ThermoFisher Scientific 146iQ, Instruction Manual

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System Description
Peripherals Support System
Thermo Scientific 146iQ Instruction Manual 8-7
The peripheral support system operates those additional devices that are
needed, but do not require special feedback control or processing. These
components are connected to a Peripherals Support Board (PSB).
The chassis fan provides air cooling of the active electronic components.
The Step POL board(s) provide high/low outputs for continuous operation
or on/off states. The Step POL board contains the basic circuitry to provide
a programmable load to passive devices, either continuously, or on user or
automated command. In the iQ Series instruments, the pump, solenoids,
etc., are controlled off of the Step POL board from commands generated
via the PSB.
Internal vacuum pump for generating air/sample through the instrument
Solenoid valves for switching gas standards, zero air, and other optional
components.
The sample and reference gas flows to the photometer and/or the flow to
the ozonator are regulated by the use of flow restricting capillaries on each
path and are monitored by absolute and/or differential pressure sensors on
the flow pressure DMC. Two absolute pressure sensors are utilized to
measure pressure upstream (bench) and downstream (pump) of the flow
restricting capillary providing sample flow to the pump. The pressure
differential between these two sensors determines the sample flow through
the photometer. A single differential pressure sensor across the ozonator
flow restricting capillary determines the flow through the ozonator.
Like the hardware, the firmware is modular and located within
microprocessors distributed throughout the instrument. In the 146iQ,
microprocessors containing firmware are located as follows:
●
Photometer DMC
●
Ozonator DMC
●
Permeation Oven
●
Flow/Pressure DMC
Peripherals
Support System
Fan
Step POL Board
Sample Pump
Solenoid Valve
Panel
Flow/Pressure
DMC
Firmware