Thermo Scientific 42i Instruction Manual page 237

Measurement
Interface Board
Measurement Interface
Board Connectors
Flow Sensor
Assembly
Pressure Sensor
Assembly
Temperature Control
Thermo Fisher Scientific
The measurement interface board serves as a central connection area for all
measurement electronics in the instrument. It contains power supplies and
interface circuitry for sensors and control devices in the measurement
system. It sends status data to the motherboard and receives control signals
from the motherboard.
Connectors located on the measurement interface board include:
Data communication with the motherboard
●
24V and 120VAC power supply inputs
●
Fans and solenoid outputs
●
Cooler control
●
120VAC outputs for the pump and temperature control board
●
Ozonator
●
Flow and pressure sensors
●
Ambient temperature sensor
●
Temperature control board
●
PMT high voltage supply
●
Measurement input board
●
Permeation oven option
●
The flow sensor assembly consists of a board containing an instrumentation
amplifier and a flow transducer with input and output gas fittings. The
flow transducer output is produced by measuring the pressure difference
across a precision orifice. This unit is used for measuring the flow of sample
gas in the measurement system.
The pressure sensor assembly consists of a board containing an
instrumentation amplifier and a pressure transducer with a gas input
fitting. The pressure transducer output is produced by measuring the
pressure difference between the sample gas pressure and ambient air
pressure.
The temperature control board regulates and sets the temperature of the
reaction chamber and converter.
Board
System Description
Electronics
Model 42i Instruction Manual 8-7