D-1401 & D-1402 Portable Metering System Installation and Operation Guide • 03-17
8
When using a D-1402 system, the individual top and bottom turbine
frequencies can be observed as a reference to the amount of rotational swirl
that is present at each insertion depth measurement point.
To utilize this function, set the middle switch to
“SELECT”
. The right switch
can then be toggled between
“TOP”
and
“BOTTOM ”
to display the
individual turbine frequencies.
A stable, uniform flow velocity at the measurement depth will be indicated by
having the same or very close (+/- 10%) to the same frequency reading on both
the top and bottom turbine.
A significant difference between the top and bottom turbine frequency
numbers will indicate the presence of flow turbulence and swirl at the
measurement depth. The top and bottom turbines rotate in opposite directions.
Turbulence and swirl will either increase or decrease the speed of rotation of
one of the turbines and will have the opposite effect on the other turbine.
2.5
SYSTEM STORAGE AND M AI NTENANCE RECOM M ENDATI ON
1. Always store the system in its carrying case when not in use.
2. Before long-term storage of the system, blow all excess water from the flow
meter turbine assembly and wipe the flow meter stem assembly dry with a
clean cloth.
Do not put any lubricants on the turbine assembly.
Oil based
lubricants will damage the flow meter’ s o-ring seals.
3. If storing the system for long periods of time, remove the 9-volt battery from
the Display Module and store it separately.
4. The flow meter’ s hot tap adapter should be pushed completely down over the
turbine assembly and locked so that the turbines are protected when moving
the system to a new location or when storing the system.
5. The flow meter turbines, bearings and shafts can be cleaned using a 30 percent
white vinegar to 70 percent tap water solution. An old toothbrush can be used
to lightly brush around the bearings. Rinse with clean water and blow off
excess water before storing.
2.6
FLOW M ETER I NFORM ATI ON