Hydrological Services Pty Ltd
Data Logger Model ML1-420
©
Copyright
ML1-420 100-3
Issue 1.00 6 Apr, 2011
1. Introduction
The Hydrological Services MiniLog Data Logger ML1-420 has been designed using surface
mount technology to provide a very small, ultra low power and reliable data logger that can
be used in harsh environments for extended periods. Flash memory technology has not only
been used for data storage but also for program storage - which provides secure non-volatile
data storage as well as the unique capability of software download as new software features
and revisions become available. The logger can be connected to a standard Tipping Bucket
Rain Gauge OR any device that requires a contact closure to be monitored – it monitors the 4-
20mA signal from a water level transducer, an external 12V battery, the internal battery and
the ambient temperature inside the MiniLog enclosure. The communication features allow for
very flexible operation directly connected to a computer. The unique on-board help feature
allows the user to obtain a list of commands with syntax. The ultra low power allows the
logger to be powered from an internal 3.6V AA lithium battery for 2 years or a 1.5V AA
alkaline battery for 1 year. The indicator LED flashing once a second as a heartbeat, gives the
user confidence that the MiniLog is alive and well.
LAN / WAN
PORTABLE PC
OR
ML1-420
Logger
Logger returned
Unload at site
PC
TBRG
(If applicable)
OR
Communication
Interface
PSTN, GSM, Satellite
River Height
4-20mA Sensor
