Electromechanical Temperature Controls
Fenwal controls manufactures mechanical temperature control devices. The switches are bi-metal switches that use expansion and contraction to cause the switching. This type of mechanism can be extremely accurate but lacks in displaying the temperature. In todays computerized/automated world this type of control tends to be used for over temperature control or alarm as opposed to the process control point.
The FENWAL THERMOSWITCH was invented in the 1930's to control fish tanks, irons and other simple applications, but it was soon realied that they could be used for industrial, commercial and process applications. They're durability, reliability and accuracy are the strong points for THERMOSWITCHES.
THERMOSWITCH® Temperature Controllers are tubular devices featuring an outer shell made of high-expanding metal and internal struts made of low-expanding metal, with a pair of electrical contacts between them.
When the temperature of the media being measured changes, a corresponding change in the spacing of the contacts provides instant on/of
f control with a small differential, resulting in +1°F precision, depending upon the application.
Series 17000, 18000
PROBE TYPE, SPDT
Series Features:
Fast Response - outer shell is the active sensing member
Precise Control - substantially reduces overshoot & undershoot
Extreme Sensitivity - slow make and break contacts, resolution 0.1°F (0.05°C)
Vibration Resistance - best possible control under difficult physical conditions
Cost-effective, Compact, Simple-In-Operation
Numerous Mounting Configurations
Specifications:
Overlapping ranges from -100°F to 600°F (-73° to 316°C)
1200 Watt resistive load at 120/240 VAC
5/8" diameter THERMOSWITCH® models available
Agency Approvals:
UL and CSA
Applications:
Food service equipment
Packaging equipment
Laminating presses
Agricultural equipment
Fenwal's snap action liquid filled THERMOSWITCH® controllers, the expandable liquid surrounding the bellows is in direct contact with the temperature sensing outer shell providing a fast response for accurate temperature sensing. The 20000 series switches are no longer available. Sords Electric has a few left, email us with a part number.
Series 20000, 21000, 22000
PROBE TYPE, SPST
Series Features:
Individually field adjustable micro-switches
One or two micro-switches
Specifications:
Overlapping ranges from 0° to 300°F (-18° to 148°C)
Ratings to 15 A at 120/250 VAC
Factory preset temperatures available
NEMA 4 enclosure available
Agency Approvals:
UL, CSA
Applications:
Food service equipment
Medical vaporizers
Commercial dishwashers
Based on the differential expansion of metals principle, an increase in temperature causes the stainless steel outer case of the Surface Mounting THERMOSWITCH® controller to expand at a greater rate than the internal bridge assembly.
Because the case is in direct contact with the heated surface, a temperature change is sensed almost instantaneously.
Series 30000
SURFACE MOUNT TYPE, SPST
Series Features:
Fully adjustable
Narrow temperature differential
Compact size
Economical
Factory preset temperatures
NEMA 4 enclosure
Specifications:
Overlapping ranges from 50° to 600°F (10° to 315°C)
1200 Watt resistive load at 120/240 VAC
Minimum contact rating of 100,000 cycle
Options:
Cross mounting bracket
Slotted and extended adjusting screw lengths
Factory preset temperature
Special range calibration
Agency Approvals:
UL
Applications:
Plastic laminating presses
Food warming trays
Popcorn machines
Domestic appliances
