Geokon 8020-42, Руководство по установке, Страница: 7 / 13

3
3. CONFIGURATIONS
3.1 Micro-10 Datalogger Configuration
The 8020-42 can be incorporated as the vibrating wire interface in a Micro-10 Datalogger
system, taking the place of the Campbell Scientific Inc. AVW-1. In order to configure the 8020-
42 for the Micro-10 Datalogger, internal jumpers JP1, JP2 and JP3 must be set across pins one
and two. Remove the cover of the 8020-42 and set the jumpers:
JP1 JP2 JP3
Figure 2 - Internal Jumper Settings for Micro-10 Configuration
Between readings, the 8020-42 will be “asleep”, drawing approximately 20
µ
A from the 12V
system battery.
When it is time to take a reading, the datalogger will set C1..C7 (ENABLE) high in order to
enable the respective multiplexer, and the individual channels are clocked by pulsing C8
(CLOCK) high.
When “ENABLE” and “CLOCK” are both high, the 8020-42 will wake up and wait for the
swept frequency excitation signal to appear at EX. The 8020-42 will track and apply this swept
frequency to the VW gage. Once the swept frequency is complete, the 8020-42 will lock onto the
returned VW signal and maintain excitation by applying one excitation pulse for every 16 cycles
of VW frequency. The VW frequency is provided as both a 200mv(pp) signal at F1, and as a
5v(pp) 50
Ω
output at F2
It is helpful to add a small amount of delay (
≈
0.5 Sec. ) from the time that the swept frequency
excitation ends and the time that the reading is taken. MultiLogger software, ver. 1.4.0 and above
provides this delay when selecting a gage type that has the letters sca included within it, e.g.,
4500sca, 4700sca etc.
PIN 1
PIN 2
PIN 3