New Product: Myers-Vacuum GT-340A & GT-345B Thermistor Gauges

Myers-Vacuum Models GT-340A & GT-345B Thermistor Gauges For Sale.

The 340 is an electrically powered gauge for use in harsh environments. The rugged electronics are designed for longevity and occasional accidental misuse. Two analog scales allow the user to take vacuum measurements from atmosphere to 1x10-3 torr. A separate meter scale for the 1 to 100 millitorr range provides increased readability in this critical area. Meter scales are calibrated in dry air pressure units; calibration curves for other gases are supplied.

Features

More Info on the
GT-340A & GT-345B Thermistor Gauges from Myers-Vacuum

Principle of Operation
A single element is employed in a bridge-type detector driven from a constant regulated voltage source. The inverse resistive characteristics of the sensor unbalances the bridge as pressure changes occur, thereby causing a current change. A microammeter scaled in pressure units measures this current.

Leak Detection
Gauge has Leak Detect Mode. Front panel switch allows adjustment of the gauge sensitivity to aid vacuum leak detection.

Recorder Connection
Connections on the rear panel of the gauge cabinet provide a pressure-responsive output independent of the selector switch. A 10-, 50-, or 100-millivolt high-impedance recorder with suitable attenuating network can be connected here to cover the entire pressure range of the gauge at either sensing station.

Modular Construction
The Type GT-340A thermistor gauge and the GT-005A controller are each mounted in quarter-rack modular cabinets. The GT-345B controlling gauge combines these two modules in a single half-rack cabinet. Two GT-340A two-station gauges can be mounted side-by-side for applications requiring four-station operation, with the added advantages of two read-out meters and redundant circuitry.

Automatic Control of External Circuits (GT-345B)
Relay control unit available. This can either be built with the original gauge, or as an accessory (GT-005A). The trip points of the control are independent of the setting of the selector switch. Normally open or normally closed relay contacts rated at 3-amps, 115/230 volts are available for connecting external loads such as safety circuits for tuning off pressure-sensitive components or automatic circuitry for operating vacuum valves at preset pressures. By utilizing the separate adjustment provided, the pull-in and drop-out point of the relay contacts can be set so control is established at any two pressures within the operating range of the gauge. Indication lights on the front panel show position of relay contacts.

Ordering information for the components mentioned on this page is listed below.