Thermo Scientific DCT6088, User Manual

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Primary Displays & Menus
The Calibration Menu
Use this method infrequently. Manual zero set applies a constant offset
entered by the user to all readings. For example, if the flow reads 250
gal/min and a 10 gal/min offset is applied, the new reading becomes 240
gal/min. To zero the instrument using the manual zero set method, follow
these steps.
Manual Zero Set
1. Ensure that the minimum flow range setting in Min Flow Range setup
menu (32) is the negative equivalent of the maximum flow rate setting
in the Max Flow Range setup menu (31).
2. Enter ‘0.00’ as the manual zero setting in the Zero Set menu (51), then
access the Flow/Net Totalizer primary display (00).
3. Minimize flow in the pipe.
4. Set the damping so that the flowmeter reads a steady flow.
5. Allow the flowmeter to settle for 10 minutes.
6. Take 10 separate flow readings and average. This average is designated
as P for positive in the formula seen in step 10.
7. Disconnect the transducer wires, and reverse the upstream and
downstream wires. The flowmeter displays a negative flow reading.
8. Allow the meter to settle for 10 minutes.
9. Take another 10 readings and average. This value is designated as N for
negative in the formula instep 10.
10. Determine the manual zero point (Zp) by performing the following
calculation:
 
.
2
N P
Z
p


11. Access the Zero Set menu (51) and select Manual .
12. Enter the zero point. If necessary, you can apply a negative offset by
pr/- (plus/minus key).
Thermo Fisher Scientific DCT6088 User Guide 5-15