I wondered if someone can advise me please?
I stripped the batteries on my bike in order to find the dud/damaged cells. The front battery was all fine. I dismantled the three layers, keeping everything in order, not unduoing interconnects and marking each strap connector, leaving everything laid out as dismantled etc.
I've noticed that, when I use a voltmeter across the two terminals of the Anderson connector, I'm getting 66v and this appears to be fine for the number of cells (which were not 100% fully charged when I stripped them) BUT.... the polarity of the connections differs from what's moulded onto the Anderson plug. ie if I put the + ve probe into the bit marked + on the connector and the -ve into - on the connector, I'm getting a negative reading of 66v. If I put the probes in the 'wrong' way round, I get a positive 66v reading?
Have I done something wrong, do you think? I'm 99.9% sure that I've not mixed anything up. I did one battery at a time, left the interconnects on and the straps, laying each tray out from right to left (top to bottom as I stripped them).
I thought I'd better ask for some experienced opinion here, so please help if you can.
By the way..... looking at the Anderson connector on the front battery, the -ve is marked on left hole and the +ve is on the right. BUT the actual current is positive on the left side.
I've checked the voltmeter leads and it's correctly connected up (I used it to test all the cells anyway and they are clearly marked)
Later:
Thinking about it, I think the Anderson straps were put on upside down during manufacture? If they were switched at the battery end, the connector would turn upside down and the + would be positive...... am I right?
Those Anderson connectors are of a "unisex" type, i.e. both connectors are basically identical, so it is of utmost importance that the cables are properly attached to their respective connector so that both together match up polarity-wise. But they can only be put together one way, you can't connect them by turning over just one connector.
I do not know however exactly how the Vectrix cell packs are wired to their respective Andersons. But as the bike probably worked properly before they will be wired correctly with respect to their counterpart...
My rides:
2017 Zero S ZF6.5 11kW, erider Thunder 5kW
Yes. I think basically what's happened is that the Anderson leads/connectors have been mounted 'upside down' on both batteries. Both of them. As you say, they can only fit one way and none of the straps cross over each other, so, when the connector is joined together, everything is as it should be but the polarity doesn't correspond with what's moulded on the halves of the connector because they are both upside down. If the straps on both leads were undone and swapped left to right, the connector block halves would flip over, along with the moulded + and - and then they would correspond with the actual polarity of the leads. If you see what I mean?
Anderson connectors are intended to connect a load to a power source, so they are expected to be used in parrallel connections (positive to positive, negative to negative)
the andersons in the vectrix are in the middle to the battery, so it needs to be wired in series (positive to negative, negative to positive)
as a result, one anderson needs to be wired backwards
Matt
Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km
Thanks very much for that. At first, I thought that, somehow, I'd messed things up!
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Excellent! Thanks for posting that. It's what I have. It's basically the Anderson connector itself being 'incorrectly' marked for this application. That's a handy picture.......