Powerwise charger diagnosis

[yurtle]

Originally Posted by kobx

Update: opened up the plug to take a look at the aux. contact, and immediately saw the problem. Some how the blade terminal had slipped of the beryllium contact, and was barely hanging on. I reconnected it, closed it up, and plugged it into the cart. Voila! Charger comes on no matter how it's jiggled....

Thanks again for all the input/advice

You have a Beryllium contact?

Glad you got it fixed.

[kobx]

Originally Posted by yurtle

You have a Beryllium contact?

Glad you got it fixed.

I'm assuming that's what it is. Usually contacts that require any kind of "spring" force are Beryllium Copper alloy. But my experience is solely in aerospace, so I could be wrong when it comes to golf carts.

[JohnnieB]

Originally Posted by kobx

I'm assuming that's what it is. Usually contacts that require any kind of "spring" force are Beryllium Copper alloy. But my experience is solely in aerospace, so I could be wrong when it comes to golf carts.

What you say about "spring" contacts is true throughout the electronics industry, including golf carts.

[yurtle]

Learned something new. I guess copper wouldn't make sense. Not springy.

[JohnnieB]

Originally Posted by yurtle

Learned something new. I guess copper wouldn't make sense. Not springy.

Another tid-bit to add about Beryllium Copper (BeCu).

The Gold plating on high-end battery contacts is only a few molecules thick on a springy thingy made of BeCU. If the batteries are changed fairly often, the Gold plating wears through, exposing the BeCu to the atmosphere inside the battery compartment.

When Alkaline batteries (Zn/MnO2) are used, they outgas Di-manganese Tri-oxide (or something like that- I don't remember off-hand) which reacts with the BeCU and forms a thin, nearly invisible, resistive layer. This effectively places resistors between the cells, so a battery pack made up of multiple Alkaline cells acts like one whose cells need to be replaced.

I spent a lot of time on the phone with battery manufacturers finding that little tid-bit out.

[kobx]

Originally Posted by JohnnieB

Another tid-bit to add about Beryllium Copper (BeCu).

The Gold plating on high-end battery contacts is only a few molecules thick on a springy thingy made of BeCU. If the batteries are changed fairly often, the Gold plating wears through, exposing the BeCu to the atmosphere inside the battery compartment.

When Alkaline batteries (Zn/MnO2) are used, they outgas Di-manganese Tri-oxide (or something like that- I don't remember off-hand) which reacts with the BeCU and forms a thin, nearly invisible, resistive layer. This effectively places resistors between the cells, so a battery pack made up of multiple Alkaline cells acts like one whose cells need to be replaced.

I spent a lot of time on the phone with battery manufacturers finding that little tid-bit out.

Now you're just showing off....

[JohnnieB]

Originally Posted by kobx

Now you're just showing off....

Guilty as charged.

FWIW: What I summed up in a couple sentences, took nearly four months to discover and involved a medical device manufacturer, the FDA and three disposable battery manufactures, plus a sprinkling of lawyers and accountants.

The guy that finally connected the dots was an old school chemical engineer at the P.R.Mallory Battery company (precursor to Duracell International) that was getting ready to retire.

This was during the era when EPA was forcing battery manufacturers to remove Mercury from their primary (disposable) cells. Prior to the reduction of Mercury in the electrolyte-electrode interface, the increased resistance caused by corrosion on the BeCu contacts didn't cause a noticeable problem.

[cgtech]

Wouldnt be the first time a "sensible solution" drove techs nuts trying to figure out WTH happened!