Re: range complaints?

[XURQ03A@prodigy.com ( LEE A HART)]

Eric Chang wrote:
>My real problem with the electric car is that it is unreliable...

This can happen with new technologies. Companies with no real experience
slap together a conversion, and let the buyer sort out the problems. The
buyer is also ignorant, so perfectly good parts rapidly degenerate into junk.

But EVs can be extremely reliable. That's why they are so popular for
industrial and commercial users, who are fanatically concerned about cost
and reliability.

>First it was the controller...

Controllers are extremely reliable when properly applied. But there are
also examples of controllers that die almost immediately. It usually turns
out that they were misued or overloaded.

Electronics usually fail suddenly when you cross that invisible threshold
(too hot, too much voltage, or too much current). The trick is NOT to run
the controller at its maximum ratings, but derate it sufficiently so there
is a safety margin.

This means you shouldn't use a 120v controller in a 120v EV. Just after
charging, the battery voltage could easily be 144v. Use at least a 144v
controller so you have a safety margin.

Likewise, don't run the current limit wide open; turn it down a little. It
costs a little accelleration, but gives you a safety margin for much better
reliability.

And provide adequate cooling. Electronics hate heat. If it's too hot to
leave your hand on it, it's too hot for the electronics.

>Then, the batteries died.  They did not die slowly and quietly,
>but instead they died suddenly and violently...

This is not typical, but it does happen. The usual causes are bad
connections, negligent maintenance, and abuse. The high current connections
have to be made correctly, or they will overheat and fail. Small firms and
beginners with no experience often don't know how to do this.

You (or your mechanic) need to measure the voltage drops, or check for heat
buildup occasionally to know if the the connections are made right, and
stay right. It's part of routine maintenance, as is checking and adding
water for flooded batteries.

Negligence and abuse are the other battery killers. Typical problems are
low water levels, excessively deep discharges, and improper charging.
Sometimes it is deliberate; racing, trying to see how fast or how far it
will go, cheaping out on the charger, etc. Sometimes it is accidental; the
user doesn't know any better. Many EVs have inadequate instrumentation so
the owner can't even tell what is being done to the batteries.

>Because of the voodoo engineering that the car was put together with...
>It was incredibly difficult to remove the motor.

If not abused, the motor will last a long, long time. But it still has
brushes that will eventually need to be inspected and replaced. Fitting it
into the car like a chinese puzzle is a sign of bad engineering.

This is a classic problem with hobbiests or small companies with limited
experience. Conventional wisdom says, "Do it right the first time." This
implies that you'll never have to do it again, so it doesn't matter how
difficult it is to fix.

This is nonsense. The only possible way to do it right the first time is if
it isn't really the first time -- you already have prior experience.

The correct attitude is, "Plan to build it twice." Make it easy to
disassemble to replace anything. Only use parts for which spares are
available. Document everything.

>Many people recommended that it be taken to a motor rewinding shop.

I agree with Paul Compton; it sounds like you went to the wrong shop. Get
your motor back before they make a bad situation even worse!

It is very simple to take these motors apart. Any shop that knows what they
are doing can tell almost by inspection what needs to be done. And they
will have the equipment to see if the windings are shorted, open, or
otherwise need repair.

Like any business that you are unfamiliar with, get references. If they
can't give you the name of a satisfied customer who had the same sort of
motor repaired, go somewhere else.

Hang in there. Consider that you are getting an education at the School of
Hard Knocks. It's an expensive school, but very good (if you pay attention)!

Lee Hart                     If you would not be forgotten
4209 France Ave. N.          Soon as you are dead and rotten
Robbinsdale, MN 55422 USA    Either write things worth the reading
phone (612) 533-3226         Or do things worthy of the writing
e-mail XURQ03A@prodigy.com   (Ben Franklin, Poor Richard's Almanac)