ADA8000 Behringer No Power
- Thread starter ReRibbon
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joakimkarlthomas
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I have one that I bought faulty. It powered on but had no sound going through. There is 4 bigger electrolytic caps inside and 3 of them was bad in mine. The 3 that sits near a few regulators. I swapped them and now the unit works. Might be good to check these caps.
Just to be crystal clear here ,
you removed the plug from the mains I assume , then measured across the live an neutral legs of the IEC input socket on the equipment for continuity within the unit itself ? It half seems from what you said above you checked the live mains outlet at the wall for continuity , in which case you probably would have blown the crap out of your multimeter . If theres even a slight chance you dont know what your doing , DONT TOUCH LIVE MAINS POWER WITH YOUR MULTIMETER .
Lets assume you and your multimeter are still alive , and you have established continuity across the transformer primary , Now clean off the hot glue and disconnect the white plug with the grey orange and yellow wires to the circuit board from the transformer secondary , check each pair in turn for continuity , also check for shorts between yellow grey and orange windings . your still completely disconnected from mains power at this stage .
Assuming all the above checks are good , now apply power to the unit and check each secondary pair( Grey orange and yellow)on the transformer on the AC volts range on the multimeter , bear in mind you may still be dealing with dangerous voltages ,so dont touch anything with your bare hands and dont allow the probes to short together while measuring.
You should read a different AC voltage on each of the three windings , one for the 5 volt rail , one for the 48 volt supply and one for the +/- 15 volts supply . If thats all present and correct you know your transformer is working , the problem is further on in the circuit .
you removed the plug from the mains I assume , then measured across the live an neutral legs of the IEC input socket on the equipment for continuity within the unit itself ? It half seems from what you said above you checked the live mains outlet at the wall for continuity , in which case you probably would have blown the crap out of your multimeter . If theres even a slight chance you dont know what your doing , DONT TOUCH LIVE MAINS POWER WITH YOUR MULTIMETER .
Lets assume you and your multimeter are still alive , and you have established continuity across the transformer primary , Now clean off the hot glue and disconnect the white plug with the grey orange and yellow wires to the circuit board from the transformer secondary , check each pair in turn for continuity , also check for shorts between yellow grey and orange windings . your still completely disconnected from mains power at this stage .
Assuming all the above checks are good , now apply power to the unit and check each secondary pair( Grey orange and yellow)on the transformer on the AC volts range on the multimeter , bear in mind you may still be dealing with dangerous voltages ,so dont touch anything with your bare hands and dont allow the probes to short together while measuring.
You should read a different AC voltage on each of the three windings , one for the 5 volt rail , one for the 48 volt supply and one for the +/- 15 volts supply . If thats all present and correct you know your transformer is working , the problem is further on in the circuit .
That seems like a really important thread to read for any ADA8000 owners. It explains why I have seen multiple complaints from ADA8000 owners that the units run really hot.
I did not see in that thread information on how much current is consumed by each rail, so can't check whether the power dissipation in the regulators is within spec for long term use. It seems at least larger heatsinks on the regulators and a chassis fan would be warranted if the transformer is not going to be replaced.
Does yours beep with continuation? No, correct?
Seems more like a bad multimeter...
48,5 Ohms isn't continuity. If that was a switch, it would be defective.
I completely desoldered the primary from the IEC jack. One is red, one is blue. I put my meter leads to them and it comes to 48.1 ohm. If I set the beep function on for continuity it reads 48.1 and also beeps indicating the +and - leads are somehow grounding each other out.
That would indicate a bad primary, No?
The IEC connector depending on the position of the fuse holder sets either 110 or 230 volt opperation .
Its as simple as this , the primary section dedicated to 110v measures 20 ohms ,the entire primary dedicated to 230v measures 70 ohms . There wasnt any need to desolder anything . I measured across the terminals of the IEC socket at the back of the unit , I didnt even have to take the lid off . Wire everything back up the way it was , repeat the test at the external live and neutral terminals of the IEC , flip the fuse holder (check fuse for continuity while your there) , find 20 ohms for 110v and 70 ohms for 230 and dont forget to return the fuse to its proper setting again after .
Its as simple as this , the primary section dedicated to 110v measures 20 ohms ,the entire primary dedicated to 230v measures 70 ohms . There wasnt any need to desolder anything . I measured across the terminals of the IEC socket at the back of the unit , I didnt even have to take the lid off . Wire everything back up the way it was , repeat the test at the external live and neutral terminals of the IEC , flip the fuse holder (check fuse for continuity while your there) , find 20 ohms for 110v and 70 ohms for 230 and dont forget to return the fuse to its proper setting again after .
You misunderstood the earlier posts. No one ever suggested disconnecting the transformer from the IEC connector, the suggestion was to measure directly from the IEC connector pins through the transformer (see posts #17 and #24, from Tubetec). And the previous description of a transformer failure was that it failed open, i.e. no continuity or open circuit (a multi-meter would usually show something indicating over-range, out of range, etc.). Your reading of around 50 Ohms would indicate that the transformer primary has not failed.
Now you have to re-attach the transformer leads to the IEC jack (make sure not to mix up which lead goes where since the jack has the 120V/230V switch on it), and check the voltages at the output. Based on the earlier pictures the regulators with brown discoloration around the heat sinks have likely failed. See post #17 from cyrano, "The voltage regulator(s) look fried..."
How do I look for that?
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