MAWS HydroMet™ Systems for Meteorological and Hydrological ...

Chapter 2 __________________________________________________________ Main Components
The printed board uses the latest SMT and CPLD (Complex
Programmable Logic Device) technologies and is uniformly coated for
better protection and reliability in high humidity environments.
Each sensor input has a varistor (VDR) protection against induced
transients. The maintenance terminal connection (RS-232, COM0)
also has transzorb diodes in its inputs.
When long signal cables are needed, these will be equipped with
optional devices for surge voltage protection. These surge arrestors
consist of a combination of VDR, gas-filled discharge tube, transzorb
diodes and coils, thus providing excellent protection. These DIN-rail
mountable devices are easy to change without any special tools.
Compact Flash Memory Card Option
The QML201 Logger has a place for a standard Compact Flash
memory card, the same as is used for example in a digital camera, for
logging a large amount of data. CF cards offer logging capacity from
32 Mbytes to hundreds of Mbytes at a very economical cost. CF cards
do not need any back-up battery for preserving contents practically
indefinitely.
The data is logged into the daily files making it easy to locate any
particular data set e.g. for further analysis.
Compact Flash Memory Card Option
These cards can be read directly to the PC. Several different types of
readers are commercially available at any PC or camera store; internal
PCMCIA (PC-card) readers and external readers connected to the
USB or parallel port of a PC.
VAISALA ________________________________________________________________________ 13