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APPENDIX A
While Smith meters are basically the same in
principle, some differences exist in the design of the
various models. Figure 1 shows the principle of Rotary
Positive Displacement Meters. Figures 2, 3 and 4 show
differences in design.
It will be seen from the illustrations that the rotor
positioning adjustment of the Meters in Figure 2 is made
at the bottom of the meter. In Figures 3 and 4 the rotor
positioning adjustment is made at the top of the meters.
It is to be noted that the rotor shaft in Figure 4 extends
through the meter base. This is not the case in Figure
3.
Double Case Meter construction differs from Single
Case construction in that the measuring unit is encased
in a high pressure outer housing.
To obtain maximum service from Smith Meters, it
is suggested that detailed records be maintained on
each. Data such as meter model, capacity, serial
number,
meter
clearances,
progressive
totalizer
readings, meter factor or adjustment and other pertinent
data should be recorded.
Such information is an excellent guide in scheduling a
preventive maintenance program.
OPERATING INSTRUCTIONS
1.
Large volumes of air capable of extensive
destruction can be unknowingly compressed in a
dry line by the pump at the first attempt to flood
a -new system, therefore, valves must be
opened very slowly to avoid damaging the
meter by over-speeding. Always have an up
stream valve closed before operating a set stop
valve the first time.
2.
Valves should be handled in a cautious manner
after a meter has been put into service to avoid
unnecessary abrupt stops. Sudden valve
closure causes severe line shock creating
pressures many times the normal operating
pressure. This may result in damage to the
meter and other equipment.
3.
Reset Type Counters must not be reset when
the meter is operating.
4.
The "ticket securing pin" in a printer head must
be in the down or locked position when the
meter is operating.
5.
The normal flow range of a meter is from its
maximum
rated
capacity
to
20%
of
its
maximum rated capacity, example: 100 GPM
maximum 20 GPM minimum.
6.
Meter calibration is effected by adjusting the
calibrator dial or knobs whichever the case may
be. Calibration may be changed in increments
of 1/20 of 1%. The calibrator adjuster is
concealed under a small cover fitted to the
register adapter.
7.
Only meters equipped with "G " calibrators can
be operated in either direction. Standard meters
are assembled for right hand flow direction
unless otherwise requested by the customer.
Refer to Pages.8 & 9 for reversing instructions.
8.
If a meter has been idle for a considerable time,
it is considered good practice to drain it of
possible water and sediment before restoring it
to service.
A9-20
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