Teledyne Tablet Accessory T803 Manual De Usuario
Teledyne API T803 CO2/O2 Analyzer Operation Manual
Principles of Operation
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current temperature of the chamber housing to the CPU as part of the bench
heater control loop. Another thermistor, attached to the motherboard, measures
the analyzer’s inside temperature (box temperature). This information is stored
by the CPU and can be viewed by the user for troubleshooting purposes via the
front panel display (See Section 11.1.2).
heater control loop. Another thermistor, attached to the motherboard, measures
the analyzer’s inside temperature (box temperature). This information is stored
by the CPU and can be viewed by the user for troubleshooting purposes via the
front panel display (See Section 11.1.2).
12.6.5.4. ANALOG OUTPUTS
The analyzer comes equipped with four analog outputs: A1, A2, A3 and A4.
The type of data and electronic performance of these outputs are configurable by
the user. (see Section 5.10). All four analog outputs are connected back to the
A/D converter through a Loop-back circuit. This permits the voltage outputs to
be calibrated by the CPU without need for any additional tools or fixtures.
The type of data and electronic performance of these outputs are configurable by
the user. (see Section 5.10). All four analog outputs are connected back to the
A/D converter through a Loop-back circuit. This permits the voltage outputs to
be calibrated by the CPU without need for any additional tools or fixtures.
12.6.5.5. EXTERNAL DIGITAL I/O
This External Digital I/O performs status outputs and control inputs.
STATUS OUTPUTS
Logic-Level voltages are output through an optically isolated 8-pin connector
located on the rear panel of the analyzer. These outputs convey good/bad and
on/off information about certain analyzer conditions. They can be used to
interface with certain types of programmable devices (See Section 3.3.1.4).
located on the rear panel of the analyzer. These outputs convey good/bad and
on/off information about certain analyzer conditions. They can be used to
interface with certain types of programmable devices (See Section 3.3.1.4).
CONTROL INPUTS
By applying +5VDC power supplied from an external source such as a PLC or
Data logger (See Section 3.3.1.6), Zero and Span calibrations can be initiated by
contact closures on the rear panel.
Data logger (See Section 3.3.1.6), Zero and Span calibrations can be initiated by
contact closures on the rear panel.
12.6.6. I
2
C DATA BUS
An I
2
C data bus is used to communicate data and commands between the CPU
and the touchscreen interface and the relay board. I
2
C is a two-wire, clocked,
digital serial I/O bus that is used widely in commercial and consumer electronic
systems. A transceiver on the motherboard converts data and control signals
from the PC-104 bus to I
systems. A transceiver on the motherboard converts data and control signals
from the PC-104 bus to I
2
C. The data is then fed to the keyboard/display
interface and finally onto the relay board.
Interface circuits on the keyboard/display interface and relay boards convert the
I
I
2
C data to parallel inputs and outputs. An additional, interrupt line from the
keyboard to the motherboard allows the CPU to recognize and service key
presses on the keyboard.
presses on the keyboard.
POWER UP CIRCUIT
This circuit monitors the +5V power supply during start-up and sets the Analog
outputs, external digital I/O ports, and I
outputs, external digital I/O ports, and I
2
C circuitry to specific values until the
CPU boots and the instrument software can establish control.
07276B DCN6418