Overview / Design Principle:
This unit incorporates element failure protection. It operates in conjunction with a primary temperature controller to provide positive safety shutdown of industrial heating appliances. If features fully tamperproof trip-free switch, reset button and signal light on front cover. It has both UL and FM listing. Agency recognition is void if instrument is modified from factory standard.
Operation:
The high limit switch is manually reset to reactuate the equipment after shutdown. It can be reset only after temperature has returned below the high-limit setting. The switch is of a trip-free design, i.e. it will not function in the event the reset button is tied or welded down, providing protection from tampering.
Designed primarily for user applications where high temperature limitations can be specified in advance of ordering , the OHL63X is always factory preset to customer requirements and the setting adjustment is factory sealed to prevent unauthorized changing. Note: The element must be purchased with instrument to have switch set correctly. Preset limit temperature is stamped on the rating plate affixed to the side of the control case.
The element failure switch, connected in series with the high limit switch, is factory set are a point below normal ambient, at 50°F, unless otherwise specified. This switch will prevetn appliance start-up if ambient temperature is lower than switch setting or if the instrument’s thermal element has lost some of its fill.
A cover-mounted amber signal light remains energized during normal operation, while the light is de-energized the instant the high limit switch is activated. The instrument also is equipped with capstan cover screws through which a wire may be threaded and secured with a lead seal.
Printable Literature
Contact Us