xyster
10 MW
As I recall, most of the failures happened in a group around 6 months ago. I remember Maytag's 72 volt controller blew at way less than 72 volts. At that time, it was theorized there was a bad batch of FETs going around, or a run of controllers was produced without adequate insulation around the FETs. Even if there was a bad batch, the good batches aren't exactly top quality.
I purchased my 72v35a controller almost a year ago. For most of that time I've run it at 84 peak volts, 80 volts average without problems, without any overheating, or signs of problems. Still, I look forward to replacing the stock FETs with more reliable, more efficient, lower resistance IRFB4110s (and might-as-well increase that current limit while I'm at it... ).
I purchased my 72v35a controller almost a year ago. For most of that time I've run it at 84 peak volts, 80 volts average without problems, without any overheating, or signs of problems. Still, I look forward to replacing the stock FETs with more reliable, more efficient, lower resistance IRFB4110s (and might-as-well increase that current limit while I'm at it... ).