Vaisala Hydromet Data Collection Platform User Manual
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User's Guide ______________________________________________________________________
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The QML logger is a complete AWS data logger designed on one
printed board only. This board contains a 32-bit Motorola CPU for data
processing and 10 differential (20 single-ended) analog sensor inputs
(these can also be used as digital inputs). Moreover, there are two
frequency sensor interfaces, a 24-bit A/D converter, 3.3 MB of secure
Flash memory for data logging, as well as an excitation power supply
for sensors and a charger for the internal backup battery. The last item
mentioned is not needed in systems where a backup battery with higher
capacity is used.
The board uses the latest SMD (Surface Mount Device) technology and
is conformal-coated for improved protection also in high humidity.
Each sensor input has a varistor (VDR) protection against induced
transients. The serial line connections, that is, RS-232 labeled as COM0
and RS-485 labeled as COM1, have two level ESD protection circuits
with VDRs directly at input pins.
The cover of the logger can be removed for installing the battery and for
resetting the weather station. In
without the cover and the optional communication modules.