Thursday, March 12, 2009

Charge Detector Blown Again

A few days ago, something funny happened to the vehicle. I drove home and my LVP light came on earlier than I expected. When I got home, the front battery was rather lower than the others in the pack. I attributed this to being just behind the front grille where a lot of cold air is blowing in. to remedy the problem a bit, I slide a large sheet of foam-core board between the batteries and the radiator grille which gives a bit of insulation and forces the air go around the side.

After measuring my batteries for several days after that, they seemed much better, but still didn't seem to get fully charged when sitting at work. Again, I attributed that to the low temperature around here (mid 30's).

Today, I drove home, plugged in the charger and just checked to see if the charge detector was working. Sad to say, the FET has probably blown open again since the OVP lights were not on and lots of current was dumping through the large external 3-ohm charging resistor, making it really hot. This would definitely explain the slow charging.

After trying to fix this device several times, I have a few options:

- fix it again (and wait for it to blow again)
- send the charging system back to Belktronix to get upgraded to a Gen2 system without the charge controller for about $400
- dump the Belktronix system altogether and go with something else, like individual Soneil chargers (Rob Connelly did this and is happy with the results)

I'm not sure what I'm going to do. The existing charger works, but it's just a bit slow. I'll ponder this over the weekend. I have an OEVA meeting to lead this evening.

Ugh,
Tim

2 comments:

BTX said...

Hi Tim,
Bryan with Belktronix, replying to your blog entry regarding the again-failed Charge Detector issue. I really didn’t know where to start about this recent problem you have with it, but I want to assure readers that there is way more behind-the-scenes information that is not being disclosed in this blog regarding this problem. The situation I find here is when new readers who click in today without knowing the history or the behind the scenes information miss out on some important details that got us here. It’s those details that can misrepresent the facts and leave them with the wrong impression about the system’s reliability. For those who have followed the blog in detail, sorry for the rehash. So, while I'm sorry to hear you're having trouble with the Charge Detector yet again, I have to say, when I read that it failed on your blog the first time, it was still under factory warranty, and it would have been repaired for free. Instead of sending it in to be repaired you decided to repair it yourself. You mentioned that the Mosfet had failed and you replaced it. Did you replace it with the same P/N Mosfet? Things like gate charge and Rds-On voltage affects the way the unit performs electrically and thermally. You also indicated that you changed some resistor values on the board, but neglected to tell me what they were. There was never any communication as to “will these changes work”? Nor is this the first time whereby I found out about an issue or problem on your blog without any email notification from you that one even existed. Usually I would just take it up with you personally and resolve the issue and possible prevention scenarios. And on one occasion you did make a small mention of it on your blog. Now I’m finding that this is your preferred method of communicating problems about the system, so I choose to reply to you on your blog instead. If a part fails under warranty and it is my fault, then surely I'll fix it. Even when I’m not at fault, I’ve gone out of my way to make things right. But you’ve chosen this forum to point out failure of a part that I didn’t even fix, now to make it a reliability issue as to include in your text you are considering to ‘dump the Belktronix system and go with something else’. So now blame has been pointed my way for you having to fix the problem over and over again.

The initial problem had been a crossed wire somewhere leading to a battery monitor failure, which was repaired. Next was fluid intrusion on a Battery Monitor that is spray sealed and at best, water resistant, not waterproof. That led you to charge that battery with a separate power supply since the monitor had been electrically compromised, introducing a large imbalance into the battery pack. This likely caused the charging system to throttle at the onset of the bulk stage, driving the Charge Detector past its thermal capability into failure. Then with your repeated repairs to the Charge Detector, only to end in frustration, and in finality, insult. I’ve gone out of my way to accommodate you in your EV buildup, to the point of locating a tach for your vehicle, and making the interface to limit system RPM’s, for little out-of-pocket on your behalf...

Despite all this, I still endeavor to make every Belktronix EV installation a successful one, regardless of the obstacles encountered, and I will put in the effort to make it happen. Its not a simple task to offer an EV Electronics kit that makes the transition from gas to electric, otherwise I would have been at the end of the list of companies who offered one. Successful EV kit installations mean something to me personally. Its as if I am there in the process, knowing that I was a small part in getting one more EV on the road. And product improvements are sure to come over time.
So while GM and others are considering offering a BEV to the general public, who knows how long that will take or how much it will cost. And with LiFePO4's bringing into reality a 100 mile / charge, an EV system is certainly something to pursue. I point I want to make to new readers is there is more to the story that what shows up on a single blog page. Have a good day,
Bryan

TimK said...

Hi Bryan,

Thanks for your comment. I acknowledge all the points you brought up. It can be misleading if someone who just reads this one blog entry to get the wrong impression about the situation. Your tech support has been very responsive during the course of our interactions.

Regards,
Tim