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Chapter 10: Electric Vehicle Conversion 263Battery WiringThe most important consideration in battery wiring is to make the connections cleanand tight. Figure 10-32 also shows both front and rear battery packs in their wired-upcondition. Check that you haven’t accidentally reversed the wiring to any battery in thestring as you go. Double-check your work when you finish, and use a voltmeter tomeasure across the completed battery pack to see that it produces the nominal 120 voltsyou expect. If not, measure across each battery separately to determine the problem. Ifreversed wiring was the culprit, the correctly installed and wired battery should fix it.If a badly discharged or defective battery is the culprit, check to see that it comes up oncharging and/or replace it with a good battery from your dealer. A recharged “deadbattery” will shorten the life for the entire battery pack. Please be careful to check all ofthe batteries. Important: Make sure that the main circuit breaker is off before you connect thelast power cable in the battery circuit. Better still, switch the main circuit breaker off and waituntil the system checkout phase before final battery connection.Accessory BatteryThis is also the time to mount your 12-volt accessory battery. Jim initially used the 12-volt starter battery that came with his conversion chassis (see Figure 10-35) for tworeasons: it allowed him to do component testing during the wiring phase, and it wasalready mounted and wired in place (saving him a few steps). Figure 10-35 (top) showsthat the inside of Jim’s “magic box” is now down to two power cables (the leftmostcable’s battery destination is now clearly visible) and two instrumentation cables. Figure10-35 (bottom) shows the outside of Jim’s magic box with the cover in place installed inits initial location.After ConversionThis is the system checkout, trial run, and finishing touches stage. First, make sureeverything works, then find out how well it works, then try to make it work even better.When you’re satisfied, you paint, polish, and sign your work. Let’s look at the individualareas.System Checkout on BlocksJack up the drive wheels of your conversion vehicle (or raise them up on work stands)for this phase. The objective is to see that everything works right before you drive it outon the street. With your vehicle’s drive wheels off the ground and the transmission infirst gear, do the following:• Before connecting the last battery cable, verify that the proper battery polarityconnections have been made to the controller’s B1 and B– terminals.• Obtain a 100- to 200-ohm, 5- or 10-watt resistor, and wire it in place across themain contactor’s terminals. With the key switch off but the last battery cableconnected and the main circuit breaker on, measure the voltage across thecontroller’s B1 and B– terminals. It should measure approximately 90 percentof the main battery pack voltage (in the neighborhood of 108 volts) with thecorrect polarity to match the terminals. If this does not happen, troubleshoot thewiring connections. If it does, you’re ready to turn the key switch.