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Model 288A Differential Pressure Indicating Switch
Section 1
Section 1—Introduction
General
The Barton* weatherproof Model 288A is a diff erential pressure indicating
switch. The Model 288A has a NEMA-4 watertight die-cast aluminum case
(fi nished with a weather-resistant black epoxy resin paint). The cover lens is
secured in the bezel with an elastomer ring to reduce the possibility of acci-
dental breakage. This ring also acts as a seal between the bezel and the case to
ensure a moisture, fume and dust-free atmosphere for the indicator and switch
mechanism. The large cover lens allows maximum readability of the indicat-
ing pointer.
Switches and all adjustments are readily accessible when the cover is re-
moved.
The built-in switches energize either single or dual alarm circuits when the
measured diff erential pressures exceed predetermined limits. These limits
may be either maximum, minimum, or both.
Main Components
Switch
Arm
Adjust
Switch
Adjust
Adjust
Figure 1.1—Switch components
Summary of Contents for 288A
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