Superman2107

Member
Joined
Jan 6, 2017
My cps275 +/- 17V light is not on, is it causing stop give the power to my console? I can see the lights on and off a sec when I shut down the cps275 on my console. Checked the fuse, doesn't seems like blew. Does anyone know what is happening?
 

pcrecord

Quality recording seeker !
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Joined
Feb 21, 2013
My cps275 +/- 17V light is not on, is it causing stop give the power to my console? I can see the lights on and off a sec when I shut down the cps275 on my console. Checked the fuse, doesn't seems like blew. Does anyone know what is happening?
Does the console work ? if yes, it may just be the power light bulb. If not, well this answer your first question.
If the light bulb is ok and fuses are ok chances are the unit is defective. Could be a few capacitors or resistances..
If you have no experience in electronic diagnostic, bring it to a repare shop.
Or buy another one and keep it as back once you made this one repared :
http://www.ebay.com/itm/Soundcraft-...dio-Mixer-Console-CPS275-RW8022-/282063618136

There is some schematics in the manual : http://www.lacompagnie-events.com/pdf/cps250_275_user_guide.pdf
 

Superman2107

Member
Joined
Jan 6, 2017
Does the console work ? if yes, it may just be the power light bulb. If not, well this answer your first question.
If the light bulb is ok and fuses are ok chances are the unit is defective. Could be a few capacitors or resistances..
If you have no experience in electronic diagnostic, bring it to a repare shop.
Or buy another one and keep it as back once you made this one repared :
http://www.ebay.com/itm/Soundcraft-...dio-Mixer-Console-CPS275-RW8022-/282063618136

There is some schematics in the manual : http://www.lacompagnie-events.com/pdf/cps250_275_user_guide.pdf
The console is not working, the light bulb of the cps? No, it doesn't light up, fuse should be fine. But how does that happen? What makes the capacitors or resistances stop working suddenly?
 

Boswell

Moderator
Joined
Apr 19, 2006
This could be a fault in the console.

Which exact model of console is this powering? Do the power supply lights stay on if you apply mains to the power supply with the d.c. output connector unplugged?

The CPS275 manual says:
The +/-17V rails can withstand a short to ground or each other for up to one second;
if the short circuit remains for longer than one second then both of the 17V rails will
be shut down. To reset them the supply must be switched off for 6 seconds and then
switched on again.
 

pcrecord

Quality recording seeker !
Well-Known Member
Joined
Feb 21, 2013
fuse should be fine.
Should is not a word to use when doing diagnostic..
Many have blown the cps275 simply by pulling the plug without proper shutdown...
Boswell has a good understanding of electronics. Follow his lead ;)
 

Superman2107

Member
Joined
Jan 6, 2017
This could be a fault in the console.

Which exact model of console is this powering? Do the power supply lights stay on if you apply mains to the power supply with the d.c. output connector unplugged?

The CPS275 manual says:
Ghost 32LE, yeah PSU lights on but the +/- 17v light off
 

Boswell

Moderator
Joined
Apr 19, 2006
Are you saying the +/-17V lights are off even when the power supply is disconnected from the mixer?
 

Boswell

Moderator
Joined
Apr 19, 2006
It depends on how you view it. A linear power supply is easier to fault-find than a console, but against that you have the danger associated with working in a live mains environment.

I can guide you through a diagnostic process, but I have to ask what your electronic repair skills are like?
 

Superman2107

Member
Joined
Jan 6, 2017
I opened it and one internal from +/- 17V fuse blown, but i couldn't find the right amps tho, I checked the manual says 5.25amps, but the fuse that blown was 10amps and the working one is 10 as well. any idea which one should i put in?
 

Boswell

Moderator
Joined
Apr 19, 2006
I opened it and one internal from +/- 17V fuse blown, but i couldn't find the right amps tho, I checked the manual says 5.25amps, but the fuse that blown was 10amps and the working one is 10 as well. any idea which one should i put in?
The manual says F1 (for the +17V rail) and F2 (for the -17V rail) should both be 6.25A for the CPS250 PSU and 10A for the CPS275. You have the CPS275, so the 10A rating is correct. F3 protects the 48V rail, and should be 1A for both PSU models. Note that these fuses must all be T types, i.e. fast-acting - do not replace with a standard type.

So which fuse number (F1 or F2) is the blown one?
 

Superman2107

Member
Joined
Jan 6, 2017
The manual says F1 (for the +17V rail) and F2 (for the -17V rail) should both be 6.25A for the CPS250 PSU and 10A for the CPS275. You have the CPS275, so the 10A rating is correct. F3 protects the 48V rail, and should be 1A for both PSU models. Note that these fuses must all be T types, i.e. fast-acting - do not replace with a standard type.

So which fuse number (F1 or F2) is the blown one?
 

Superman2107

Member
Joined
Jan 6, 2017
Tried with the new fuse, it blow right away, probably the bridge recitifer? Is it the 10A 200V, mounted on the heat sink? Thanks!
 
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