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Discussion Starter · #1 ·
Hi all,
I have the Netgain Controller, and an IOTA 55 DC-DC converter. Short issue: when the headlights are on, the car's power is greatly reduced (by a LOT). I have to use a LOT more pedal before the controller pulls more amps from the battery. I can see the pedal input is increasing, but the battery amp draw is not.

Any ideas why?

I have the negative off the battery wired to a contactor for "key on". The DC-DC converter is wired on the battery side. The positive off the battery is wired to another contactor controlled by the controller. The DC-DC converter is on the battery side of the contactor. The DC-DC converter is thus wired "always on", however, I have the 12 volt output run into a 40 amp relay, and then into my car's 12 volt system.

What is wrong with this setup to cause such a problem?

I'm going to diagnose by eliminating variables (ie: the DC converter), but would like ideas tossed out.

corbin
 

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Can you give us some more info about your EV? pack voltage? number and type of batteries? Size of wiring? What motor? Do you notice this at all speeds or just at highway speeds?

Thanks.
 

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Discussion Starter · #4 ·
Can you give us some more info about your EV? pack voltage? number and type of batteries? Size of wiring? What motor? Do you notice this at all speeds or just at highway speeds?

Thanks.
Good questions, mike! The project is just getting started running. From another thread on conversions there are some details. Here are the specifics:

48 3.2v 200ah Thundersky batteries. Pack voltage: 154 volts nominal.
2/0 wiring throughout.
Netgain Warp 9 motor.

I only have driven short distances. I noticed the problem right away, as it drastically affects hill climbing performance, and there is a hill right outside my driveway. I have not tried turning on the lights at high speeds and seeing if the problem persists.

So far, I have only ever taking the EV to 50mph on the back roads, and have 15 miles logged.

corbin

Project details: http://www.corbinstreehouse.com/blog/category/electric-bug/
 

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Discussion Starter · #5 ·
Ah! Solved, and totally my fault.

There's a purple wire into the controller that is supposed to be hooked up to the reverse lights. I had it hooked up the tail light...so when the lights were on, the controller limits the output. Oh, duh! I need to just hook it up right.

That was the last major bug I had in the system...now its to just "cleanup" the wiring time!
yes!
 

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Hi Corbin... no reason I can think of for you to be experiencing this kind of problem. Can you monitor the 12V supply (say with a DMM plugged into the cigarette lighter or the like) and see if there is truly a correlation between a - presumed - dip in the 12V supply and a reduction in allowed power?

Also, what happens at full throttle? Do you see a reduction in allowed battery current, motor current or none of the above - in other words, can you still reach maximum (programmed?) amperage at full throttle, it just takes longer to get there, or is there a reduction in either or both amperage limits?

Finally, have you contacted NetGain Controls about this exceptionally strange issue? I know it's Sunday, but maybe they are like me and work 7 days a week??? :D

(leaving for posterity, but, problem solved apparently ;) )
 
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Ah! Solved, and totally my fault.

There's a purple wire into the controller that is supposed to be hooked up to the reverse lights. I had it hooked up the tail light...so when the lights were on, the controller limits the output. Oh, duh! I need to just hook it up right.

That was the last major bug I had in the system...now its to just "cleanup" the wiring time!
yes!

One of those Doh! moments? Hey, it's great to hear you have your vehicle up and running. Glad you figured it out. So you put yourself into reverse cut back mode. Good find. Hows that controller? Hows the power output? Can you put rubber on the ground? Get some video and by all means get some photos after you clean up the wiring.

Great news.

Pete :)
 

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Discussion Starter · #8 ·
One of those Doh! moments? Hey, it's great to hear you have your vehicle up and running. Glad you figured it out. So you put yourself into reverse cut back mode. Good find. Hows that controller? Hows the power output? Can you put rubber on the ground? Get some video and by all means get some photos after you clean up the wiring.

Great news.

Pete :)
Yeah; I appreciate everyone helping out on the forums - it has really helped me get through the project.

The soft reverse seems like it will be a nice feature..once I have it wired up.

The controller seems great! I have it limited at 500amps out (less than 3c). I might up it to 600 (3c) at some point. I have hit the 500amp limit during a hard acceleration in second to see what it could do; the controller seems to act sort of strange at the limit -- it kind of makes the car buck a little, almost as though it cuts back past the limit instead of just holding it there. I'll have to test more though and see.

I haven't dared to hit the pedal to the ground yet from a cold start. I'm still taking it easy on my stuff as I work out the bugs. The pack isn't at all balanced yet...I want to first get it somewhat balanced.

There's a slow initial drive video on my website..nothing fancy! I'll post a walk through of the components soon. Then more vids..and pictures.

Right now I'm sitting outside in the cold watching cell voltages as I do my second charge.

corbin
 

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Discussion Starter · #10 ·
Nice Bug! It's very clean and classy looking. The silent electric drive really complements it. When you get it sorted out, slick your hair back, throw on a white t-shirt, with a fake pack of smokes rolled up in your sleeve, and go cruisin'! :D
Yeah, definitely! My original plan was to chop the top and make it a cool chopped car...but in the end, I decided to not do it, as it would have taken me at least a year to figure out how to chop and get it back on right.

corbin
 

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Yeah, definitely! My original plan was to chop the top and make it a cool chopped car...but in the end, I decided to not do it, as it would have taken me at least a year to figure out how to chop and get it back on right.

corbin
Probably a smart move. Chopping the top is one of those modifications that opens the "since I went this far, I might as well..." can of worms. I tend to live there, and it takes an incredible amount of time and energy to work your way out to a conclusion after those decisions.

I think Plug Bug looks great like it is, and you can actually enjoy using it soon. ;)
 
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