its cause they build them, then fill them full of epoxy so you cant repair or see the internal components-
they suck..period-
never waste your money on an Ipower-
You void the warranty on any ballast by opening its case, and no if the fire was caused by "them building, then filling with epoxy" you would see alot of ballasts catching fire, this is general logical assumption; you do realize how many have sold with no feedback issues, taken for what its worth plus the 2 year warranty, and lack of peoples houses catching on fire, I wouldn't really pass them under any other same designed ballast, have you noticed many of the other brands are built in the same country and using the same basic designs on the ballast case, short of buying hortilux which is made in usa, your not going to beable to pass ipower under lumatek or the other chinese manufactured ballasts, I've yet to try hortilux myself but htg and ipower are about the same quality, not extremely cheap but not top of the line by any means. Ive seen plenty of grows under those lights mentioned as well, I'm sure you would see more fire reports if it was an issue.
scary and i was on ebay and noticed an ipower 400wat full kit.... i wont even bother looking next time,,, i hope ur ladies didnt get affected by the smoke. first that smell is shit and it stinks for a few days, and the smoke can settle on the leaves causing burn if left.......
Don't bother looking on ebay much at all then, might as well pay 600 for the 1000w hortilux, there is plenty of retailers outside ebay that sell different brands then the lumatek/ipower 100$ 400w ones, although generally going to cost you 2x more. You get what you pay for.