Keep electronics turned on to avoid corrosion

[vw1961]

I once was invited on a big sailing yacht and noticed that even though the boat hasnt left the dock in months, all the electronics, chartplotters,... were turned on.
The captain explained to me he leaves them on because a wire under current doesnt corrode while a turned off wire would.

I had never before heard about that, is it true and what is the physics behind it?

[stormalong]

That captain is wrong. As a matter of fact a wet wire with current flowing through it will deteriorate faster. Think of an electroplating bath.

[Tomodore]

There may be some advantages such as if the unit is warmer it may be less likely to dampness. However the chances are that Garmin or whoever will stop supporting it or lightning will strike or the boat will be sold long before it crashes due to corrosion. Guys, its always guys, come up with hair brained ideas that always have a grain of truth. I am certainly no exception.

[Chotu]

Originally Posted by vw1961

I once was invited on a big sailing yacht and noticed that even though the boat hasnt left the dock in months, all the electronics, chartplotters,... were turned on.
The captain explained to me he leaves them on because a wire under current doesnt corrode while a turned off wire would.

I had never before heard about that, is it true and what is the physics behind it?

The physics is: warm electronics are above the dew point and stay dry. No condensation on them. Cold electronics may fall below the dew point and get wet, corroding more easily.

However, at the same time, if electronics are already wet, a current will help them corrode more quickly.

[Squanderbucks]

Depends on where the corrosion he is working about is. Power and other connections are definitely under more corrosion if the power is on and the connections are not water tight But having them on an warmed up could reduce moisture from condensation coming in around other seals and settle out on the boards inside.

If a person was really anal I suppose the units should be turned off when not actively boating for longer intervals and turned off when the humidity is at its least ie daytime. So use during the day and turning off at night could be a theoretical issue as warm instrument turned off at night could suck in moist air and condensation. But I think you would go crazy trying to pay attention to all that.
Install properly with tight connections.

[jmschmidt]

No the captain is right. For the same reason (moisture) the electronics on big airplanes do not eve have switches to turn them off. Their circuit breakers must be pulled or all ground power to the airplane must be disconnected to shut them down.

For the same reason I never shut off our TV's, desktop computers, scanners or printers. Most are over ten years old. On the rare occasion one of them has to be opened up we and/or the technicians are amazed at the lack of corrosion and we live on the beach in Hawaii on the windward side of the island.

[MarkSF]

Anything with a screen is ageing any time it is turned on, in the sense of getting dimmer.

For CRTs, half life is about 25,000 hours. About the same for Plasma.

LCD displays have a half life of about 60,000 hours, due to ageing of the backlight LEDs.

If you leave a modern LCD TV (or your nav electronics) on all the time, the brightness will be halved in about 7 years. That's an effect I'd certainly like to avoid, given that half brightness would normally be considered to be the end of useful life.

[Searles]

On big ships all the bridge instruments are. always powered up except for maintenance every 1000hrs or as required same in the engine room ,most big ships also have winding gear to slowly turn the main engine and shaft while in port .its is also common on megga yachts ,so yes it’s true in certain cases .⛵️⚓️

[smac999]

the units themselves maybe since they stay warm and will help keep out water. but definitely not the wire.

[longjonsilver]

Last fall i remember reading on CT about a spray on stuff that prevents corrosion in electronics. It was used by the Canadian Coast Guard among others. Does anybody know what it was?

jon

[rslifkin]

Originally Posted by longjonsilver

Last fall i remember reading on CT about a spray on stuff that prevents corrosion in electronics. It was used by the Canadian Coast Guard among others. Does anybody know what it was?

jon

Probably some kind of conformal coating for the circuit boards. A lot of good marine grade electronics should already be coated inside.