Xylem CR500 CIRCULAR CHART RECORDERS - Manual (Page 24)

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IV) Calibration - Ink Type Only
Pen Arm Calibration (Zero and Span)
Pen calibration applies to ink type units only and is a two-point calibration. Since
Thermal stylus units print their own outer/inner ring, calibration is not necessary. To
check and/or adjust the recording pen(s) calibration to the inner and outer graduations of
the chart on ink type units, perform the following.
1. Remove power to instrument. If unit has battery option, also remove battery.
2. With all power removed, press and hold the CHANGE CHART key (3). While
holding the CHANGE CHART key (3), re-apply power. Release key upon
applying power, either AC or battery which ever is convenient.
3. The pen(s) will move off scale, LED will flash rapidly. Green LED will then go
to on steady. If 1 pen ink unit go to step 5 next.
4. The blue pen will then move to 100% ring. Adjust blue pen, if necessary, using
LEFT (1) and RIGHT (2) keys to position pen on 100% ring, then wait.
5. Red pen will then move to 100% ring. Adjust this pen, if necessary, to 100%
ring, using LEFT (1) and RIGHT (2) keys, then wait.
6. Red pen will then move to 0% ring. Adjust pen using LEFT (1) and RIGHT (2)
keys, then wait. Pen will then move full upscale. If 1 pen unit go to step 8.
7. Blue pen will move to 0% ring. Adjust pen to 0%, using LEFT (1) and RIGHT
(2) keys, then wait. Blue pen will now travel full upscale.
8. Pen(s) calibration is now complete.
Pen(s) will then go directly to actual recording values.
Each time the chart paper or fiber tip pen cartridge is changed, you should make sure
that each pen stops at the outer most temperature graduation of the chart paper. If ink
pens do not accurately stop at outer graduation recording error can occur and recorder s
calibration should be reviewed.
Figure 4.1 Keypad