Friday, 13 March 2015

Battery testing continues now that spring is finally here :-)

So I have recently gotten back out to my workshop to try and pick up on the battery testing again, there has been a big break from this due to the shitty English weather over winter and other time pressures, but with only 6 months to go before I need the RX8 (which is barely started) I need to get a move on.
I have done a few cell tests recently but have not as yet gotten back into the swing proper, just prepping the rig so that I can easily swap out cells and test 2 every 30 minutes or so has taken some time, plus the blow up of my decent Antec PSU hampered the charging situation somewhat, I have now completed charging all of the cells ready for testing (other than a few failures that need retesting, failed due to random setup failures that are not necessarily problems with the cells) 

“Honey I blew the Gearbox”

Ok so speaking of failures in my last few posts here comes another!
Yes I can now confirm that my adolescent driving style over the last year and a half has finally taken its toll on the tiny little Honda Beat gearbox :-(

After driving over the mother in laws the other night I hear the dreaded “pop” and grinding of teeth once again (barley a month after this happened before) except this time I was literally and coincidentally driving past my mechanics workshop so it was a simple matter to roll it round the corner and park it up for Brent to look at ASAP.
He got around to it a couple of days later, however this time the news was not good, I had stripped the splines from the old clutch plate that we had used to make a coupling plate from and it has also worn the splines on the gearbox as well, so a new gearbox and clutch plate are in order.

You can just see from this blurry photo that there is a distinct lack of splines in that there hole :-(

We have source a replacement gearbox and clutch plate and should hear on this Monday coming from the guy who is selling them.

For now I am back car sharing the deep fat fryer :-(

Meltdown on the Powerlab!

Here comes another failure! I was picking up on the testing rig the other day and after starting a test smelled the bad smell of burning plastic, I began checking over all the battery connections with my nose looking for the source and then the charger quit with “Banana plugs disconnected” during the test. Checked the plugs and sure enough the negative terminal on the Powerlab 8 had melted! Bugger.
Luckily I had a stack of these sort of banana sockets (albeit for old school jacks) that just so happen to be a perfect fit, and after investigating an exact replacement I discovered that they were originally of a distinctly poorer quality than the ones I had in stock, Also luckily my partner had a kids birthday party to attend with our kids so I managed to find a couple of hours to affect a repair (and a pretty nice one at that) Confident that the issue was resolved I went straight back to testing, Successfully now the melted plug has been replaced, I replaced both the –ve and +ve connectors just for ascetics reasons and made a much better mechanical connection that the poor soldered connection that were present originally.
I think the reason for the meltdown was due to the fact that my battery testing rig has a set of buss bars that are connected via banana plugs to the Powerlab 8 which means that I am not plugging and unplugging the banana jacks after each test (as you would normally if you were just testing a single cell pack) so any degradation of the banana jacks was not being noticed until it caused a problem (i.e. melted) So in order to prevent the same happening again I replaced the faulty banana jack plug with a shiny new one (stripped from a dead cell pack) and cleaned the banana jacks pin with wet and dry paper. I will just have to check the jacks more often between cell tests.
I can honestly say that if there is one thing I have learnt (the hard way) it is that the most common cause of problems with HV EV tech is bad electrical connections.