Xylem H-339 - Manual (Page 6)

Chapter 1
Operation
H-339
Operation 1-1
Introduction
The W
ATER LOG H-339 is a smart SDI-12 sensor that returns date, time and position information. ®
It is easy to use and works with any data recorder / logger with an SDI-12 interface. The “Serial-
Digital Interface” is ideal for data logging applications with the following requirements:
! Battery powered operation with minimal current drain
! Low system cost
! Up to 200 feet of cable between a sensor and the data recorder
The H-339 has the following features:
! Reports date, time and position
! Low power for battery powered applications
! Fast time and position acquire times.
The H-339 consists of a GPS module with a 10 foot cord, an SDI-12 interface board, GPS Utility
Software, and this manual.
When bought by itself, the H-339 SDI-12 interface board is packaged in a rugged, water resistant
enclosure. Wire feed through connectors (Hubble Connectors) located on each end provide easy
access to the internal terminal block connectors. One for the GPS module cable and the other
provided for an SDI-12 cable.
When bought with an H-222SE-300 GOES radio system, the H-339 SDI-12 interface board is
mounted inside the GOES radio enclosure. This GOES radio enclosure will have two extra Hubble
connectors for the GPS module cable and for an SDI-12 cable.
Installation
The GPS module must be mounted where it has a clear view of the sky. Power lines and other minor
obstructions are not a problem, however thick tree cover can and will prevent the receiver from
acquiring valid time and position data. Mount it as flat as possible to give it the best view of the sky.
If the H-339 main interface is not packaged with the GOES radio, it may be mounted near the GPS
module or near the data logger. If it is packaged with the GOES radio then the GOES radio
placement dictates the location of the H-339 SDI-12 interface board.