Designed to test piston-actuated gauges, inflater assemblies, and inflater assembly gauge elements in two basic ranges, 10 to 150psig and 50 to 606 psig, the Model 3665 is housed in a cabinet for bench-top operation with all controls and indicators mounted on the front panel. The method of calibration is by direct comparison of the test item indication with the higher accuracy reference standard gauges of the calibrator.
The calibrator includes a charging valve with an integral relief valve, a feeder hose, a supply hose, and fittings for adapting inflater assembly gauge elements to the charging valve coupling.
The reference standard gauges are precision, 6-inch diameter gauges with mirrored dials. Each gauge is protected against over- pressurization by gauge savers. As additional protection, the low-range gauge pressure circuit includes a pressure-switch actuated solenoid valve, and the high-range gauge pressure circuit includes a pressure relief valve as an integral part of the charging valve. An internal plenum chamber is mounted in the cabinet. The plenum chamber is an aluminum cylinder with a volume of 172 cubic inches. The chamber simulates the volume of a typical tire, strut, or accumulator.
The calibrator is designed to operate from an external source of dry nitrogen or clean, dry air at a maximum inlet pressure of 3000 psig.