The AM Forum

I am having trouble locating any specs for these transformers:

1)  Triad #75176.   It looks brand new, but it does not appear in their website product search.

2)  Hill Magnetic Products #AP 10459H.   Does not produce a single Google hit.

Thanks for any info.
Steve KK7UV

Find the winding with the highest resistance and drive it with a variac.
Put 10 volts into the winding and measure the voltage across all the other windings. Install an AC amp meter in series with the variac and slowly increase the voltage. Eventually you will be able to see the ratios of each winding and determine which is the primary and which are the outputs. Once you know the primary drive it with the variac with series amp meter. The amp meter is so you can see when the transformer is going into saturation. Be careful with high voltage outputs...they can kill you. You can determine the power rating by the cross sectional area of the core.

I had done that but was hoping to compare my results to published specs.  My bench tests indicate:

1)  Triad has dual primaries and a non-c.t. secondary.
115vac produces 1530vac, and I guess 230 would produce 3060vac.
I estimate 115:1380 vdc or 230:2760 with FWBridge and choke input.
At 50 lbs, I guess 1300watts CCS or 850 mA based on 1530 vac, and 425mA based on 3060vac (?)

2)  Hill has single primary and CT secondary.
120vac produces 1680-0-1680 vac.
I estimate 115vac:1500 vdc or 230vac:3000 vdc with FWCT and choke input.
At 60 lbs, I guess 1500watts CCS or 890mA based on 1680 vac (?)

I need a 2000vdc supply for my Big Rig project.  I'm thinking I need a variac to use either one of these trannys.

If I'm not screwed up to this point of the logic train,  now I need to know how to figure out what current rating I need in a variac.

Steve, KK7UV

Steve #1 at 115 vAC, was both primaries in series so each saw 1/2 voltage to assume 230 would make higher voltage. if So I agree
 Dual primaries are in parallel at 115 and series 230. Both make the same seconadry voltage.

Actually, I ran the primaries in parallel - at several input voltages ranging from 5 to 55 vac and found a 13.3 transformation ratio - thus the 115:1530 guesstimates.  If I ran 230 on the parallel primaries, I estimated 3060vac out.  I did not try the primaries in series, but just assumed that 230 across series primaries would be the same as 115 across parallel primaries.  Since I have no specs, I do not know if the manufacturer intended for the primaries.  My hunch tells me they intended 115 across each primary - either in a 115 parallel or 230 series setup - both producing 1530 output.

You can't parallel 115 vac primary windings and run 230 volts on them. This will put it into hard saturation and cause you a trip to the breaker panel. A 115 volt winding will saturate around 130 volts.
You might consider a cap input filter to get you closer to 2000 volts.