Ametek Universal III 509-7X Series - Page 46

Conguration & Calibration
37
3.14.2 Validation Procedures
A. Drexelbrook Laptop software must be used. Connect
the laptop to the smart level transmitter signal loop
to be validated and start the software according to the
instructions provided at the beginning of this Section.
B. At the Main conguration screen observe the Level
Calibration, Lower Capacitance, and Upper Capacitance
values and the Lower Level and Upper Level values.
Select an NPO Capacitor (which can be NIST traceable,
if desired or required) that falls somewhere mid-range.
Example: See Fig. 3-18. If Lower Capacitance is 50pF
and Upper Capacitance is 2000pF, that corresponds to
a Lower Level and Upper Level of 0-10 feet. Select an
NPO Capacitor of approximately 1000pF. [Drexelbrook
401-6-8 Capacitor Substitute Box may also be used; it is
traceable to NIST].
C. Connect the NPO capacitor selected from the last
step to the Probe and Ground connections at the
transmitter (with coaxial cable from sensing element
disconnected).
D. Select Real Time View on the PC software Menu Screen
(F4 on your keyboard) See Fig. 3-19. The display should
show the Capacitance as the value of the NPO Capacitor
(within the capacitors tolerance), and the LEVEL
should display close to the mid-range of the Lower and
Upper Level from the Level Calibration eld. The Loop
Current and the Percentage will also reect the values
that are generated by the NPO Capacitor. Add to the
scratch pad of the Menu Screen the value of the NPO
capacitor that you used. If desired, this information can
be printed out for le or record purposes. Mark or Tag
this capacitor* to correspond to this specic transmitter.
Put the capacitor in a safe location for use in subsequent
testing and validation.
E. By placing the same exact capacitor* on the RF
transmitter's Probe and Ground terminals and observing
the signal output generated by this capacitor, it can be
veried that the transmitter is operating properly and
that the calibration information is the same as during
the initial set up.
Every capacitor manufactured will generate a slightly
different capacitance value within its specied tolerance.
By marking the capacitor and using only this capacitor for
testing and validating the AMETEK Drexelbrook Universal
III Transmitter, the system should produce repeatable
results within transmitter specications.
Figure 3-18
Capacitance on Menu Screen
Figure 3-19
Real Time View Pop-up from
Menu Screen