Circuit Breaker Switch Fuse Normally Closed Thermal

VK3AXI

New member
I am after some advice. I have a battery charger that does not work. The Sylvania Thermal Switch has burnt out. It is similar to the the one in the picture but it is the SB600 or SB700. What could I replace it with.- I know it would be cheaper to buy a new charger but that's not the point.
 

Attachments

BillC

Active member
Hi Peter, My few cents worth, your old unit seems to be encapsulated in a sealed glass housing, so it would be explosion proof in the event of any switching arc in the presence of a gaseous atmosphere, hydrogen gas etc. The ordinary current trips look pretty good easy to obtain too.
 

VK3YNV

Administrator
Staff member
Hi Peter, My few cents worth, your old unit seems to be encapsulated in a sealed glass housing, so it would be explosion proof in the event of any switching arc in the presence of a gaseous atmosphere, hydrogen gas etc. The ordinary current trips look pretty good easy to obtain too.
Good point Bill, over charging batteries in an enclosed space could well lead to hydrogen gas building up.

The other point of difference is that the original glass tube version would automatically reset after the bi-metallic strip cooled down, whereas the circuit breaker type requires manual intervention to reset.

I wonder if a polyswitch might be a better choice?

 

BillC

Active member
Hi Ray, The original glass tube versions look like a really good device. I did see some auto reset automotive types in Jacar this afternoon but the current rating might be too high for Peters' application. It is hard to say which type is best, I might prefer the manual reset. With an overload the automatic reset variety I think might continuously cycle at the Thermal Delay Rate and wear itself out. In the Pre-Digital days we would wire a headlight globe in series with the charger wire. Cheers.
 
Top