Dwyer LCR20 - Manual (Page 16)

LCR20 IOM Page 16 of 20 April, 2003
Chapter 4 Calibration
4-1 Pen Arm Calibration
Pen calibration is a two point calibration. To check and/or adjust the
recording pen(s) calibration to the inner and outer graduations of the
chart,
Perform the following.
1. Remove power to instrument and remove the 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 pens will move off scale, The LED will fl ash rapidly. The Green
LED will then go to steady on.
4. The Blue pen will then move to the 100% ring. Adjust the Blue pen
using the LEFT (1) and RIGHT (2) keys to position pen on the 100%
ring, if necessary, Then Wait.
5. The red pen will then move to the 100% ring. Adjust pen using the
LEFT (1) and RIGHT (2) keys to position pen on the 100% ring, if
necessary, Then Wait.
6. The Red pen will then move to the 0% ring. Adjust the pen position
using the LEFT (1) and RIGHT (2) keys, if necessary, then wait. The
Red pen will then move full upscale.
7. The Blue pen will then move to the 0% ring. Adjust the pen position
using the LEFT (1) and RIGHT (2) keys, if necessary, then wait. The
Blue pen will then move full upscale.
If unit has alarms enabled pens will now go to current alarm settings
(See Section 3.2), then to the actual recording values.
If no alarms are enabled pen will then go directly to actual recording
values and begin normal operation.
Each time the chart paper or fi ber tip pen cartridge is changed, you
should make sure that each pen stops at the inner and outer most
temperature graduations of the chart paper. Otherwise, this pen offset
can cause the unit to record an incorrect value on the chart.