Viasensor G200, Руководство по эксплуатации

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OMG200N1.24
G200 Analyzer Range
VIASENSOR Page
36
7.5.1 Zero Calibration
For maximum accuracy it is recommended that the measurement channel is zeroed
using bottled gas (certified 100% N
2
). However, if nitrogen gas is not available the
optional soda lime CO
2
filter kit can be fitted to the gas inlet. This allows the user to
perform a zero using normal air as the soda lime CO
2
filter will absorb virtually all CO
2
from
the sample air. For both these options select 'Key 1-Zero with N
2
' from the user calibration
menu.
If neither of the recommended methods is available the user can select the option to
perform an air calibration. This option assumes that the user has access to fresh air at
around 390ppm. Generally, this can be found outside or in a well ventilated corridor
(typically, an office or lab would have a higher CO
2
concentration).
1) From the ‘Main’ menu select ‘Key 3 – Calibration’ and the following screen is
displayed:
User Calibration
2) Select either;
‘Key 1 - Zero with
N
2
’ (
recommended) or,
‘Key 2 - Zero with Air’ from the menu.
Then, either attach the 100% N
2
or sample pipe to allow access to fresh air.
3) Press the ‘Start’ key. The instrument will now wait (a minimum of 60 seconds) for
the gas reading to stabilize at the correct level. If zeroing with air press the ‘Pump’
key to draw in fresh air. This operation will time out after five minutes if readings
cannot be stabilized.
4) The instrument will then indicate a successful zero has been completed. Press the
soft-key ‘Accept’ to confirm the calibration and store the new user offset.
Alternatively, soft-key ‘Reject’ to exit without change.
?
Note: If the calibration failed then purge and try again or select a different air
source.
?
Note: If using G210 – very high concentrations of CO
2
may take up to 30
minutes to purge completely.
7.5.2 Span Channels
It is recommended that the instrument is spanned to target the desired reading range
(e.g. 5%); ideally this should not be a low level close to zero.
1) If not already preset, enter the correct span target , i.e. certified concentration of
your calibration gas. Press ‘Key 1’ and enter the new value. Then attach the gas and