Specifications

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a separate enclosure. The s econd is to curb the damage done by rough handling or
vandalism.
6. The device must support all of the following interface options: one SDI-12 commu-
nication port, three analog input ports, and two digital I/O ports. The analog port
must su pp ort 0-20mA current measurement and an auto-ranging voltage m easurement
capable of measuring zero to ten volts with 12-bit accuracy.
7. The device must support an RS232C serial interface so as to connect to a PC or long
distance radio. Some discussion was invested into incorporating a USB port instead
of an RS232 port. US B is fast becoming a more common interface then RS232, but
USB uses more power and was therefore d iscarded with the caviot that if a processor
could be found that supports USB, it could be ad ded as an other supported interface.
8. The device must contain a real-time clock (RTC) with battery-backup for unbroken
operation for longer than five years of shelf life.
9. The device must support programmable logging intervals with one minute resolution.
All sensors are expected to be able to measure at or within this interval.
10. The device must support a common flash memory card interface for extended memory
applications and virtual device networking (VDN).
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11. The device must have an embedded ZigBee Mesh radio to support a scalable inter-
device network for au tomatic data routing for centralized data storage. The device
must support multiple network personalities to make possible the easy integration
of this device anywhere in the network. The ab ility to change the radio’s function
eliminates the n eed for Acclima to p rovide specific coordinator, router, or endpoint
loggers.
12. The d evice must have two easy-to-use methods for configur ing the device. One of these
ways is to use a LCD driven user interface as a direct way to access device function
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VDN is a way to view key files form multiple devices without actually connecting to the real-time
network. An image of the device is stored to the memory card.