Linear DC Analog Module
Detector: compensated ionization chamber
Measuring range: 10-11…10-3 A (in 8 ranges)
Neutron flux measurement in intermediate and power ranges
High voltage generators: included (positive and negative)
Multiline: analog and digital signals without intelligence.
RS 422 serial I/O
Powered from single power supply
The RNL-03.02. Linear DC Analogue Module is used for the measurement of currents from compensated ionization chambers. It serves for the measurement of the neutron flux in the intermediate and power range. The current from an ionization chamber, with the values of 10-11…10-3 A, is fed to the equipment through a coaxial cable. A linear DC amplifier with 8 switchable ranges converts detector signal into a measurement current of 0/4…20 mA. The range switching is accomplished by automatic or manual manner, depending on the state of AUT/MAN signal. In manual state the range is controlled by RANGE UP or RANGE DOWN binary signals controlled electronic stepping-switch system. The TEST GEN. is controlled from TEST ON input. If this level is high, a 5 mA current is switched to the amplifier.
The positive and negative HV power supplies are built up of encapsulated circuits surrounded by current-loop driven isolated set-value controls and HV-monitoring isolation amplifiers. Both set-value control signals (HV+CNTR and HV-CNTR), and monitoring signals (HV+MON and HV-MON) are connected to RS 422 serial I/O lines.
The module is located in a double-shielded box out of the reactor vessel. It is built in massive brass housing to protect from electro-magnetic interference waves and cross coupling. This unit is installed isolated into additional die-cast aluminum housing. This insulated installation provides an additional protective screen. Maximum 200 m long cable ensures the electrical connection between the analog module and Neutron Flux Data Processor.
The primary supply of power enters the board. Transient protection from the outside world is done by fuse diode. It saves the inputs of a four-member group of isolated DC-DC converters from damages. The unit also contains an isolation amplifier-current loop function to get the primary power monitoring signal (MON POWER S) output.
Main Technical Data