Campbell Scientific CS445 Liquid Level Sensor - Manual (Page 7)

CS445 Liquid Level Sensor
3
tubes should be inspected regularly (i.e., every two months) and historical
information will help to baseline desiccant replacement requirements for a
given application/climate.
Absolute pressure (Non-Vented) units do not require a desiccant chamber. If
the cable incorporates a vent tube, the vent tube is heat sealed at both ends
prior to shipment and must remain sealed.
Remember that although the CS445 is designed to be a rugged and reliable
device for field use, it is also a highly precise scientific instrument and should
be handled as such. There are no user serviceable parts and any attempt to
disassemble the device will void the warranty.
3.2 Installation Guidelines
The CS445 is designed for water level measurement. Typical applications
include agricultural water level/flow, water wells, lakes, streams and tanks. If
the device is to be installed in a liquid other then water or in contaminated
water, check the compatibility of the wetted materials.
The Transducer may be installed in any position but it is calibrated and tested
in the vertical orientation, as it would normally be suspended.
Never suspend the transducer from the connections at the top end of the cable.
When suspending the device, in a well for example, a proper strain relief
should be attached around the cable jacket and properly secured at the well
head.
Although the cable jacket is made from a thick, tough polyurethane formation,
care should be taken to avoid cable damage. Further, sharp bends or excessive
pinching of the cable can cause damage and may pinch off the vent tube
causing measurement errors in the case of gauge pressure (Vented) devices.
Do not drop the instrument or allow it to “free fall” down a well as this may
damage the device.
Never attempt to disassemble the transducer as this will void the warranty.
4. Wiring
Color Function CR200 Series CR23X, CR10(X),
CR510, CR500
Red + Power. 8 to 24 VDC Battery + 12V
Black Ground G G
Brown SDI-12 Data Line C1/SDI-12 Control Port 1-8
Clear Shield. Not connected
to transducer body G G
5. Programming Example
The CS445 uses an SDI-12 compatible hardware interface and supports a
subset of the SDI-12 commands. The most commonly used command is the
aM! command, issued by the datalogger. Here, ‘a’ represents the sensor
address (0 – 9). The communication sequence begins with the datalogger