| Start Date | Start Time | End Date | End Time |
|---|---|---|---|
| 05/30/1997 | 1500 | 12/31/1997 | 1520 |
| Subject: | SGP/EBBR/E19 - Battery Voltage Drop |
| DataStreams: | sgp15ebbrE19.b1, sgp30ebbrE19.b1, sgp5ebbrE19.b1 |
| Description: | EBBR battery voltage at E19, El Reno, OK declined to lower than acceptable levels after long periods of clouds after initial installation. The low voltage condition worsened as Autumn progressed. In November 1997 the battery tested okay, but would not hold sufficient capacity at night or during extended periods of clouds to keep the voltage high enough for the EBBR to work properly. At my request, the battery was replaced with a brand new battery on 31 December 1997. The new battery is presently maintaining voltage level at night. The voltage dropped to 10 volts or less many days before the battery change. Voltages less than 10.3 volts affected a wide range of measured values, but at different times. When the voltage was much below 10 volts the home signal became very large (several volts), a quirk of the AEM circuitry. At various times, latent and sensible heat fluxes, soil temperature, air temperature, relative humidity, vapor pressure, wind direction, soil heat flux plate output, home signal, and atmospheric pressure (at least) were not reported correctly by the CR10 datalogger. At least the sensible and latent heat fluxes should be considered to be incorrect when the battery voltage is less than 10.3 volts. The battery voltage is found in the 15 minute data. |
| Suggestions: | |
| Measurements: | sgp30ebbrE19.b1: more
sgp15ebbrE19.b1: more sgp5ebbrE19.b1: more |