Michell Instruments XZR200, User Manual

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.