The Barton weatherproof Model 289A and the explosion-proof Model 291B are differential pressure indicating switches. The 289A has a NEMA-4 watertight die-cast aluminum case (finished 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 accidental 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.
ITT Barton Model 291B has an explosion-proof case that is certified for Class I, Division 1, Groups B, C & D service. The large cover lens allows maximum readability of the indicating pointer.
Switches and all adjustments are readily accessible when the cover is removed. The built-in switches energize either single or dual alarm circuits when the measured differential pressures exceed predetermined limits. These limits may be either maximum, minimum, or both.
If you need more information about ITT Barton 289A and 291B please contact our sales department vias firstname.lastname@example.org and look at our website: http://ittcontrols.com/brands/itt-barton/