MODEL 2200-3000 RETROFIT OPEN STREAM CURRENT METER / PAGE 3 of 7
Supplement to Model 3000 Instruction Manual
7. Conduct the standard AA meter spin test as defined by the USGS instructions. When properly
installed and adjusted, the AA meter conversion should provide at least a slight increase in the normal
spinning time.
8. Install the "O" Ring (2200-011) in the top of the 2200-A2 Adapter.
9. Place the Sensor (2200-A) on the adapter and tighten the sensor mounting nut (2200-A3) finger tight
only. The sensor should not rotate when mounting nut is tightened. If it does tighten the front yoke
screw a bit more (see step 4 above) and check that the "O" ring is properly seated.
10. Give the meter a second spin test to make sure all installations are correct and that operation is
satisfactory.
PYGMY METER
1. Remove contact chamber cap, binding post nut and binding post body, leaving only the nylon bushing
in place in the yoke. Install the furnished
10-32 x 1/4"
screw tightly in the bushing.
2. Remove the bucketwheel pivot shaft.
3. Unscrew the upper rotor shaft from the bucketwheel and replace it with the new one
(2200-A5)
.
Tighten the new shaft only by using the wrench
(.05" allen wrench)
inserted in the hole in the rotor
shaft to avoid damage to the bearing surface.
4. Remove Upper Bearing (bronze part) from the yoke. This part is not necessary and will prevent
proper installation of the adapter if not removed.
5. Install the Pygmy meter Adapter
(2200-A1)
by threading it into the upper yoke arm (formerly the
contact chamber cap threads). Carefully insert the top of the new bucketwheel shaft through the hole
in the adapter bottom while you thread. Tighten the adapter onto the yoke by use of the allen wrench
horizontally through the holes in the upper threads of the adapter. Make sure the adapter is tight to the
yoke otherwise removal of the sensor nut may unscrew the adapter if the threads are a bit snug.
6. Re-install the lower pivot shaft adjusting it vertically as necessary; centering the bucketwheel in the
yoke as much as possible.
7. Using the brass blade driver supplied install the Fiber-Optic Carrier Rotor
(2200-A14)
through the top
of the Adapter and onto the threads of the new rotor shaft. DO NOT TIGHTEN TOO TIGHT TO
AVOID STRIPPING THREADS.
The top of the Fiber-Optic Rotor must not be above the
shoulder inside the Adapter.
8. Conduct a spin test. When properly installed and adjusted, the spinning time should be at least as long
as that previously achieved before conversion. Note the rotation of the fiber-optic rotor. It should be in
the center of the adapter and must never come in contact with the sides of the adapter.
See Pygmy
Meter Retrofit Problems, ahead, and refer to the notes for corrections if contact is being made. Do not
operate the meter if fiber-optics rotor makes contact with the adapter!
9. Install the "O" Ring
(2200-011)
in the top of the Adapter and place the Sensor on the Adapter and
tighten the Sensor Retaining Nut
(2200-A3)
on the yoke finger tight only. Do not operate the sensor
without an “O” ring as it helps keep the optics from contacting the rotor should tolerances be wrong.
10. Conduct a second spin test to confirm all installations and adjustments are satisfactory.
NOTE:
Keep the adapter protectors
(2200-A16)
on the meters when the instrument is not in
use. These protect the adapter threads, prevent loss of the "O" rings and keep dirt out of the
sensor.
CARE AND MAINTENANCE OF THE MODEL 2200-3000 SENSOR
1. The proper operation of the Model 2200 Sensor depends on the transmission of an infrared light beam
generated by the light-emitting diode in the Sensor through 180° loops of rotating fiber-optic bundles
