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Discussion Starter #1 (Edited)
Alright, first post.

I am currently contemplating buying an already converted 1985 GMC S15 from my brother. Here is the back story and some considerations.

The vehicle was converted by the local electric authority in Tucson AZ back in the 1993. Not sure why, probably as some promotional thing. The conversion was done by the "Ecoelectric Corporation" in Tucson so I'm hoping it was done well. (If anyone has any info about those people, let me know)

I have some of the schematics for the build, it looks like it is a 120v system, designed to run off of 20 6v Trojans. It has a Curtis PMC(?) motor controller going to an un-named "Advanced DC Motor".

Here are my questions.

1. It's obvious to me that battery technology has improved considerably since 1993. Do I stick with the current plans and go get some 6v Trojans and drop them in? Seems like that would be the easiest solution as all the boxes and connection are already built, but I also want this thing to become my daily driver (30-50 miles/day) so maybe better batteries?

2. I'm also guessing that I might have to look into a new motor controller, and all the electronics in general. The thing has been sitting for about 10 years so not sure if anything works at all. What kind of cost am I looking at for that kind of stuff and what is recommended?

3. I'm gonna need a mentor/someone who knows what they are doing. Anyone know anybody in the Denver area that could help with this? Are there EV clubs, or something like that?

Thanks for looking let me know if you have any thoughts.

Pickupline
 

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... an un-named "Advanced DC Motor".
The specific model is not given, but "Advanced DC Motor" is the brand name, not just an optimistic description. I don't know if ADC (Advanced D.C. Motors, Inc. of Syracuse NY) still exists, but their motors (pretty typical series-wound brushed DC things like the classic "forklift" motor) are still around.
 

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It has a Curtis PMC(?) motor controller...
Here are my questions.

2. I'm also guessing that I might have to look into a new motor controller, and all the electronics in general.
"Curtis" is Curtis Instruments. Their controllers are very commonly used in EV conversions. Since the motor technology hasn't changed in a hundred years, and this is an electronic controller (not some antique gizmo made of relays and resistors), I don't know why you would need to replace it unless it has failed. "PMC" is the general name for Curtis's line of series motor controllers; read the specific model number on the controller to get more detailed information, from Curtis or from this forum. Note that in the Curtis descriptions "pump motor" means a motor driving the hydraulic pump on a forklift, and "traction motor" means a motor which turns the wheel to drive the vehicle (usually a forklift).
 

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The vehicle was converted by the local electric authority in Tucson AZ back in the 1993. Not sure why, probably as some promotional thing.
...
1. It's obvious to me that battery technology has improved considerably since 1993. Do I stick with the current plans and go get some 6v Trojans and drop them in? Seems like that would be the easiest solution as all the boxes and connection are already built, but I also want this thing to become my daily driver (30-50 miles/day) so maybe better batteries?
Yes, batteries have improved, and that's the main reason that EVs are now practical.

No, lead-acid batteries won't likely provide acceptable performance, especially with old motor technology. There's a reason that the electric authority gave up on using this truck, even though they still wanted to promote "clean energy" - the lack of range was probably driving the staff crazy as they tried to get their jobs done.
 

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Discussion Starter #6 (Edited)
More pictures.

It's almost certain now in my mind that I will buy this vehicle from my brother. I just have to figure out how to get it up and running so I can convince my wife that I'm not crazy!

Need to get my brother to remove the strap holding the motor (and covering up the label!) so I know what I'm working with, but can anyone tell from that picture what it is?

Thanks for all the input so far, I'd love to have some more comments/advice. Just getting started with this so I have a TON of research to do, but I'm getting kind of excited.
 

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Discussion Starter #7
Update:

I’m a pilot. I have access to 9 used 24v, 42 amp hour aircraft batteries. Can anyone think of any reason I couldn’t use these to at least get this truck on the road? They are not perfect, but they have some life left and I want to see if I can get this thing moving at least before I invest a bunch of money in a real battery pack. Give me your thoughts.
 

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Motors and controllers are agnostic towards what's causing a voltage, as long as there's voltage. Could be a hamster wheel, if it's generating 120v and can supply enough current, it'll work.

Put 6 of them together in series (~120v) and you're good to go.

The other 3 you can't really use unless the controller can handle 180v. 3 isn't enough to double up the other 6, so, they can just sit around as spares.

Link 'em up and let 'er rip.
 

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I have access to 9 used 24v, 42 amp hour aircraft batteries. Can anyone think of any reason I couldn’t use these to at least get this truck on the road?
Motors and controllers are agnostic towards what's causing a voltage, as long as there's voltage.
Close... how about "as long as the voltage is maintained while supplying current"?

The concern I see is that a 24 V 42 Ah battery can probably only provide a few tens of amps, and even then they probably can't sustain that for long. To completely exhaust the battery in half an hour would only provide 84 amps ideally, and probably substantially less in practice. Forgetting range for the moment (since the idea is just to see it function), if these batteries are used for starting they might be able to put out a couple hundred amps very briefly. So for some examples for five 24 V batteries in series, 70 amps would ideally be 8.4 kW @ 120 V (maybe enough to keep rolling), and 200 amps would ideally be 24 kW @ 120 V (maybe enough to see if it can accelerate), although there will be only one point in the motor's operating range (if any) which would combine the peak voltage and peak current.

Although 9 batteries in series at 24 volts (nominal) each is presumably too much for the controller, it would probably work better to put them in four parallel pairs (or two parallel strings, each of four in series); this would be 8 batteries forming a 96 V 82 Ah pack. For this configuration, perhaps you could get 140 amps for ideally 13 kW @ 96 V, and momentarily 400 amps for (ideally) 38 kW @ 96 V... again only at one operating point, maybe.
 

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Hi
assuming that your brother is going to sell cheap you should take it!

A lot of the work has already been done
 

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Discussion Starter #13
Hi
assuming that your brother is going to sell cheap you should take it!

A lot of the work has already been done
I actually already bought it....$500 bucks!

I just need help getting batteries into it and troubleshooting anything that might be wrong with it. I’m pretty mechanically minded, but don’t know a ton about EV’s. I don’t want to break anything trying to get it running if I don’t have to.
 

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Discussion Starter #14
Alright, so there has been a change of plans with this truck. My wife is decidedly NOT interested in having this thing at our house. So I’m gonna have to sell it. How do I do that and what do I charge? Anyone here interested? Let me know your thoughts. Thanks.
 

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Jeez man, for $500, it was professionally converted, and it only needs batteries...

That's a hell of a deal.

I'm honestly considering (20%) trailing it back into Canada and strapping batteries on it. If the tires roll it's worth that much.

Give the wife another go-'round. Of all the crazy "Guy with a car dream" projects that go on for a decade, this is the most reliable, closest to done, cheapest with not much left to invest project, parts-available-right now, simplest build there could ever be.

For $1600 in batteries you can probably get 45-60 miles of range out of it.

Heck, I'd be tempted to see if any DIY EVers would just lend you a battery so you could take her around the block on it and say "See? SEE? It just needs batteries!"

Maybe just ask a scrapyard (with a case of beer) if you can borrow 10 semi-working starter batteries for a week. Even leave a deposit for the core (~$120 total).

Even just for a fartin' around the ranch truck you shouldn't have trouble selling it... ... ... IF you put batteries on it.

...

*evil grin*

...

Okay so seriously, no one's going to buy an unknown EV that doesn't drive. The only way you're going to sell it is to put some batteries in it to prove it can drive.

So, y'know, while doing what it takes to "sell it and get rid of it" as the wife asked, umm, gee you'll end up having a working EV truck she may change her mind about.

It's foolproof!

Let us know how that works out.
 

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Discussion Starter #16
Jeez man, for $500, it was professionally converted, and it only needs batteries...

That's a hell of a deal.

I'm honestly considering (20%) trailing it back into Canada and strapping batteries on it. If the tires roll it's worth that much.

Give the wife another go-'round. Of all the crazy "Guy with a car dream" projects that go on for a decade, this is the most reliable, closest to done, cheapest with not much left to invest project, parts-available-right now, simplest build there could ever be.

For $1600 in batteries you can probably get 45-60 miles of range out of it.

Heck, I'd be tempted to see if any DIY EVers would just lend you a battery so you could take her around the block on it and say "See? SEE? It just needs batteries!"

Maybe just ask a scrapyard (with a case of beer) if you can borrow 10 semi-working starter batteries for a week. Even leave a deposit for the core (~$120 total).

Even just for a fartin' around the ranch truck you shouldn't have trouble selling it... ... ... IF you put batteries on it.

...

*evil grin*

...

Okay so seriously, no one's going to buy an unknown EV that doesn't drive. The only way you're going to sell it is to put some batteries in it to prove it can drive.

So, y'know, while doing what it takes to "sell it and get rid of it" as the wife asked, umm, gee you'll end up having a working EV truck she may change her mind about.

It's foolproof!

Let us know how that works out.
Well there you go....they can't put anything on the internet that isn't true so I guess I'm just gonna have to gett'r runnin'. I've actually been debating that anyway....I mean she can't move it out of here by herself anyway sooooo....

I'd like to stay married though, so there's that. Where do i find these DIY EVers in Denver that are gonna lend me some batteries? Haven't found any yet.
 

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Discussion Starter #17
So a quick update on this truck. My brother and I were actually able to get it to move under it's own power....not very far, since we were running it off a 12v, but it did move. I'm still debating selling the thing, but if there is anyone in the Tucson area that would be willing to give us a hand getting it back to a daily runner, I'd totally keep it. Anyone on here know a kind soul in that area?
 

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Glad to see you still have it.

Looks like all it needs is batteries. I don't think you need a mentor. Get some batteries, or, ask your questions here, it's likely something we can troubleshoot or help you plan in this thread.
 
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