Thermo Scientific 48iQTL, Инструкция по эксплуатации

Страница: 234 / 280

System Description
Common Electronics
8-4 48iQTL Instruction Manual Thermo Scientific
A single PCBA with microprocessor provides active controls for the above
elements, performs preliminary data processing, and generates registers that
interact with the higher level system controls.
The temperature of the measurement case is tightly controlled at 43
°
C
over a wide range of operating temperatures via active PID control of the
following components by the optical bench DMC board.
The rear panel fan, which is part of the common electronics in other iQ
analyzers is repurposed in the 48iQTL to provide tight control over air flow
into the instrument. The rear panel fan is plugged into the optical bench
DMC board which controls the fan speed to help maintain a stable
instrument temperature.
The case heater assembly consists of a cartridge heater, heat sink, and a
constant speed fan, controlled by the optical bench DMC board, in concert
with the rear panel fan, to maintain a constant instrument temperature.
The common electronics contain the core computational and power
routing hardware for the 48iQTL, and is replicated throughout other iQ
series products (
Figure 8–2 ). It also contains front panel display, the USB
ports, the Ethernet port, and the optional I/O interfaces (RS-485, analog,
and digital).
Figure 8–3 shows the PCBA interconnect structure for the 48iQTL,
including options. The modular design of the instrument is conveyed in
the architecture. Brief descriptions of the specific PCBAs follow.
Optical Bench DMC
Board
Instrument
Temperature Control
Fan (rear panel)
Case Heater Assembly
Common
Electronics