Teledyne T801 Carbon Monoxide Alarm User Manual


 
Teledyne API T801 NDIR CO2 Analyzer Operation Manual Principles of Operation
209
Finally, the CPU issues commands via a series of relays and switches (also over
the I
2
C bus) located on a separate printed circuit assembly to control the function
of key electromechanical devices such as heaters.
Flow/Pressure Sensor PCA
CO
2
Sensor
Heater
Analog Outputs
Aout 1
Aout 4
Analog Outputs
(D/A)
External Digital I/O
Power Up
Circuit
P
C
1
0
4
B
u
s
PC 104
CPU Card
Disk on
Module
Flash
Chip
Aout 3
Aout 2
TEST CHANNEL OUTPUT
Status
Outputs
1 - 8
Control
Outputs
1 – 6
Optional
Current
Loop
Outputs
CPU
Status
LED
I
2
C Bus
Thermistor Interface
Box
Temperature
Sample Flow
Sensor
A/D
Converter
RELAY PCA
I
2
C
Status
LED
CO
2
Range 2
CO
2
Range 1
MOTHERBOARD
Sample Pressure
Sensor
Sensor Inputs
CO
2
Sensor
Internal
Digital I/O
CO
2
Sensor
Temperature
CO
2
Concentration
COM2
Female
RS232
Male
Ethernet
USB COM
port
ANALOG
IN
(
I
2
C Bus
)
COM1 (RS-232 only)
COM2 (RS-232 or RS-485)
or USB
Touchscreen
Dis
p
la
y
LVDS
transmitter
board
USB
Figure 12-5: T801 Electronic Block Diagram
12.5.2. CENTRAL PROCESSING UNIT (CPU)
The unit’s CPU card is installed on the motherboard located inside the rear panel.
It is a low power (5 VDC, 720mA max), high performance, Vortex 86SX-based
microcomputer running Windows CE. Its operation and assembly conform to the
PC/104 specification.
07274B DCN6418