Forum Discussion
wa8yxm
Nov 05, 2013Explorer III
There are two types of "Thermal" Flashers (Actually 2x2x2 but we won't even mention the other splits)
Standard and Heavy duty
The standard flasher as the current passes to the lamps, it heats a bi-metal strip and eventually it opens the curcuit, Just like a self resetting thermal circuit breaker (Which is exactly what it is)
YOu add more lamps and they short blink BLI---off---BLI---Off instead of BLINK--off.
Then there is the HEAVY DUTY thermal breaker.
On this one when you flip the lever, current flows in a HEATER wire, not through the bi-metal strip which is much, much heavier. When it's hot enough the switch CLOSES shorting the heater and passing current to the lamps.
You double the number of lamps.. NO CHANGE IN BLINK RATE.
Neither of these are short circuit proof. but the HD units can take dang near anything else.. Reverse polarity don't bother them either.
THe other 2 splits
2 or 3 terminal
Loud or Standard click.
Standard and Heavy duty
The standard flasher as the current passes to the lamps, it heats a bi-metal strip and eventually it opens the curcuit, Just like a self resetting thermal circuit breaker (Which is exactly what it is)
YOu add more lamps and they short blink BLI---off---BLI---Off instead of BLINK--off.
Then there is the HEAVY DUTY thermal breaker.
On this one when you flip the lever, current flows in a HEATER wire, not through the bi-metal strip which is much, much heavier. When it's hot enough the switch CLOSES shorting the heater and passing current to the lamps.
You double the number of lamps.. NO CHANGE IN BLINK RATE.
Neither of these are short circuit proof. but the HD units can take dang near anything else.. Reverse polarity don't bother them either.
THe other 2 splits
2 or 3 terminal
Loud or Standard click.
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