helion
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Hello All,
I have an old computer UPS which I took to the repairman. He said a transformer is not functioning and it is better to buy a new UPS instead of replacing the transformer.
I identified the transformer, and on checking the leads, I found that the continuity test for Primary coil gives reading of some resistance on the DMM while the secondary coil bleeps like it must.
I decided to rewind it by myself and I bought some thicker gauge wire(of SWG 40, the actual one was measured as SWG 43). After rewinding 2500 turns(by hand of course), even this one showed some resistance. Is this the common behaviour, or is there some small twist or fold in the new wire that can cause this to happen?
Another question: In the said transformer, there are about 4200 turns in primary coil, and about 245 turns in the secondary. Is it okay to reduce the number of turns while taking care to maintain the ratio?
Also, what is the insulating lacquer used in between the E-I laminates? What chemical compound is used for it, so that I can go and buy that too, if necessary? Is it seriously essential if I have to put back the old parts back in place, or should I buy it new and apply?
Thanks.
I have an old computer UPS which I took to the repairman. He said a transformer is not functioning and it is better to buy a new UPS instead of replacing the transformer.
I identified the transformer, and on checking the leads, I found that the continuity test for Primary coil gives reading of some resistance on the DMM while the secondary coil bleeps like it must.
I decided to rewind it by myself and I bought some thicker gauge wire(of SWG 40, the actual one was measured as SWG 43). After rewinding 2500 turns(by hand of course), even this one showed some resistance. Is this the common behaviour, or is there some small twist or fold in the new wire that can cause this to happen?
Another question: In the said transformer, there are about 4200 turns in primary coil, and about 245 turns in the secondary. Is it okay to reduce the number of turns while taking care to maintain the ratio?
Also, what is the insulating lacquer used in between the E-I laminates? What chemical compound is used for it, so that I can go and buy that too, if necessary? Is it seriously essential if I have to put back the old parts back in place, or should I buy it new and apply?
Thanks.