I have about 13 HPS and 7 MH ballasts, or rather I thought I had bought 13 HPS and 7 MH ballasts. In reality I bought 10 dual 400W bulb pool uplight fixtures with one MH and one HPS bulb each. Some of the MH ballasts had been replaced with HPS ballasts, but still had the MH bulb... Long story short the were left outside facing up and there are no drain holes, so they were literally submerged in water for a couple months. That being said I do not trust the windings. I didn't lose much, since the capacitors alone were worth the money I paid for the lot. So essentially I have 20 400w ballast cores, and would like to use them to make filament transformers and the like. Do ballast cores have any special properties like shunts in an MOT? Or are they just bog-standard magnetic cores ready to serve whatever purpose I see fit?

 

Most have a set of shunts between the primary and secondary windings that are easily knocked out.

As for the the present windings, a typical commercial grade HID ballast is wound with class high temperature H or H+ windings and built to work in very harsh environments so they have no real issues with getting wet or being placed in and oven and baked at 230- 250F for several hours to dry them out as well.

If the cores didn't get corroded a good clean soapy water scrub and rinse followed a good hour or two bake at ~230 - 250F might bring them back to life so I wouldn't write them off yet as being junk just because they were wet for a while.

 

I may just try baking them then, and see if they test ok. Hopefully it doesn't smell too bad, the stagnant water they were sitting in wasn't exactly clean... Thanks!