| | Introduction | 1 |
| | Specifications |
| Relative Humidity (Storage): 0 to 95% (non- | |
| condensation) | |
| Relative Humidity (Operating): 0 to 90% (non- | |
| condensation) | |
| Irradiation: 3.5 to 1 x 103 Rads @ 60°C integrated over |
| 40 years life. | | |
Mounting | 876-1-55, Rack Chassis | |
Available Options (consult factory) | 876A-100: Readout, for use with digital systems | |
| Outputs: 0 | - 100 mV | |
| 0 | - 50 mV | |
| 0 | - 10 mV | |
0 - 5 V
Figure 1-2 illustrates the typical energy response for the detector, Figure 1-3 illustrates typical linearity for the detector and Figure 1-4 illustrates radiation input versus meter reading.
1.3 Equipment Overview
High-Range Containment Monitor Detector (877-1)
The high-range containment monitor detector is an ion chamber detector that has the appearance of a six-inch diameter domed cylinder about seven inches long. Inside the cylinder are two flange-mounted electrodes consisting of 31 flat, disk-shaped plates, each about four inches in diameter, stacked, and mounted on disk rods. The assembly has the appearance of a large air capacitor. The mounting posts are attached to the mounting flange through insulating spacers, so the flange and housing will be neutral with respect to the charges applied to the electrodes.
The whole assembly is covered by the six-inch diameter housing which contacts only the neutral mounting flange. The mounting flange is pierced by three holes. One hole supports the exhaust tube used for exhausting and back filling the chamber. The other two support two 2-pin connectors, one for each electrode. One pin in each pair is connected to the neutral mounting flange. When the coaxial signal cable is connected to this connector, the cable shield is connected to the neutral pin.
The entire chamber is filled with a mixture of helium and nitrogen at atmospheric pressure and sealed.
For further information refer to Section 4, Functional Description.
Readout Module (876A-1)
The 876A-1 Readout Module is designed to give an indication, on an analog meter, of radiation levels within the containment area. The readout is composed of an analog meter, indicator lights and operating switches. The meter has a range of 1 to 107 R/h and is controlled by an eight position rotary switch. The readout is mounted in the 876-1-55 Rack Chassis located in the control room.
For further information refer to Section 4, Functional Description.
Rack Chassis (876-1-55)
The 876-1-55 Rack Chassis permits mounting of two readout modules or one readout module and one optical isolator in a 19-inch wide RETMA equipment rack. The panel height is 5.21 inches.
For further information refer to applicable drawing located in Appendix C.