What is this?

[swanson37]

What is this thing...it has one wire coming out of the back connected to the common on my 1-2-both switch and the other (the yellow and red joined up one) that goes nowhere (that's not to say it didn't go anywhere originally)

Cheers

 

[AndrewB]

Heat sink.

Quite likely the regulator of an electricity generator eg wind turbine or solar panel. That's consistent with it being connected to your main battery switch, so it would charge whichever battery is 'on'.

If so you need to be a bit careful since it may be + earthed when other electrical devices aboard (eg the engine) are generally - earthed. Pull it out if it is no longer connected to anything useful.

 

[tangofour]

Re: Heat sink.

[ QUOTE ]
Quite likely the regulator of an electricity generator eg wind turbine or solar panel. That's consistent with it being connected to your main battery switch, so it would charge whichever battery is 'on'.

If so you need to be a bit careful since it may be + earthed when other electrical devices aboard (eg the engine) are generally - earthed. Pull it out if it is no longer connected to anything useful.

[/ QUOTE ]

Nope its a diode.

The 'common' on your 1/2 switch is actually system positive. The loose end probably went to some sort of charging system, perhaps solar panel or wind genny.

The aluminium heat sink may well be 'live' if the diode has not beeen fitted with an insulating kit. Strip it out but keep it in the spares box it'll cost £15 to replace the bits if you fit a charger.

 

[simonfraser]

Re: Heat sink.

agree, it's a diode

 

[nigelmercier]

Re: Heat sink.

[ QUOTE ]

agree, it's a diode

[/ QUOTE ]
Thirded!

 

[misterg]

Re: Heat sink.

[ QUOTE ]
Quite likely the regulator of an electricity generator eg wind turbine or solar panel.

[/ QUOTE ]

[ QUOTE ]
Nope its a diode.

[/ QUOTE ]

Nope, it's both /forums/images/graemlins/cool.gif

Almost certainly a zener diode used for voltage regulation (that's why it's on a big heat-sink).

The heatsink is [edit]usually[/edit] connected to the cathode of the diode and battery negative. The other wire would be connected to whatever needed regulating *in parallel* with the battery. (i.e. the diode is connected in reverse). Normally no current flows, but if the voltage exceeds the rating of the zener, it starts to pass current, limiting the voltage, and generating heat.

Andy

 

[mikefleetwood]

Re: Heat sink.

Sorry to dissagree with you MisterG, but it is just a diode, left over from some other charging system, as others have said.

A Zener regulator would be connected between ground (-Ve) and supply (+Ve), probably would have to be used in conjunction with a diode too. Not connected like that, so unlikely to be this.

Any other sort of regulator would require three connections - ground/common (-Ve), supply from charger/alternator/etc. (+Ve) and output to battery (+Ve).

So definitely a diode. Almost certainly "live" to battery +Ve on the heatsink, so better disconnected if not needed. But keep it though as fairly expensive to buy again and you might need it in future!

 

[smiala]

Re: Heat sink.

I vote Zenner, as why have the heat sink ?
As above Zenners can be used to regulate, albeit a rough way to do it.

 

[tangofour]

Re: Heat sink.

[ QUOTE ]
I vote Zenner, as why have the heat sink ?
As above Zenners can be used to regulate, albeit a rough way to do it.

[/ QUOTE ]

Because a diode drops about .6 volts across the forward bias. Lets assume a forward current of 20 amps thats 12 watts to dissipate. A good chunk in semiconductor terms.

 

[swanson37]

Re: Heat sink.

Thanks for the advice chaps, I'll take it out and stick it in the spares box. The boat did have a wind generator on it in the past (someone wrote something on the hull about it).

Cheers