I have EC5s on all the batteries. I use EC5s because they'll carry a
*lot* of current, they solder on easily, you add the plastic housing
after you've soldered it (so you won't melt the plastic while you're
soldering) and they plug in and unplug without needing a big fight.
Female on the batteries (and things offering power) and male on the
things accepting power. They are impossible to plug in the wrong way
round; you can't plug a negative into a positive, if you soldered the
plug up the right way round.
The resistor in the
circuit means that as soon as it's plugged in, the batteries slowly (a
couple of seconds) charge up the capacitors in the controller, so you
don't get a big spark. That saves the contacts on the switch. The switch
is a domestic contact breaker, rated at 53 amps (so it should switch
power off if there's a short circuit). £2.79 on Ebay,
http://www.ebay.co.uk/itm/Gewiss-Series-90-GW-92-MT60-Type-B-Single-Pole-MCB-/180950744687?pt=UK_BOI_CircuitBreakers_RL&var=&hash=item2a21813e6f
But I don't rely on that, there's a 40 amp fuse (it's a car blade fuse, costs £1.10 on Ebay).
http://www.ebay.co.uk/itm/LIQUID-ICE-14-GAUGE-AWG-IN-LINE-STANDARD-BLADE-FUSE-HOLDER-CAR-BIKE-BOAT-BIKE-30-/400591678378?pt=UK_BOI_Electrical_Components_Supplies_ET&var=&hash=item5d451febaa And, of course, I have a few spare fuses, which I carry in my puncture repair kit.
The
shunt needs to be 0.75 milliohms. That's four inches of 10 AWG wire,
you can work out how much you need if you use a different guage from
this: http://www.powerstream.com/Wire_Size.htm. The ammeter/voltmeter sits on the handlebars, so I can see at any time, how much current I'm pulling, and the battery voltage.
The ammeter/voltmeter is from Ebay, £3.59
http://www.ebay.co.uk/itm/LED-Digital-Volt-Amp-2-in-1-Panel-Meter-Voltmeter-Ammeter-100V-100A-Blue-Red-/161224223929?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item2589b66cb9
The
wattmeter is Ebay
http://www.ebay.co.uk/itm/Digital-LCD-DC-60V-100A-Balance-Voltage-RC-Battery-Power-Analyzer-Watt-Meter-/201051715341?pt=UK_ToysGames_RadioControlled_JN&hash=item2ecf9db70d,
expect to pay between £8 and £9. I have that down with the batteries,
because it's easiest to put it there. I use it to tell me how many
amp-hours the battery has done since being connected up. I use 5ah
batteries, and I'm getting 4.5 ah or so. The batteries will slowly
deteriorate over time, so when they only give me 3ah, I'll replace them.
The
"battery to power voltmeter/ammeter" is a holder for four AAA batteries
with a little switch. I run it until the AAA batteries are dead, then
recharge them - this means that I could be without my ammeter/voltmeter
display for a little while.
The series connector is
just two EC5 males in series, connected to an EC5 female. It's just as
easy to wire up three or four, depending on how many batteries you want
in series to drive your bike.
As well as all the
usual wiring on the bike, I have an ethernet cable going from the
battery pack to the handlebars. That has 8 conductors; four are for the
ammeter/voltmeter, two for a 5 volt power supply that feeds my PDA
(which I use for navigation) and the other two will be feeding a
headlight when I install it. The 5 volts comes from a step-down unit
that runs from the bike battery, and the headlight will also be fed by
the bike battery.
Here's the diagram.
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