GHM Delta OHM HD2013, Operating Manual

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HD2013
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V1.6
1 INTRODUCTION
The HD2013 is a reliable and sturdy tipping bucket rain gauge, built entirely from cor-
rosion resistant materials in order to guarantee its durability. So as to ensure accurate
measurement even with low temperature climatic conditions or during and after pre-
cipitations of snow, a version with heating which is automatically activated around
+4
°C has been developed so that snow deposits and ice formations are prevented.
The rain gauge is formed by a metal base on which a tipping bucket is set. The rain
collector cone, fixed to the aluminium cylinder, channels the water inside the tipping
bucket: once the predefined level is reached, the calibrated bucked rotates under the
action of its own weight, discharging the water. During the rotation phase, the nor-
mally closed reed contact opens for a fraction of a second, sending an impulse to the
counter.
The quantity of rainfall measured is based on the count of the number of times the
bucket is emptied: the reed contacts, normally closed, open at the moment of the rota-
tion between one bucket’s section and the other. The number of impulses can be de-
tected and recorded by a data logger (e.g. HD2013-DB) or by a pulse counter.
The rain gauge is available with optional analog output at choice between 4…20 mA
(HD2013… A …) or 0…10 Vdc (HD2013… V …) or with optional SDI-12 digital output
(HD2013… S …).
The version with 4…20 mA output and the version with SDI-12 output require 7…30 Vdc
power supply. The version with 0…10 Vdc output requires 13…30 Vdc power supply. The
versions with analog or SDI-12 output are equipped with a backup battery that allows
maintaining the rainfall information even after short power supply outages (at least 10
seconds for the versions with analog output, approx. 5 minutes for the version with
SDI-12 output).
A removable filter for periodic cleaning and maintenance is inserted in the water col-
lector cone so as to prevent leaves or other elements blocking the end of the hole.
For a better water flow, the collecting cone is treated with a non-adherent product.
In the version with heating HD2013… R … , the heating circuit operates with 12 Vdc or
24 Vdc direct voltage ( to be specified when ordering ) and absorbs about 165W.
Heating is activated 4 °C.
When submitting your order , upon request a bird dissuader, made of eight 3 mm
diameter spikes, 60 mm in height, can be installed on the rain gauge.