Instructions
5
CLEANING AND CARE
Avoid the eects of moisture (spray or rain water), dust as well as direct insolation on the device.
Clean the device exclusively with a dry linen cloth; in case of heavy dirt accumulation, it may be
slightly moistened. Do not use any detergents containing solvents.
GENERAL
Elektrotechnik Schabus GmbH & Co. KG is not liable for damages and/or losses of any kind such as
individual damages or consequential damages brought about by the water detector not issuing an
alarm despite any changes in water conditions.
INTENDED USE
The active water sensor SHT 8824 is supplied with an operating voltage (SELV / PELV) and requires
approx. 4 mA dry and approx. 20 mA wet. It is wired as a constant current sink and its power con-
sumption allows a clear distinction between wet and dry. It is so sensitive that even „normal“ distilled
water (according to VDE 0510-5, hardware store quality) can be reliably detected. The sensor is sup-
plied with the operating voltage directly via the signal lines. According to the denition of the analog
current interface, an active input is required for a passive 2-wire sensor.
If the current falls below 3 mA during operation, a sensor failure or cable break is reliably detected.
Technical specications SHT 8824
item number 200324
for active inputs measuring transducer / transducer for 2-wire sensors (industry standard)
Load up to 500 Ω at Ub < 24 VDC
up to 700 Ω at Ub >= 24 VDC
operating voltage Ub 10...30 VDC, typ. 24 VDC, SELV/PELV
Loop current dry 4 mA @ Ub = 24 V, real 3.6 - 4.2 mA depending on operating voltage
Loop current wet 19 - 20 mA @ Ub = 24 V, depending on conductivity of the medium
real 14.1 - 20.3 mA, depending on operating voltage and conductivity
highest loop current max. 21 mA @ Ub = 30 VDC and conductivity ƙ = 1.4 x 10
6
S / m
lowest loop current min. 3.6 mA @ Ub = 10 VDC and sensor = dry
Degree of protection IP68, protection against water jets for 30 minutes, cable briey waterproof
Temperature range -15 ° C ... + 50 ° C max.
Connection cable 2-wire - LIYY - 2x 0.14mm² - unshielded - Ø 3.5mm - white - 4 meters long
Line assignment white negative connection / 0 V / minus
brown positive connection / Ub / plus
Assembly base, edges, grooves, corners:
screw hole Ø 3.2 mm, 9 mm long, reinforced with aluminum
Usage in regularly dry surroundings for rare water events
Material ABS body, aluminum screw hole, V2A contacts, encapsulated with Wepuran
pos.
neg.
sensor
operating voltage
Loop current in mA (without load)