Specifications

13
and has been proven by years of field work.
Addressing the requirement list discussed in section 1.3, this logger does support mul-
tiple power modes that enables it to conserve battery life. Its power modes are as follows:
.2mA inactive, 3mA active with no radio, and 20mA to 75mA active with radio. These are
satisfactory power specifications. The logger also satisfies the integrated rad io specification
and database requirements as well. However, the logger fails the ease of use stipulation. To
use a Campbell logger, one must know basic electrical principals and wire up the sys tem
based on these principals. Then one must learn the CRBasic or Edlog programming lan-
guages. To establish a wir eless network, the user must then manage the PakBus protocols
on every logger in the system. All of these tasks are technical in n atur e. Th is device does
not have a built-in user interface. This logger also fails the ruggedness requirement because
it isn’t weatherproof, and requires a separate enclosure to ensure continued operation in any
of the rated conditions. Finally, it fails on cost. A u s er must purchase the logger and the
proprietary software to interface to the logger and other Campbell Scientific devices. The
logger cost is $630 (2007), together w ith batteries, enclosure, and software is over $1,400.
Software costs only apply to the first system, so the site cost of a system us ing a CR200 is
around $1000 per node, falling outside the stated cost requirement.
2.5.2 Sutron Systems
This Virginian company [30] is also a world renowned maker of rugged data logging
and measurement equipment. They specialize in building very rugged datalogging plat-
forms that communicate us ing high power RF and satellite communication. Some of the
equipment manufactured by this company has been deployed in harsh envir onments such
as the Himalayas, South American rain forests, and Antarctica. Sutron manufactures six
different logging platforms with various sensor interfaces most of which were designed for
large amounts of instrumentation at one location.
The 8210 logger (see fig. 2.3) was selected as th e closest match for this application. It
boasts 62,000 to 190,000 volatile measurement readings possible and an external PCMCIA
to expand memory s ize to a gigabyte. One of three methods can be used to program