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does the precharge relay stay closed during running???? i have my main(-) contactor wired to the precharge relay circuit. so maybe after the VCU sees everything is good it drops the precharge relay? if so this would also drop my main(-) relay and i would not have a circuit anymore.....

or does the precharge relay stay closed during running?

shnitzel
While I definitely don't know how the Thunderstuck circuitry works, I drop out the pre-charge just after energizing the main + contactor. The (-) contactor remains on, so the circuit stays complete, till requested to power down. It would be a waste of power to leave the pre-charge relay on. My guess is they turn it off.
 

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does the precharge relay stay closed during running???? i have my main(-) contactor wired to the precharge relay circuit. so maybe after the VCU sees everything is good it drops the precharge relay? if so this would also drop my main(-) relay and i would not have a circuit anymore.....

or does the precharge relay stay closed during running?

shnitzel
That would probably do it. The precharge contactor only stays on during precharge. I have my negative contactor wired to key on, and the positive and precharge contactors controlled by the VCU.
 

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Discussion Starter · #24 ·
winner winner, now i will have some chicken dinner! wired the main(-) relay to the ignition toggle and it retains voltage after precharge. runs smooth!

it will rev up in forward and slow down when i release the pedal. the brake switch works and stops the motor when in forward.

however, when in reverse i release the pedal and the motor keeps spinning at constant speed. even if i press the brake switch.. it keeps spinning at a constant speed like cruize control. only way to stop it is to switch it off.

it works as you would predict in forward gear. but reverse wont stop.

so i will research that now and the Leaf BMS. while i rig this motor into place!!!

thanx for your help, i now have a running bench test!

shnitzel
 

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Discussion Starter · #25 ·
Thunderstruck tells me:

"Reverse has no regen. When the motor is in reverse idle or neutral it does some interesting coasting action without any regen. In the vehicle you will have enough parasitic drag to slow it down."

so then its time to figure the driveshaft out and the battery bms.

onward!

shnitzel
 

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Thunderstruck tells me:

"Reverse has no regen. When the motor is in reverse idle or neutral it does some interesting coasting action without any regen. In the vehicle you will have enough parasitic drag to slow it down."

so then its time to figure the driveshaft out and the battery bms.

onward!

shnitzel
Well, that makes perfect sense, then. Very good! I doubt you’ll be able to use the Leaf BMS, and you may have to crack the pack open to wire up some sensing leads. I’ve used the TSM BMS, and I’m happy with it.
 

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Discussion Starter · #27 ·
im about to start the next stage of my project. had to "put out some fires" at work for a bit. now im back to my stuff!

i want to mount the leaf motor and inverter on its side. with the cooling lines all facing up. i dont see any reason why not. anyone see why not???

i have my coupler to mount the driveshaft directly to the motor almost done. if this all works out on the first little test drive i'll invest in the lower 7.4 : 1 gears that are available for the 9" ford differential.

i have enough battery charge to get around the town a few times no problem. so ill get a few test runs up and down the block done with the charge i have (about 90% im guessing)

i still dont have a working charger. i will figure that out last after i get it rolling on its own.

so my last question is about the BMS again.... does the bms not balance the cells when the battery is not connected to the car? what functions if any does the bms do when not connected to the canbus? would it balance during charging? when sitting in storage? or not at all?

thats my progress and questions for today.

shnitzel
 

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Where'd you get that ring & pinion? Highest I've seen in my recollection, and used, is 5.14
Often aftermarket suppliers have ratios (for any common axle or final drive) beyond anything that was available OEM. I was looking at available ratios for the Ford 8.8 (for another project) and found similar ratios.
 

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Thanks Shnitzel.

I wish that was the case for my C5 Z06 on gears that deep, Brian...

Precharge circuit, IMO, should also serve to discharge the caps when you power off, for safety -- having been lit up by a charged 450V cap on a tube radio I was building, I can say you really don't want holes punched in you from the zap when you thought the power was off, lol.

Having it on during running is pointless, as your precharge resistor gets shorted by the main contactor, in any case.
 

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Discussion Starter · #32 ·
im just "slightly" concerned about driveshaft rpm.... well play that by ear. maybe literally. ha ha ha.

i did check the voltage on the system after shutdown and it quickly drains back to 0v. i also have high voltage gloves for reassurance. keeping as safe as i can! thank you for the pointers.

im hoping that the nissan leaf stock bms will do something for me. even if it only balances when charging. or at all. from what i read people are hacking into the batterys through the canbus and checking individual cell volts. if this is possible then i can at least check my individual cell voltages and keep an eye on them. i best do this before i do any miles with it.

anyone think im silly to mount this motor sideways?

shnitzel
 

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You mean like the output shaft running front to rear? I can't think of any reason not to.

It's long past time for some photos, friend...
 

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I wish that was the case for my C5 Z06 on gears that deep, Brian...
While Corvettes always use lots of components from the GM parts bin, the C5/C6/C7 transaxle is unique enough that I'm not surprised that there isn't much aftermarket choice - it doesn't use a final drive shared with any other model (even though the transaxle are based on the common T56 and 4L60 transmissions), and the pinion shaft is downright oddball (due to the unusual configuration). Much lower gearing is not likely to be wanted for many people using that transaxle, and the pinion shaft design may limit how small the pinion can be (and thus limit the ratio) but I understand the frustration. Apparently you can only get 4.11:1.

In contrast, the Ford 9-inch came in everything from family sedans to Mustangs to pickup trucks, and is used in both salvaged and aftermarket forms for everything from rock crawlers to drag racers. There's something to be said for using common stuff, even if it isn't very advanced.
 

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i want to mount the leaf motor and inverter on its side. with the cooling lines all facing up. i dont see any reason why not. anyone see why not???

i have my coupler to mount the driveshaft directly to the motor almost done. if this all works out on the first little test drive i'll invest in the lower 7.4 : 1 gears that are available for the 9" ford differential.
You mean like the output shaft running front to rear? I can't think of any reason not to.
If I understand this correctly, the motor would be mounted with the shaft longitudinal (no reason not to do that), but without the reduction gearbox (because the motor shaft drives the axle's pinion shaft directly); the "on its side" part means rotating the motor around the shaft axis so that the inverter is to one side instead of on top... presumably to make room for other components above the motor. This likely won't matter to the motor (because the bearings are greased so oil drainage doesn't matter) or to the electronics (of course) or even to the cooling (because gravity isn't relevant to the pumped flow).
 

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Discussion Starter · #36 ·
exactly brian. i see no reason why not mount on its side. thats the plan then!

i got the driveshaft coupler almost finished. local machinist charged me $20 to make the fiat clutch center fit into my driveshaft end. that may be the only real custom part i need to build!!!!! im loving how easy these electric conversions are.. i may NEVER build another gas car..... ive done lots of turbo cars... sooooooo much work....

i havent done anything really photo worthy since the last photos. when i get the motor mounted ill do more photos. i dont use / own cameras or phones, so its a special day when i use a camera! ha ha ha.

so my last real unknown is the leaf bms. as youve told me i probably wont make it useful... but im having a hard time understanding that its not functioning anyhow...

shnitzel
 

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exactly brian. i see no reason why not mount on its side. thats the plan then!

i got the driveshaft coupler almost finished. local machinist charged me $20 to make the fiat clutch center fit into my driveshaft end. that may be the only real custom part i need to build!!!!! im loving how easy these electric conversions are.. i may NEVER build another gas car..... ive done lots of turbo cars... sooooooo much work....

i havent done anything really photo worthy since the last photos. when i get the motor mounted ill do more photos. i dont use / own cameras or phones, so its a special day when i use a camera! ha ha ha.

so my last real unknown is the leaf bms. as youve told me i probably wont make it useful... but im having a hard time understanding that its not functioning anyhow...

shnitzel
hey you may want to take a look at open inverter forum they have all the info you would need to get the nissan bms working.
 

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Discussion Starter · #38 ·
good to know that the bms is possible. i have glanced at openinverter but havnt signed up yet. i also see uksouthwestev has the leaf dc-dc converter and charger running now. so im hoping to follow his lead!

for progress:::

all the stock stuff is out. even the 165lb cast steel weight hiding over the gas tank. thats more than the motor and inverter right there! ha ha ha

i have pulled the battery up into place between the front wheel wells. its a little high but i plan to take my 3/4" plywood shim out. then hopefully the seats sit well enough over the battery with room for me under the steering wheel.

the motor / inverter stack doesnt fit nice so im just mounting the motor seperately from the inverter. i bandsawed the extra aluminum off the motor giving me access to a flush front mounting surface. i am going to trim the tranny crossmember some to fit the motor right where it needs to be. i dont want to modify the driveshaft. im just running it stock which is very short. this hopefully will help me through the high rpm wiggles ;)

i pressed in new heavy duty u-joints into the driveshaft. its all greased and ready.

the fiat clutch center has been machined to press fit inside the ford driveshaft splines. i still have to drill and tap the motor shaft for a big bolt. i hope the steel is manageable. if it survives a few trips up and down the block i will locktight the hell out of it splines and all and hope it stay in place.

getting the motor mounted in place with the driveshaft installed should be easy from here.

so here are my new questions / concerns. i have separated my motor from controller now. am i best to source a 2010-2012 motor wire harness for it? would the 2010 3-phase wiring seal to the 2013 motor? or should i just build some short copper busbars to stick into the motor and connect the 3-phase wiring to?

i also need another round connector for the 2016 battery. i need to source one of those to permanently wire this thing. any idea what its called or where to find it? its the one where i tap into the precharge and relay circuits on the traction battery.

if i can get the motor wired to the inverter and the circular battery plug ill be rotating tires soon!

shnitzel
 

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Discussion Starter · #39 ·
I made a couple little videos to catch you guys up. the first is a basic overview. and then i linked a "channel" where i will keep posting as i progress.

to date everything is in position and the motor is mounted in place. still some bracketry to build before a test drive. but im progressing!

<iframe width="560" height="315" src="
" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>


hope you enjoy!

shnitzel
 
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