The 58T line of adjustable temperature controls from Therm-O-Disc is designed for applications requiring accurate calibration tolerances and narrow temperature differential. The bimetal disc design of the 58T provides instantaneous "snap-action" contact operation, which offers excellent reliability under heavy electrical load conditions - 277VAC, 25 amps resistive and 20 amps inductive.

Typical applications include electric baseboard heaters, room air conditioners, commercial dishwasher,portable and built-in electric heaters and attic ventilator fans.

Switch Actions
The 58T cycling contacts are single pole, single throw (SPST). They can be provided to open on temperature rise and close on temperature fall, as required for electric heat applications; or to close on temperature rise and open on temperature fall, as required for ventilator fans or room air conditioners.
The 58T is available with auxiliary mechanically operated contacts to provide either a double pole break in the "off" position for electric heat applications or a "fan on only" feature.

Thermal Characteristics
Calibration - The 58T can be calibrated at any temperature from 30°F (-1°C) to 150°F (65.5°C). Our preferred calibration tolerance is ±3°F (±1.7°C), with a ±2°F (±1.1°C) tolerance available when required.

Differential - The differential is the difference between the nominal open and close temperatures. Preferred differentials are 5°F (3°C), 6°F (3.5°C) or 7°F (4°C) with a ±2°F (±1.1°C) tolerance. A 4°F (±2.8°C) differential is also available with a ±2°F (±1.1°C) tolerance.

Range - The range is the difference between the thermostat operating temperatures measured at extremes of the set positions of the adjusting stem - full clockwise vs. full counterclockwise. Preferred ranges for the 58T are 30°F (17°C), 45°F (25°C), 60°F (33°C) and 90°F (50°C).

The 58T series from Therm-O-Disc is both UL and CSA recognized.​​​​​​​
UL (File E19279) :
277VAC / 25A/ 100,000 Cycles

240VAC / 10A / 30,000 Cycles

480VAC / 10A / 30,000 Cycles

277VAC / 22A / 30,000 Cycles

350VAC / 15.5A / 30,000 Cycles

600VAC / 10A / 30,000 Cycles

240VAC / 22A / 100,000 Cycles

277VAC / 18A / 100,000 Cycles

CSA (File LR010281) :

277VAC / 25A/ 30,000 Cycles

240VAC / 10A / 30,000 Cycles

600VAC / 10A / 30,000 Cycles

Part Numbering:

THERM-O-DISC 58T1S  302735  L110F,

THERM-O-DISC 58T1S  302868  L110F,

THERM-O-DISC 58T1S  302802  L165F,

 THERM-O-DISC 58T1S  L150F,

THERM-O-DISC 58T1D,

THERM-O-DISC 58T2S,

THERM-O-DISC 58T2D,

THERM-O-DISC 58T1VS

THERM-O-DISC 58T1VD,

THERM-O-DISC 58T2VS,

THERM-O-DISC 58T2VD