Xylem CR500 CIRCULAR CHART RECORDERS - Manual (Page 25)

Global Water
800-876-1172
• globalw.com
- 25 -
Probe Offset Adjust - Ink Style (Pen Offset)
This recorder has been accurately calibrated at the factory. Before making any
adjustments, this instrument should be in service for 24 hours. Thereafter, if any
adjustment is required, perform the following procedure.
1. Place a Certified Test Thermometer(s) alongside the recorder's sensor probe(s) in
a monitored controlled condition.
2. Once the temperature has leveled out, compare the position of the pen on the
recorder to the test thermometer's reading. Also compare the Certified Test
Thermometer s reading to the second pen of the recorder.
3. If an adjustment is required, for a single pen unit, depress and hold either the
LEFT (1) or RIGHT (2) arrow key. The pen will begin to move after
approximately ten (10) seconds. Using the LEFT arrow (1) or RIGHT (2) arrow
keys, position the pen on the chart to correspond to the temperature of the
Certified Thermometer. Once the corrected value is obtained no further
keystrokes are required.
4. For two (2) pen ink recorders, you must first select the pen that you wish to
calibrate. This is done by pressing the LEFT (1) arrow key to select the Red pen
or the RIGHT (2) arrow key to select the Blue pen. The appropriate arrow key
must be held down for approximately five (5) seconds, after which the green
LED will go out. Release the key. The green LED will begin to flash. Adjust the
pen to the desired value. This is done using the LEFT (1) or RIGHT (2) arrow
keys. Once the corrected value is obtained, wait. The green LED will come on
steady (approximately 10 seconds). Unit will then resume normal print operation.
The remaining pen can now be selected and adjusted, if necessary, using
instructions above.
NOTE: If unit has optional display, OFFSET value will be shown on LED.
Figure 4.2 Keypad Layout