Behringer UB2442 New psu schematic

[blindboybenton]

Good afternoon / morning

I have a Behringer UB2442 with a blown up psu. I got a downloaded schematic, but this one has the Switch mode psu schematic missing
Does anyone have a schematic for this model or something from the same range

Have a nice day

BBB

[doctor]

Good afternoon / morning

I have a Behringer UB2442 with a blown up psu. I got a downloaded schematic, but this one has the Switch mode psu schematic missing
Does anyone have a schematic for this model or something from the same range

Have a nice day

BBB

Try this.

[blindboybenton]

Many thanks Doctor.. Its spot on

BBB

[blindboybenton]

Hi doctor

Have you ever had a luck repairing these psu's.... Im pulling my hair out here. When i got the mixer customer said it was going off and on. Found it too be dead. Checked a few thing and decided to change the TOP245 and Opto coup, Still dead. I then got the schematic. Ive changed the 2 low value caps and checked all semi conductors.
PSU not starting up .. not even trying. There is nothing on Pin 1 of TOP245. Pin 2 has 4v. Pin 7 about 300v. No shorts on secondary. Ive agreed a price with customer and now, im thinking of calling it a day, too much time for a little about of money

What was your faults with your psus?

many thanks in advance

BBB

[diydidi]

Check values of R10,11,12 and check D7. Report back.

[blindboybenton]

Thanks

Have just rechecked R10-11-12 all ok at 680k and D7 reading correct with one leg lifted

[diydidi]

Just checking my notes. I once measured 2,6V on Pin2 on a working power supply. Could it be, you still have a faulty Top245?
What is your measured voltage accross C7? Should be in the region of 310 -320V.

[blindboybenton]

I will buy another one i could only get top247 which is a higher spec version, this one is getting warm. for me its time this one is fixed for returned. too busy to have too much time caught up in it


Thanks i will let you know

BBB

[Enzo]

I surely hope you were using an isolation transformer to work on this SMPS.

Did you try the power supply with the loads all disconnected? Did it try to start that way?

One very common reason for an SMPS to refuse to start is excessive load. That can be from a shorted load, but also can be simply a shorted rectifier on the secondary side. D4,5,6,8,9.

[blindboybenton]

Hi Enzo... Im sorry to say i don't have a isolation tx something on my list of things too get. I will be taking the last look this afternoon.
Im too busy to get held up on things like this, but i hate it costing me money and i don't want too return equipment U?R

Ive checked all the diodes on the psu. I think its a primary fault. Customer didnt want to pay what he is paying , let alone any more. Had one of the same mixers in 1 week earlier, wish it was still here

BBB

[Jazz P Bass]

Something is amiss.

That TOP245 is a self running ic.

[blindboybenton]

Hi Jazz bass. Yes i'm aware of the TOP245. Ive checked about everything and still dead. Im going to order another TOP245 from another supplier. and see what happens
Its taking up too much of my time and i can't afford that



BBB