DIYbanter - View Single Post - Ping Don Klipstein

Jeff Wisnia

hr(bob) wrote:

On Dec 8, 7:47 pm, (Don Klipstein) wrote:

In communications, Jeff

Wisnia wrote:

Just what is in the "shunt" built into series string decorative lamp
bulbs which takes over when the filament opens?

Is it something like a PTC thermistor which heats up and melts some
powdered metal into a permanent short?

My curious mind wants to know.

As it turns out, I don't really know what those things are made of.

I would guess the whole string needs some sort of fuse - eventually all
of the shorting devices will do so.

- Don Klipstein )

The fuse in the plug is both for the light string itself, and to
protect against too many strings being plugged one after another into
previous strings and overloading the wires in the string closest to
the power source.

I believe you must be writing about parallel strings with 120 volt bulbs
in them. I was asking about series strings, and I don't think you can
plug another string into those, can you?

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.