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Discussion Starter · #1 ·
In 1993 Dodge built 54 electric vehicles on the Caravan base. I am working on one of these and wanted to share some things about it and also get some advice which I am seeing that this group does in an exemplary manner.
The TELvan is a real dinosaur of a vehicle. I have a superb service manual and some of the following is fro it.
Traction motor and controller- is a 180v DC (nominal), separately excited (no permanent magnets), brushed, commutated, shunt type electric motor. It is both air cooled and oil cooled.It has 8 brushes. and there is regenerative braking.
Transaxle - is two speed with a clutch for shifting.Reverse is by reversing polarity.
MCU is abig box that also has the charger inside it. It is posted DO NOT attempt to repair. In the past it was decided that the charger was not working ang another was added- mounted in back of van.

Battery pack- there were two types of batteries installed - both 6v - one with NiFe rated at 200AH for first 25 vans and NiCad at 180 AH for the rest. This van is supposedly the later. Both use a KOH electrolyte . The batteries total weight with battery boxes is 1800 Lbs and are located under the vehicle between the frames.
A couple of interesting things with the batteries:
Battery watering system -Uses deionized water and a water deionazion unit came with the vehicle. The batteries are sealed except for two connections to 1/4' tubing. there are 5 water pumps that push water to and through 6 batteries with some sort of valve in battery to keep from over filling the battery. There is a reservoir and hydrogen separation system.
Battery - fan cooling system - 400 cfm fan and duct work to the battery boxes.
Power steering though 180V three phase power pump moto
Heater 8.8KW heater
AC is not working
Has vacuum pump for brakes-I haven't figured out what voltage it works on.

What I am thinking about doing to this van:
Batteries are totally dead and also very heavy- I am in process of removing them. Replacement options are open at moment
I think a lot of things need to be pulled out and more modern units put in.
Motor - I like the AC 51 motor at 144v. with the two speed tranny this seems like a good fit It would make my life easier than trying to get the existing motor and controller working and would probably save a lot of weight.
Heater - I like the idea of a Webasto type forced air diesel heater. I have one in my boat and it has worked for 10 years with no issues.
Power steering - I want some sort of better unit than in there now.
AC- I hate AC as the refrigerant is a green house gas that is much worse than CO2- so maybe no AC

Any way - all is subject to change except the batteries are coming out this week.
My experience - I have built two EV on '86 Mazda pick up . I am good at following instruction and fabricating but I have next to no computer capability.
I also built two 30' Trimarans - last one out of foam core and vacuum bagged CF cloth.

· Registered
46 Posts
Discussion Starter · #3 ·
HPEV says the AC 51 works for vehicles at less than 4000# curb weight. But you are right that it is a bit wimpy. I am only guessing at what the final weight will be but when I look under the hood every thing looks really heavy. I see options to cut weight here but it is a cost issue. The owner has another motor and I think I will weigh that.
The advantage of the AC51 for me is - it is a plug and play unit and reliability should be a lot better than the existing system. I really don't have the ability to work on the existing controller which supposedly has a bad charger in it. The other issue is what the efficiency of the existing motor is.. A number of post seem to say that a series wound is better than a shunt motor.

Are there other motor/controller system that work with this weight vehicle. 0 to 60 was timed in 36 secs by a previous owner.

If I had the skill level of a lot of people on this site I would do what you suggest knowing I can always change it later.

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46 Posts
Discussion Starter · #6 ·
Just a quick update on the 93 Dodge Caravan TELvan.
I pulled out the controller and started testing wiring and sending switches. All the wiring tested good but a number of switches were not working. Bad switches included the low gear, the high gear, the pedal up position switch and the clutch switch. The throttle is suppose to have two pots on it which go to two different controller pins. One pot was totally missing and other tested okay. I replaced the pedal up switch and the pots on accelerator pedal and the two gear switches. The clutch switch is not really needed.
I then hooked the batteries up temporarily and spun the wheels. One of the fronts turned but was dragging. All four brakes were either locked or almost locked- rust and crud . I sanded the rust off the disc and drums and the brakes worked fin. I then put the batteries in the back of the van and went for a test ride. Just a short drive but everything was working correctly.
The batteries are not in final configuration as I don't have the proper bus bars yet. Thare are CNC water jet cut and on there way to me.

Today I was messing around and decided to check out the battery watering system pumps.
This van originally had 30 NiCa wet cells- 54# each. there was a watering system that used 5 pumpr to water all the batteries. These are rather interesting pumps - see pics..I removed the top plate and found this inside. The tubing is a very flexible silicon tube and the cross bar with roller wheels at each end rotates and squeezing the tube pushes the water along the tube. I have never seen a pump like this before.


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