Teledyne 7500 - Infrared gas analyzer - operating manual - Manual (Page 72)

72 Model 7500 Instruction Manual
Teledyne Analytical Instruments
CS: measured concentration of sample gas
Os : Measured O2 concentration
On: Standard O2 concentration (value changeable by
setting)
*The upper limit value of the fractional part in this
calculation is 4. The result of calculation is indicated and
output in an analog output signal.
Average value after O2 correction and O2 average
value calculation:
The result of O2 correction or instantaneous O2 value
can be output as an average value in the determined
period of time. Used for averaging is the moving average
method in which sampling is carried out at intervals of 30
seconds.
(Output is updated every 30 seconds. It is the average
value in the determined period of time just before the
latest updating.) Averaging time is settable within 1 to 59
minutes (in increments of 1 minute) or 1 to 4 hours (in
increments of 1 hour).
Average value resetting:
The above-mentioned output of average value is started
from the initial state by applying a non-voltage rectangular
wave to the average value resetting input terminals
(opened after short-circuiting for 1.5 seconds or longer).
Output is reset by short-circuiting and restarted by
opening.
CO concentration peak count alarm:
(added only for CO/O2 measurement) Alarm output turns
on according to the preset concentration and count.
Whenever the instantaneous value of CO exceeds the
preset concentration value, count increments. If the count
exceeds the preset value in one hour, the alarm contacts
close.
Communication function:
RS-232C (9pins D-sub)
Half-duplex bit serial
Start-stop synchronization
ModbusTM protocol
Contents: Read/Write parameters; Read measurement
concentration and instrument status.
Remark : When connecting via RS-485 interface, an RS-
232C / RS-485 converter should be used.
(4) Applicable standards
Product safety: EN61010-1 :2001
EMC: EN61326-1 :1997, A1 :1998, A2 :2001
(5) Performance
Repeatability: ±0.5% of full scale
Linearity: ±1% of full scale
Zero drift: ±2% of full scale/week
Span drift: ±2% of full scale/week
Response time: (for 90% FS response, including
replacement time of sample gas)
1 or 2 component measurement: Within 15 seconds
3 or 4 component measurement : Within 30 seconds
Interference from other gases:
Interference
component
CO2
ana-
lyzer
CO
analyzer
CH4
ana-
lyzer
SO2
ana-
lyzer
O2
ana-
lyzer
CO 1000
ppm
≤1%
FS
≤1%
FS
≤1%
FS
CO2 15% ≤1% FS (for
200 ppm
analyzer,
≤2.5% FS)
≤1%
FS
≤1%
FS
≤2%
FS
H2O satura-
tion at 20°C
≤1%
FS
≤1% FS (for
200 ppm
analyzer,
≤2.5% FS)
≤1%
FS
H2O satura-
tion at 2°C
≤2.5% FS
(for 200
ppm ana-
lyzer)
≤5%
FS
(6) Standard Requirements for Sample Gas
Flow rate: 1L / min ±0.5L / min
Temperature: 0 to 50°C
Pressure: 10 kPa or less (Gas outlet side should
be open to the atmospheric air.)
Dust: 100 µg/Nm3 in particle size of 0.3 µm or less
Mist: Unallowable
Moisture: Below a level where saturation occurs
at room temperature (condensation unallowable). Below
a level to cause saturation at 2°C for CO measurement
with 0 to 200 ppm range and SO2 measurement.
Corrosive component: HCl 1 ppm or less
Standard gas for calibration:
Zero gas; Dry N2
Span gas; Each sample gas having concentration 90
to 100% of its measuring range (recommended). Gas
beyond concentration 100% is unusable.
In case a zirconia O2 analyzer is installed externally
and calibration is carried out on the same calibration gas
line:
Zero gas; Dry air or atmospheric air
Span gas; For other than O2 measurement, each
sample gas having concentration 90 to 100% of its
measuring range. For O2 measurement, O2 gas of 1 to 2
vol%.
(7) Installation conditions
Use this instrument indoors.
(Select a place where the equipment does not receive
direct sunshine, draft/rain or radiation from hot
substances. If such a place cannot be found, a roof or
cover should be prepared for protection. )
A vibration-free place.
A place which is clean around the analyzer.