52202 Electrically Heated Rain and Snow Gage
8.1 Maintenance
The rain gage should be inspected periodically. Accumulated dirt and debris
should be cleaned from funnel, screen and bucket assembly. Electrical
connections should be inspected and cleaned. Leveling screws may be
readjusted at this time.
Periodic recalibration may be desirable to ensure measurement accuracy. The
following calibration check is advised every 12 months.
1.
With the rain gage properly leveled, slowly pour a measured volume of
water into the collection funnel. The rate should be about 10 ml per
minute which is approximately 1 inch per hour. The bucket should tip five
times for each 10 ml of water. For example, 100 ml should give a count of
50 ±1. Bucket tips may be counted manually or with a counter connected
to the rain gage terminals.
2.
If the count shows an error of more than 2%, adjust the calibrating screws
to correct the error. Raise the screws if the count is low, lower the screws
if the count is high. Always adjust both screws equally.
8.2 Troubleshooting
Symptom: No Precipitation
1.
Check that the sensor is wired to the pulse channel or control port
specified by the pulse count instruction.
2.
Verify that the Configuration Code (Switch Closure), and Multiplier and
Offset parameters for the Pulse Count instruction are correct for the
datalogger type.
3.
Disconnect the sensor from the datalogger and use an ohm meter to do a
continuity check of the switch. The resistance measured at the terminal
block on the inside of the bucket between the black and white leads should
vary from infinite (switch open) when the bucket is tipped, to less than an
ohm when the bucket is balanced.
9. Attribution
Santoprene
®
is a registered trademark of Exxon Mobile Corporation.
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