electronic rust prevention

Hard to tell really. I've had an ERPS on for two years and haven't noticed any new rust problems on my 7 year old Patrol (I live in the wet tropics near the coast - rust/mould capital of australia).

I don't think they prevent rust so much as slow it down very significantly so that it shouldn't be a problem during the average life of a vehicle. BHP did a trial and found a similar system significantly reduced sulphur induced corrosion on their mine equipment.

I bought the ERPS because a local fertilizer company found their truck bodies lasted longer (carting fertilizer) with an ERPS fitted.

Yep,
I've a a counter act unit for about 3 years and wasn't really sure that it made any difference until I was overseas recently and my battery went flat while I was away! When I returned even thought the car had been undercover the surface rust had really taken hold! 3 months earlier there was not a make on her. Kinda heart breaking really!
I believe they are very effective! And will be putting one in my new car ASAP.

Goran,,96 explorer,live on coast ,,on beach regular ,erps since new,,NO RUST,,,simple,it does work,,,,

The problem with anecdotal reports like those above, is that they can't really prove anything. You would need to have the same car in the same conditions one with and and one without. I think all scientific tests so far have shown no difference. Check out Dr Karl. I think he has something on this.

Goran, read Dr Karl's comments carefully, and see my reply to royce above.

I've just had an EPRS system fitted to my 99% clean 8 year old L'cruiser so I can't prove a thing at the moment.
However, over the next few years I'll be on the beach a lot so will report back in 2005 !
I have a Physics background so the technical explanation of what a capacitative system did towards rust prevention was good enough for me.
And no it deosn't have to be underwater to be effective, but the pads do need to be insatlled on painted suraces to achieve the capacitative effect. !
Have faith.

Doug

Goran, check out these links, but keep in mind that ERPS doesn't use the cathodic system that Dr Karl is talking about:

www.erps.com.au/paul_gibson.html

www.abc.net.au/science/k2/homework/s95524.htm

The ERPS and CounterAct systems both use what is called Capacitive Coupling and as Doug said, the pads need to be fitted to an area of metal with a good thickness of paint (the paint acts as the dielectric in the capactive effect). I went for the ERPS coz it is australian made, cheaper than the counteract, and uses less battery power than the counteract.
Whatever you do don't get a "cathodic" system as they don't work prroperly above water, just like Dr Karl says.