Cartek Isolator

[shmed]

Can the Syvecs S6 be used with the Cartek Battery Isolator XR?

I found something that said:
AN15 = AR3 Test Mode (D5 on EU or D14 on JDM) [KILL/ALS/LAUNCH/CAL]

Is any additional config required to make the ECU kill the engine?

http://www.cartekmotorsport.com/ISOLATO ... 0sheet.pdf

[stevieturbo]

Are you wanting the isolater just to shut the engine down, or shut all car systems down as would normally be the case ?

ie kill the ecu and all other systems...the engine is going to stop anyway.

It would be unusual to hit an electrical kill switch, and leave some electrical systems operative ?

[shmed]

The XR model sends a signal to the ECU indicating that the kill switch has been activated. It then gives a small delay so the ECU can prepare the engine for the electrics to 'die'. I was wondering if the Syvecs could act on this signal to maybe pull some power from the engine before it unexpectedly cuts off.

This unit does not have a power input or power output. Instead it sends a signal which is wired up to either a Power Distribution Module or Motorsport ECU that has an ignition switch signal input. The ECU or Power Distribution Module will then shut down when it see’s this signal - which then kills the engine.

The new Battery Isolator XR also features a 0.5 sec time delay between transmitting the engine kill signal and disconnecting the battery allowing ECUs time to perform a shutdown sequence before electrical power is lost.

[TimH]

I'm not aware of any "kill/shutdown" functionality in the ECU - I have wired this signal to a PDU before now, so you have some control over what power gets removed first although realistically it's a moot point since the kill switch doesn't really cause any different behaviours compared to simply turning the ignition key off on the majority of Syvecs installs.

[shmed]

Fair point. I'm also developing a PDM so I guess I could use the signal from the Cartek to do 'stuff' before the power goes. Not sure what though

[Jackstrath]

if its any help to you , i have that on my car , had it pre syvecs , as the alternators were known to continue to charge and fry things in the process if you used the normal switch type cut off

in the end i wired mine to cut the power to the coil packs first then kill the power , it all happens so fast tho , iv now got my car running on syvecs and it still works fine !

[stevieturbo]

if its any help to you , i have that on my car , had it pre syvecs , as the alternators were known to continue to charge and fry things in the process if you used the normal switch type cut off

in the end i wired mine to cut the power to the coil packs first then kill the power , it all happens so fast tho , iv now got my car running on syvecs and it still works fine !

There are very specific ways they want you to wire things to prevent alternator damage.

I've never quite understood them myself...I feel keeping the alternator hard wired to the battery at all times is the safest for that, although some bodies think not for whatever reasons.

Easy to do if the alternator/battery are close...less easy to do if they are not.

[TimH]

The way to think about it is that if you kill power to the engine, it's still spinning and still generating volts. Where can the current go?

If the battery is totally isolated the current is likely to dump back through the ECU and fry it.

But to be a total kill, to prevent anything in the car being live in a crisis/crash, you do have to disconnect the battery. It's imperative.

An MSA kill switch is simple but clever. When you "kill" it instantly removes power from the coil/coilpacks/ignition system so the engine stops, but also provides a path for the alternator to dump power via a resistor to ground. And, most importantly, has completely isolated the battery from the car.

The correct approach is to wire the battery live and the alternator back to the MSA switch, so the location of the battery is not really relevant. If you hard wire the battery to the alternator, then there will always be volts at the alternator even when you've "killed" the car - not good!!

As an aside, I have rewired 3 track cars recently that haven't had this resistor, or any other wiring to deal with this, so were in danger of frying ECUs. As another aside, S8 seems more prone to catastrophic destruction than an S6 - don't know why!

MSA kill switches disconnect the live, but leave the ground connected.

CarTek isolators actually disconnect the ground not the live. They say - without stating what they do - that alternator "run down" protection is included. I imagine they include some kind of resistive connection to ground so the current has somewhere to flow - who knows!

I've used the CarTek once, as that's what the customer supplied, but prefer the ArmTech hybrid isolator - it also disconnects the ground but has a specific connection for the alternator so it is properly managed and controlled. Never had a problem - but they're not cheap.

[stevieturbo]

If you hard wire the battery to the alternator, then there will always be volts at the alternator even when you've "killed" the car - not good!!

In OEM etc, the battery is always hardwired to the alternator, and ultimately it is the alternator that is providing electrical power for the car.

And in the case of a cutout, if the switch kills everything leaving only the alternator and battery connected....there isnt really anything wrong or dangerous about that and it always leaves a safe path for the alternator..ie the battery, so no matter what the mode of shutdown, the alternator could never be damaged.

[TimH]

It's not a case of the alternator being damaged - it's a case of volts present in a race car that's had a major crash and is spewing fuel everywhere!

A kill switch - rather than road-car ignition switch - is to completely isolate the battery in the case of a crash; not to shut the engine down after a session! I would rather wire a car to save the drivers life than save a £100 alternator. YMMV

And, to be pedantic, most OEM wiring I've seen at least connects the alternator to the battery via a (big!) fuse (link) so there is at least some chance of a disconnect in a crash. That's not usually there in race/track cars.