The Model GC-1 Relative Humidity Generator has a 4 cubic foot chamber designed to perform NIST-traceable calibration of several large RH instruments or many small instruments. The GC-1 delivers highly accurate and repeatable calibrations in less time and at lower cost than competitive devices.

The GC-1 is based on the proven divided flow technology made popular in the Model C-1 RH generator, General Eastern's portable RH test chamber. Divided flow in the time domain excels as a reliable method for accurately controlling relative humidity at a fixed temperature.

The user supplies a source of dry gas to the generator and provides distilled water as necessary. The desired RH is selected on the front panel. Relative humidity is automatically controlled by time proportioning a fraction of a constant flow dry air stream through a saturator and into a mixing chamber. The saturated air rejoins the remaining dry air and mixes to the desired RH value before flowing into the test chamber. The large chamber will accommodate numerous RH probes or several humidity recorders for efficient, simultaneous calibration.

The GC-1's continuous digital control, using a built-in General Eastern chilled mirror dew point hygrometer, makes the GC-1 a traceable relative humidity transfer standard with which to calibrate other devices. Therefore, calibrations meeting the requirements of ANSI Z540-1-1994, MIL-STD 45662A, 10CFR-50 and ISO 9001 may be performed.

Included with the GC-1 is the Prostep™ software package which allows the user's computer to automatically control the entire calibration cycle via a standard RS-232 serial data port.