• temperature from -100° to +100°C (-212°F to +212°F) The Optica also measures and displays gas pressure using a GE Sensing PT-30A or PT-300A pressure sensor, or a user- supplied 4–20 mA or 0–5 VDC pressure sensor. Note: If the pressure is known to be constant, a fixed pressure can be programmed, eliminating the need for a pressure sensor.
See Chapter 2, Installation, for details on how to mount the Optica. 1.2.1 Front Panel The Optica’s front panel is shown in Figure 1 below. The panel includes: a display, an alphanumeric keypad for data entry, ENTER and TAB keys, and four softkeys to the right of the display screen.
The Optica can be configured with a chilled-mirror dew point sensor. The specific sensor is chosen according to the expected dew point range and the environment in which the dew point is to be determined. In addition, the Optica can be configured with a temperature and/or pressure sensor.
1.5.1 Hygrometer Function Figure 2 on page 5 illustrates how GE Measurement & Control hygrometers detect and measure dew point. The condensate mirror is illuminated with a solid state, infrared emitter (IR). A photodetector monitors the IR light reflected from the mirror.
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Chapter 1. Features and Capabilities 1.5.2 Hygrometer Calibration The Optica unit can be sent to the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland for certification or to any National Standards lab for calibration against their primary humidity standards. A calibrated instrument can then be used as a transfer standard in local laboratories to calibrate lower echelon instruments.
The GE optical condensation sensors cover a wide range of applications limited only by the heat pumping capabilities of the thermoelectrically-cooled mirror.
Automatic Contaminant Error Reduction) that is very effective in reducing the Raoult Effect error associated with soluble contaminants, particularly for near-ambient dew points. The Optica is equipped with the PACER cycle as well as AUTO balance as found on earlier models. The user can choose which self-cleaning and balancing routine to run depending on the severity of contamination.
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Chapter 1. Features and Capabilities [no content intended for this page] Optica™ Operator’s Manual...
2.2 Benchtop Installation 2.2.1 Mounting the Benchtop The Optica benchtop dimensions are shown in Figure 5 below. Two feet on the bottom of the case can be unfolded to raise up the front for easier viewing, if desired. Figure 5: Optica Benchtop Dimensions...
There is an optional kit for mounting the benchtop unit in a standard 19-inch rack (see Figure 6 below, Figure 7 on page 11, and Figure 8 on page 12). The two brackets are attached to the front panel using four No. 8 screws. The Optica is mounted to the brackets using the eight mounting holes located just in front of and behind the unit’s feet.