CS650 and CS655 Water Content Reflectometers
6
6.1 Electrical Specifications
Sensor Output:
SDI-12
Serial RS-232
Warmup Time:
3 s
Measurement Time:
3 ms to measure
600 ms to complete SDI-12 command
Power Supply
Requirements:
6 Vdc to 18 Vdc
Must be able to supply 45 mA @ 12 Vdc
Maximum Cable Length:
610 m (2000 ft) combined length for up to 25
sensors connected to the same datalogger
control or
U
terminal
1
Electromagnetic
Compatibility:
View EU Declaration of Conformity
documentation at
External RF sources can affect CS650
measurements. CS650 circuitry should be
located away from radio transmitter aerials
and cables, or measurements discarded
during RF transmissions.
Active Current Drain
(3 ms):
45 mA typical @ 12 Vdc
(80 mA @ 6 Vdc, 35 mA @ 18 Vdc)
Quiescent Current Drain:
135
µ
A @ 12 Vdc
Average Current Drain:
I = 0.09n + [3.5 + 0.024(n-1)]n/s
I = average current in milliamps
n = number of CS650s
s = number of seconds between
measurements
1
Campbell Scientific recommends using separate terminals when possible.