[skooler]

Bargain!

watching with interest

[mmoyer2655]

Quick question:

I'm trying to figure out if I need, and how to use relays in my car. I've seen people use them to power on the vacuum pump, controller, and contactor.

My question is why I need them? Why can't I just wire each device directly to my 12v ignition source (switch)?

And if I need them, which type do I get (if anyone has a link that would be great). Do they need to be 12v to 12v relays? 144v to 12v relays?

Thanks for the help!

-Mike

[Jesse67]

If the amp load isn't too high you can certainly wire and switch any 12V accessories directly but it depends on the item.

For a vacuum pump you probably want the vacuum switch which cycles the pump on and off to go through a relay and not switch the pump on directly as the vacuum switch likely can't take that kind of load. A standard 12V 40A automotive relay can be found at most parts stores for ~$5 or so and will work great for any 12 accessories.

If you want your car to start like a normal car, as in you have to turn the key to start to get it to turn on as opposed to it starting when you just turn the key to run then you need a standard 12V relay that is powered by the start 12V signal to latch on. Once the relay gets 12V from the start circuit the switched side provides power to the coil which keeps it latched and on until the key turns to off. This relay will provide 12V power to your contactor and controller if it needs it. You should be able to get a wiring diagram for the soliton which will help you out a lot.

What you need depends on your controller and your preferences. Doesn't the soliton have a built in contactor? Were manual brakes an option on a 92 celica? Then you wouldn't need a vacuum pump. If you just want the car to start when the key turns to run and not worry about the start circuit then you don't need that either. Check out the wiring diagram for the soliton.

Good luck!

[Jesse67]

Read this cover to cover, explains a lot!

http://www.evnetics.com/downloads/So...l_1v4_rev2.pdf

Looks like you just need to provide a 12V signal direct from the key switch to turn this controller on as it has a built in contactor, that makes it really easy!

Jesse

[skooler]

I'd recommend installing a new relay that comes on with ignition stage 2 (between acc and start). Anything that you add to the car can then be powered through this relay. The problem with using existing relays is that you do not know how close to the limits they already are.

You can often find something to tap into in the existing fusebox to control the coil on the new relay.

Made my 12 volt systems much simpler.

FWIW. I installed 3 new relays, one for ignition live components such as the controller another for the vacuum switch and another for the motor cooling.

I have a diagram on my home PC, will post it up later on.

Cheers,

Mike

[mmoyer2655]

Thanks for the info on the relays. Never thought of amp load or the option of using the "start" turn of the key.

In other news a made another purchase today.

Batteries!

I found a guy on craigslist selling is Solar Power system. He had 26 Trojan T-105's for sale for $65 a piece. I offered $1200 for all of them and he took it.

They are 2 years old, and were just tested in late June to be 100% operational. (One was bad, but replaced under warranty.)

So, now I've got to figure out how to fit 24 t105s in the Celica. Initial measurements seem very tight. Max in the trunk looks about 17, leaving 7 to place elsewhere on the car.

[Ziggythewiz]

There's always the passenger seat!

24 batts is a lot to stuff in a car.

[mmoyer2655]

Originally Posted by Ziggythewiz

There's always the passenger seat!

24 batts is a lot to stuff in a car.

Yea, I'm thinking worst case scenario, I'll fold down the back seat. But I think I should be able to find room in the hood and possibly build a box where the gas tank used to be.

I also have the option of going to a 120V system and losing 4 batteries.

[Jesse67]

You may be able to find space for them but I think with a celica the problem will be weight. What is the GVWR of your car? 62lbs each for a T105 x 24 is 1488lbs! Also, you can take up the back seat with batteries but they should be in a sealed box to avoid any issues with gas venting in the cab and spilled acid in case of a rollover. They also need a sturdy frame and clamping system to keep them in place. If you have to take up the back seat I would take the seat right out and try to keep your batteries as low as possible in the car.

It can be done, but try to stay below your GVWR and make sure those batteries are secure if you have any in the cab space. If you have access to a scale where you can weight your car and then weigh all the ICE stuff you strip out of it you'll know how much extra GVWR room you have for batteries, motor, etc.

Here's some inspiration although you may have seen these already,

http://www.evalbum.com/613
http://www.evalbum.com/3974/
http://www.evalbum.com/4093
http://www.evalbum.com/2400

Looks like a popular conversion! Most seem to have 8V or 12V batteries though.

Good luck!

[mmoyer2655]

Yea, I'm going to figure out the battery placement Friday. Then I can order my charger.

I emailed those guys on EvAlbum and got two responses. Hopefully I can get some pictures and ideas from them.