - No power

where is c45 in the schematic