Thermo Scientific 146i, Instruction Manual

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System Description
Electronics
Thermo Fisher Scientific Model 146 i Instruction Manual 8-9
Motherboard
The motherboard contains the main processor, power supplies, a
sub-processor and serves as the communication hub for the instrument.
The motherboard receives operator inputs from the front panel mounted
function key panel and/or over I/O connections on the rear panel and sends
commands to the other boards to control the functions of the instrument
and to collect measurement and diagnostic information. The motherboard
outputs instrument status and measurement data to the front-panel
mounted graphics display and to the rear-panel I/O. The motherboard also
contains I/O circuitry and the associated connector to monitor external
digital status lines and to output analog voltages that represent the
measurement data. Connectors located on the motherboard include:
External Connectors External connectors include:
• External Accessory
• RS-232/485 Communications (two connectors)
• Ethernet Communications
• I/O connector with Power Fail Relay, 16 Digital Inputs, and 6 Analog
Voltage Outputs.
Internal Connectors Internal connectors include:
• Function key panel and Display
• Measurement Interface Board Data
• I/O Expansion Board Data
• Digital Output Board
• AC distribution
Measurement Interface
Board
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.
Measurement Interface Board
Connectors
Connectors located on the measurement interface board include: