土壤水份

E-Sensors

Electronic as well as analog sensors constantly measure the suction tension of the tensiometer. The current measurement is either digitally displayed or used for switching purposes (by units with appropriate connecting port). The actual pressure gauge itself is usually integrated within a transformer and requires it𠏋 own electrical supply.

The distinct advantage of the electronic tensiometer is the potential to take moisture measurements constantly with a corresponding recording of data and the possibility to set variable switching points.

Suitable for use with following irrigation systems:	no restrictions
Accessories required:	Tensiometer bottom part with screw-threaded neck piece (GL 14) + Digital unit with appropriate software: for example, irrigation computers for analog sensors, climate computers, PC, data loggers (also see TensioSave and TensioCheck)

Technical Description

Housing: cylindrical casing with short stem, ?26 mm, height 70 mm , with white protective covering (Shrink-Wrap); Weight ca.. 27 g
Pressure Gauge: piezometer sensitive pressure sensor with differential pressure measurement, accuracy (in % of measurement range): linearity and hysteresis ?0.2, temperature sensitivity (0-50?with reference point of 25蚓): ?0.4? accuracy of repetitions: ?0.2, consistency over 1 year: ?0.1, operating temperature: 40蚓... +85蚓, maximum pressure: 1.3 bar (350 hPa), 2 bar (1000 hPa).

Tensiometer Connection: Screw cap with replaceable O-ring seal (7 x 2.5 mm) for directly attaching onto the tensiometer, screw-thread: GL 14.
Electrical Connection: shielded cable with permanent connection (CV2 with plug connection on sensor casing), anti-kink cable connected on casing, cable length 4.8 m, lead connections: white = elec. supply (+), green = elec. supply (- ), brown = signal (+/- ), yellow = signal (+), black = ground; protection type: IP 65, with protection against reverse connection.

Distinguishing Characteristics

Model		C		CV		CV 2		CV 5		CVD
Article number		1604	1605	1606	1607	1608	1609	1610	1611	1612	1613
Measurement range	hPa	350	1000	350	1000	350	1000	350	1000	350	1000
Measurement signal		4-20 mA		60 mV	90 mV	0.1-2.5 V		0.1-4.8 V		0.1-4.8 V
Electrical supply	V DC	14-26		5... 20 const.		5,2-15		5,2-15		5... 15 const.
Number of leads		2		4		3		3		3
Max. cable length		(any)		Loss of voltage should be taken into consideration.
Reference voltage	V	-		12		-		-		5
Electr. consumption	mA	Max. 20		3		< 5		< 5		< 5


1604 - 1101	1605 - 1203 - 1204

Suggestions, Special Features

C	Standard model, especially trouble-free, however, has high energy consumption; measurement range 350 hPa for peat substrate in container plantings (finer measurement graduations, however, usually this is unnecessary; measurement signal somewhat more sensitive).
CV	Sensor without measurement transformer, so relatively inexpensive; signal proportional to the electrical voltage supply, therefore, a constant voltage supply is required; sensors should be calibrated on location (due to loss of voltage), beware of disturbances. Sensor for TensioCheck.
CV 2	Special model with small voltage signal, low energy consumption, appropriate for use with batteries, plug for cable connection on sensor.
CV 5	Also for use with batteries, finer measurement graduations, low measuring sensitivity.
CVD	Like Model CV 5 however, without voltage regulator?signal proportional to voltage supply, constant voltage supply important; sensor for TensioSave.