Michell Instruments XZR200, Руководство пользователя

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XZR200 User’s Manual
Michell Instruments 11
INSTALLATION
The new Automatic Calibration value is now stored in memory. This value is retained on
power loss.
If calibration is required with a different gas of known O
2
concentration, and access to
the RS232 menus with a PC is not available in order to change the calibration percentage,
a manual calibration must be performed.
3.6.5 Adjusting the Minimum and Maximum Ranges of the Analog Outputs
(4-20mA and 0 to 10 V DC)
The XZR200 is factory default to output a range of 0-25% O
2
via its two analog outputs.
This range can be expanded to 0 to 100% O
2
as described in Section 2.1. When the unit
is recon fi gured to output 0 to 100% O
2
the user also has the option to fully customize
the output ranges via RS232. This is extremely useful in applications where the O
2
variation is within a narrow band as it allows the analog outputs to be tailored to this
limited range.
1. Ensure the XZR200 is con fi gured for 0 to 100% and RS232 operation. See
Section 2.1 on Con fi guration.
2. Connect the XZR200 via the RS232 interface to the PC.
3. Press
ENTER
then enter your security password. Press
ENTER
to access
the menu screen.
4. In the Con fi guration Menu (menu 2) enter the maximum range screen
(Option 3 - Enter O
2
Max Range).
5. The number entered should be between 1.00 and 100.00 to represent the
maximum output range. The number must also be greater than the saved
minimum range.
6. Press ENTER to save and ESC to return to the Con fi guration Menu.
7. Enter the minimum range screen (Option 4 - Enter O
2
Min Range).
8. The number entered should be between 0.00 and 99.00 to represent the
minimum output range. The number must also be less than the saved
maximum range.
9. Press
ENTER
to save.
The new ranges are now stored in memory and are retained on power loss.
An example of changing the min and max output ranges would be in a normal air
atmosphere where the O
2
range is between 20 to 21%. The user could set the minimum
output range to 19% and the maximum output range to 22% and the outputs would
vary linearly in between. The min and max ranges lock out the outputs at the set limits
- so 19% O
2
or lower would set the analog outputs to 0 V DC / 4mA and 22% O
2
or
higher would set the analog outputs to 10 V DC / 20mA.
NOTE: The min and max range adjustment does not apply to the RS232 output
and is overruled if the unit is reconfi gured for 0 to 25% operation.