Car Charging

[Colin]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> The most reliable electrical component is the one that isn't there! </div></BLOCKQUOTE>

Pretty much goes for any system on the car Z, not just electrical . "Electrical Failures"� are often blamed for DNF's but I bet you'll find 99% of the time it's the wiring and not the component. If you brake an A-Arm you don't blame the off the shelf spherical bearing you blame the bloke who designed\manufactured the A-Arm but as soon as a starter motor doesn't turn over everyone point's the finger at it rather than the bloke who thought it would be a good idea to run 22 gauge wire to it to save weight. If as much design went into the loom as goes into geometry then "Electrical Failures"� would be very rare

[MikeWaggoner at UW]

I always thought it'd be pretty easy to 'fool' the charging system into thinking it had more voltage whenever you had the throttle over say, 80% so it wouldn't charge. The load would be higher at lower RPM's, but you'd get ok charging and the same peak power as if you had no alternator (except no rotating mass advantage like you get from scrapping it).

[Z]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Colin:
"Electrical Failures"� are often blamed for DNF's but I bet you'll find 99% of the time it's the wiring and not the component. </div></BLOCKQUOTE>

I remember hearing (from an UNreliable source) that "electrical failures" are something like; 50% connectors, then in decreasing order of occurance, wiring, sensor failure, electronic (solid state) components, and lastly electrical motors/coils/etc.

Z

[Colin]

yea, that sounds reasonable Z, but I reckon wiring (including wiring at connectors) would account for more failures than that at FSAE in particular.

As for "'fooling' the charging system"� mike, remember the alternator only works has hard as it needs to that's what the reg's there for.

[Gabriel Descamps]

It IS true. I´m not sure wiring is 99% of the problems. However, I AM sure it IS 100% of the problem. The least connections you have, the better. The more connections you have, the more sources of failure you´ll get.

You should use AWG 20 wires, it´s the lightest you should use.... As for the starter, you should try AWG 12 (that way you´ll be ensuring enough current goes for the starter, which uses A LOT).

The car WILL start without the alternator, however, the battery won´t last very long.

Building a reliable wiring system is tough, but not impossible. Just make sure nothing´s hanging out, and that everything´s protected from water. Also avoid black tape and the sort, and never make a connection between two wires without a connector (like a knot or something).

Also, don´t let any Mechanic Engineer near it Wires, well, they just don´t come naturally to them.
(Just kidding guys)

Good luck with that.

Cheers

[Chris Boyden]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">If as much design went into the loom as goes into geometry then "Electrical Failures"� would be very rare </div></BLOCKQUOTE>

Very true and very necessary given the complexity of the fuel injection systems.

I agree that connectors probably account for more electrical failures than any other part of the electrical.

A proper crimp with a ratcheting aerospace quality crimper is definitely worth the money.
While most teams don't want to spend the $250 or so on the nice crimper, I sleep at night knowing that the connections it makes aren't gonna fail.
Milspec or Deutsch connectors are also definitely worth the money. Soldering can work well too, but I worry about the "hardening" effect soldering has on the multistrand soft and flexible copper. If you solder, make sure and strain relief the wire from the connector to prevent the solder joint/wire from work hardening and breaking. Several connector systems offer shrink boots that will provide waterproof strain relief and look nice. A decent connector system also makes it easier to design and wire the car electrical and makes the whole job more reliable and more professional. Waterproof connectors are also a nice touch, especially since it's so dry in Michigan during comp.

Anyway, what does this have to do with charging systems?

[Cement Legs]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Gabriel Descamps:

Also, don´t let any Mechanic Engineer near it Wires, well, they just don´t come naturally to them.
(Just kidding guys)

Good luck with that.

Cheers </div></BLOCKQUOTE>

Another electrical engineer who thinks setting up his new surround sound stereo counts as a co-op term....

[Gabriel Descamps]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Another electrical engineer who thinks setting up his new surround sound stereo counts as a co-op term....
</div></BLOCKQUOTE>

Nah, not electric, electronic....

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Anyway, what does this have to do with charging systems?
</div></BLOCKQUOTE>

And well, about the charging systems. Why mess around with it? Alternator works just fine, just plug the thing, use a small battery (7-8 Amp-H), and it should work fine. I wouldn´t look into complicating already complicated things.

[Engine Dude]

My Chassis dude is making a full (Straight tub)aluminium monocoque and thinks the engine is too wide.

Being asked to look into a external altenator and run a drive system off the end of the crank or the diff. The rotor weighs a bit though and someone else posted balance issues could arrise. In all honesty it looks like a bit of messing about for little (space) gain.

Cheers

Sam