You probably have the auxiliary winding hooked up backwards. You might be bucking the larger winding instead of adding to the shorter one. You want to end up with two windings of the higher number of turns, not two of the fewer. Either way will result in balance, but one way will draw more magnetizing current.
Powering up in series connected secondaries to mains voltage is not correct method ,voltage 1,5 times higher, so core saturates and draws much more current ,so bulb tester lights up.
WRONG - DANGEROUS - You may BURN your transformer with the 50% Voltage/magnetic overload.
Doubly so in a transformer where we are testing for suspect design/winding/core material.
Expect a saturated fuse blowing transformer instead.
A mess of a "measurement".
Why doesn´t that surprise me? 🙄
PLEASE TEST AS SUGGESTED AND POST RESULTS.
Edit: what ximikas said 🙂
I wonder.....
When having the two primaries in parallel, I would have thought, the first thing to do was to switch the phase of one primary and try again 🙂
I mean.... Normally you would connect BLU with VIO & BRN with GRY, but knowing that the transformer is made in China 🙂, they maybe could have made an error and switched one of the colors by mistake?? (Wouldn´t be the first time) 🙂 🙂
When having the two primaries in parallel, I would have thought, the first thing to do was to switch the phase of one primary and try again 🙂
I mean.... Normally you would connect BLU with VIO & BRN with GRY, but knowing that the transformer is made in China 🙂, they maybe could have made an error and switched one of the colors by mistake?? (Wouldn´t be the first time) 🙂 🙂
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If one of primaries would be out of phase ,it will blow mains fuses instantly , don't forget its 1000va toroid...
I always have bulb in series when connecting power supplies (The Adcom GFA-565 notwithstanding... ) 🙂
I did what I was asked... never tried this before, but it made sense. A 65w bulb in series with a 1000va Toroid is unlikely to burn it out in time limited tests... I do appreciate your concern though.
You were asked to apply 120V to the 120V primary which gave the lesser secondary voltages, and measure the other 120V primary.
No secondaries were mentioned.
Please post results.
PS: "apply 120V to primary" means literally that, no series bulbs,etc.
Just a fuse, of course, because it´s "transparent".
No secondaries were mentioned.
Please post results.
PS: "apply 120V to primary" means literally that, no series bulbs,etc.
Just a fuse, of course, because it´s "transparent".
118.5vac applied to P1 gives 118.4v on P2
3A fast blow was obliterated on first try. I then tried a more standard 15A and it is ok.
Theres a bit of buzz with just P1 driven .... is this because of the windings I put are not sealed?
3A fast blow was obliterated on first try. I then tried a more standard 15A and it is ok.
Theres a bit of buzz with just P1 driven .... is this because of the windings I put are not sealed?
I think it should be ok now to test both primaries in parallel with bulb tester . Do you have ac ammeter ? If not ,you can use resistor like 1 ohm 2w in series with mains and post results . Bulb tester first , if not light up, then just fuse , then current or voltage drop on resistor result.
11:50AM Toroid 21.7c externally. Ambient is 21.4c
Saw no bulb lighting, then connected direct but with 1 ohm in series. Voltage across 1ohm is 0.059 vac or 58.6 mV. I hear no buzzing either with both P1 and P2 in Parallel.
Seems like great news!
Will monitor temps for next 2 hours.
Saw no bulb lighting, then connected direct but with 1 ohm in series. Voltage across 1ohm is 0.059 vac or 58.6 mV. I hear no buzzing either with both P1 and P2 in Parallel.
Seems like great news!
Will monitor temps for next 2 hours.
Looks like toroid now draws 7W when no load .For 1000W toroid i think thats good .These 7W will heat up it a little ,but after longer time .Additional winding now made with correct wire ?
Probably overkill wire but yes, 14 ga. If I had 18 ga, that might have been fine too. 14 ga will work up to rated 15 amps. The primaries should not draw more than 8.33 amps at full rated power, so we are good 🙂
ximikas: Thank you so much for your help and patience. This saved me a 1kva Toroid! Mucho Gracias!
ximikas: Thank you so much for your help and patience. This saved me a 1kva Toroid! Mucho Gracias!
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