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2 electrical specifications, 1 current, Electrical specifications – Campbell Scientific CS650 and CS655 Water Content Reflectometers User Manual

Page 12: Current

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CS650 and CS655 Water Content Reflectometers

5.2 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 1 – 10

sensors connected to the same datalogger

control port

Electromagnetic

Compatibility:

Œ compliant (EMC compliant performance

criteria available upon request)

Meets EN61326 requirements for protection

against electrostatic discharge and surge

External RF sources can affect CS650

measurements. CS650 circuitry should be

located away from radio transmitter aerials

and cables, or measurements ignored during

RF transmissions.

5.2.1 Current

Active (3 ms):

45 mA typical @ 12 Vdc

(80 mA @ 6 Vdc, 35 mA @ 18 Vdc)

Quiescent:

135 µA @ 12 Vdc

Average Current Drain:

I = 0.09n + [3.5 + 0.024(n-1)]n/s

I = average current in milliamps

n = number of CS650’s

s = number of seconds between

measurements

(see FIGURE 5-1)

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