Electronic Corrosion Protection

[Bernie]

Speaking as a ham radio operator all I can say is... snake oil.

The theory is very suspect because RF simply does not travel that way on your average vehicle. Yes, it will travel like that on an isolated piece of steel, but as soon as it hits a cross member, a weld, or a through bolt the whole RF pattern is going to change.

And, I can't believe they're actually marketing this towards emergency vehicles, given the huge amount of problems stray RF can cause in medical equipment and communications equipment.

Well from years of experience with seeing the systems work on ships. I can say that in theory they do work and we have as much radio and communications stuff as a small city on a ship. With not the first bit of interference from any of the systems. Here's a quote from Wilson Walton's website, explaining the principle of the systems that we use. This defender sounds like it operates the same way.

Impressed Current Cathodic Protection

The basic cause of corrosion is the instability of metals in their refined forms. All metals tend to revert back to their natural states, especially when exposed to an environment such as saltwater. Thus iron, as the dominant element in steel, tends to oxidize or corrode to form rust.
The corrosion of metals in seawater is electrochemical in nature. This means that a flow of electricity (electrons) occurs between different areas on the same metal surface, through a solution capable of conducting an electric current (electrolyte). This electrochemical action causes deterioration or wastage of the metal.
Electrochemical reactions are precise and measurable in volts, making it possible to calculate the amount of metal which will be lost to corrosion. For this same reason, it is possible to exercise control.
The purpose of cathodic protection is to prevent corrosion on the exterior underwater areas of steel-hulled vessels. An Impressed Current Cathodic Protection (ICCP) system, such as Aquamatic III, is a sophisticated method of corrosion control that supplements the coating, which is generally considered the primary means of hull protection.
An ICCP system is known for its versatility, effectiveness, controllability and long-term service. The system includes seven major components:

1. Reference electrodes
2. Controller
3. Power supply
4. Anodes
5. Tailshaft & propeller grounding assembly
6. Rudder stock grounding assembly
7. Datalogger

These units are electrically connected together to form a closed loop with the ship hull for maintaining a selected constant level of protection. The combination results in a sophisticated electrical system which performs the following functions:
1) The reference electrode measures a voltage difference between itself and the hull, which is directly related to the amount of protection received by the hull.
2) The controller compares the voltage difference produced by the reference electrode with a preset internal voltage. The output is then automatically adjusted to maintain the electrode voltage equal to the preset voltage.
3) The power supply, in response to the signal from the controller, regulates the amount of shipboard alternating current fed into the rectifier, and converts the regulated AC to direct current which is impressed on the anode.
4) The anode is mounted on the ship's hull in an insulated reinforced resin holder. The DC from the power supply is fed through the anode to the hull, thus completing the electrolytic circuit.
5) The tailshaft & propeller grounding assembly feeds protective current to the intermediate tailshaft and propeller, in addition to safeguarding against premature main engine bearing and journal failure.
6) The rudder stock grounding assembly allows protection to be provided to the rudder.
7) The datalogger is an IP Logger intelligent system which twice-daily records and uploads ICCP system readings to the ship's computer for e-mail transmission to WWI and/or owner's office.
The demand for current is governed by the wetted surface area of the ship and propeller, the condition of the hull coating, temperature, pH and conductivity of the seawater, and the speed and draft of the ship.
Basically, as the current is increased, the hull corrosion rate decreases substantially until the protective polarization level is reached. Increasing the current beyond this point offers no additional benefit.

There's a big difference between RF current (which the Defender claims to use) and electrical current (which shipboard systems use). The two are not even remotely the same J-Rod.

 

[ScottyBoy]

Rust is pretty much a non-issue here in Louisiana. Unless its a 20+ year old vehicle that was never garage kept. But still, we don't have any issues with the undercarriage or suspension rusting. Hell, when my old Cutlass was flooded in Katrina it began to rust and I've seen worse pictures of rust on some winter beaters up north. I sold that car because it had so much rust, and I still see it being driven around town all the time. It still has the same cracked windshield and the University of New Orleans parking decal on the rear window.

 

[Bigredmariner]

[YT]5W7o4WVduCI[/YT]

There's a big difference between RF current (which the Defender claims to use) and electrical current (which shipboard systems use). The two are not even remotely the same J-Rod.

Sorry Bernie, I didn't read the literature claims of the Defender, I was just basing my statement off of the video advertisement. I didn't see any reference to RF in the video only impressed current which I am familiar with.

 

[Bernie]

There's a big difference between RF current (which the Defender claims to use) and electrical current (which shipboard systems use). The two are not even remotely the same J-Rod.

Sorry Bernie, I didn't read the literature claims of the Defender, I was just basing my statement off of the video advertisement. I didn't see any reference to RF in the video only impressed current which I am familiar with.

Yeah, the RF part is what caught my eye in their animated video on the site. I took one look at that and went, "WTF?" because RF does not travel that way, not to mention the fact that even if it did the levels needed to do what they're claiming would be well beyond the maximum permissible limits for RF exposure.

 

[daddy]

Help the non-radio nerd understand where exactly they said RF, please.

 

[ScottyBoy]

Go kill your selfs. All of you.

 

[nubuilder]

Go kill your selfs. All of you.

You got kill yourself!

 

[ScottyBoy]

Go kill your selfs. All of you.

You got kill yourself!

Don't worry, I am. With all the drugs I take my liver wont last forever.

 

[Bernie]

Help the non-radio nerd understand where exactly they said RF, please.

Go to their site and watch the animated "How it works" video they have.

Here's the link: http://defender-plus.com/defender_english/html/howitworks.html

 

[daddy]

Help the non-radio nerd understand where exactly they said RF, please.

Go to their site and watch the animated "How it works" video they have.

Here's the link: http://defender-plus.com/defender_english/html/howitworks.html

Ahhhhh, I see now. I was looking for it in the video, not there. Thanks, Bernie!