HyQuest Solutions Pty Ltd
Point Velocity Display - Model PVD100
©
Copyright
12
Issue 1.00 4 Apr, 2007
MAGHEAD
CATWSKR
NORMAL
SLOW
ON-BUZR
OFF
4.3.4
Magnetic Head / Cat whisker
Allows selection between a Magnetic Head contact or a Cat
Whisker contact switch. Use the FUNCTION button to select
this menu, then press SELECT to toggle between Magnetic
Head or Cat Whisker contact. Press ON/OFF to return to the
main display or press FUNCTION to step to the next menu
item.
One of the most important operating features of the
PVD100
is the ability to signal process
each contact closure. Contact closures from any type of meter are inherently noisy causing
miscounting or double counting. The
PVD100
samples the input signal from the connected
meter and examines the signal to determine if a contact closure has occurred and if successive
signals are of the same characteristics. The
PVD100
then determines contact closure
conditions and either counts the signal closure or eliminates the condition as a noise pulse and
does not count the signal. For cat whisker contacts, this becomes extremely important since
cat whisker contacts offer the poorest quality for marking and counting rotations.
4.3.5 Normal
/
Slow
Use the FUNCTION button to select this menu, then press
SELECT to toggle between Normal or Slow. Press ON/OFF
to return to the main display or press FUNCTION to step to
the next menu item.
The
PVD100
offers (2) modes of operation, i.e. NORMAL
and SLOW speed mode. NORMAL is selected for meter
rotations >0.076 m/sec while SLOW mode is for velocities below 0.076 m/sec. To improve
noise rejection, the sample rate of the input signal at the SLOW speed mode (lower
velocities) is 1/10 of the sampling rate that occurs during NORMAL mode. This slower
sampling rate improves performance for back rotations and corroded whisker contacts at
extremely low meter cup rotations. It is important to know that the
PVD100
offers
operational overlap at this 0.076 m/sec velocity selection in either mode and therefore it is not
necessary for the operator to know precisely the velocity of water for selecting either mode.
When in SLOW mode, the status LED flickers, and the sounder beeps longer whenever the
whisker contacts are made.
4.3.6 Buzzer
On/Off
Use the FUNCTION button to select this menu, then press
SELECT to toggle between Buzzer
On
or
Off
. Press ON/OFF
to return to the main display or press FUNCTION to step to
the next menu item.
