T104 is 240Volt heavy-duty timer rated for 40amps.
Open following link to identify timer and correct wiring:http://waterheatertimer.org/How-to-wire-T104-Intermatic-timer.html
1) Since fire occurred at screw terminals, then wiring is best suspect, and not timer.
The timer clock motor consumes 3 watts of power and does not get hot, and is not located near the screw terminals where melting occurred.
The switch connections are mechanical and are also not located near the screw terminals.
2) Turn off power, remove plastic cover, take photo of wiring.
Post photo of wiring on Flickr, and then add a comment with link to photo.
Also include amp rating of circuit breaker, and amp rating of salt system.
3) To confirm cause of timer failure, timer can be sent to Intermatic:
Intermatic would also want to see a photo of wiring.
4) If wiring area is overheated, possible causes can include too much amp draw or loose wiring.
For example, if stranded wire and copper wire are under same terminal plate. Or two different gauge wires are under same terminal plate.
When electricity travels along copper wire, the wire is heated. If terminal is not screwed down tight, or wiring under the screw plate becomes loose from heating-and-cooling of wires, or different types of wire under same plate, then the loose wire begins to arc and cause melting and burning.
Other causes can be undersized wire, nearby lightning strike.
Several factors including loose wire can combine together and cause problem.
5) Fire safety:
The timer is enclosed inside a box to prevent overheating occurrences from causing a fire.
The closed box starved the fire of oxygen, but the heat melted plastic parts.
This is why timer box covers should always be kept closed, and why circuit breaker boxes are covered with heavy steel cover and door, and why each switch and outlet has a cover, and why all covers should be kept screwed down tight. No electrical connection should be open to air.
6) Take a moment and rate answer:
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