Delta OHM HD33[L]M.GSM, Operating Manual

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HD33[L]M.GSM
- 7 -
V1.10
4 MEASURING PROBES
Relative humidity and temperature :
For the measurement of relative humidity and temperature, the combined probe HP3517TC2
with NTC 10K Ω @ 25 °C temperature sensor is used. Alternatively, to the same input can be
connected the temperature only probe TP350NTC2 .
The outdoor installation of the probe requires HD9007A-1 or HD9007A-2 protection against
solar radiations. Replacement of the humidity probe requires recalibration of the
instrument in line with the new probe .
Atmospheric pressure :
The optional sensor, if present, is inside the instrument.
Rainfall quantity :
The HD2013 (area 400 cm
2
), HD2013R (area 400 cm
2
, with heating), HD2015 (area 200 cm
2
)
and HD2015R (area 200 cm
2
, with heating) tipping bucket rain gauges and the HD2016 (area
400 cm
2
) and HD2016R (area 400 cm
2
, with heating) weighing rain gauges are available.
Solar radiation :
The pyranometers LP PYRA 02, LP PYRA 03, LP PYRA 10, LP SILICON-PYRA 04, etc. with mV
output signal can be connected.
Wind speed and direction :
For the measurement of wind speed and direction, the cup anemometer HD54.3 and the
wind vane HD54.D are used.
The cup anemometr and the wind vance require a minimum threshold speed (typically 1÷1.5
m/s) to provide reliable indications. If the speed falls below the minimum threshold, the
direction indication is frozen at the last value measured, while the speed indication is blocked to
the threshold value or to zero (the behaviour is configurable by using the HD35AP-S software).
Other quantities :
For measuring other quantities, models with an analog input (option X ), to which any
transmitter with 4…20 mA active or passive current output can be connected, are available.
Probes connections :
Rain gauge Wind vane
Pyranometer 4 … 20 mA input
Anemometer
Data logger connectors viewed from outside
+
(pin 1)
Connector
reference
Connector
reference
-
(pin 2)
+
Power supply
(pin 1)
GND (pin 3)
+
Signal
(pin 2)