Precision Water Level Instrument
Unidata Manual 6293 - Precision Water Level Instruments Issue 2.1
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2.2 Features
Most wiring connections to the 6541B Water Level Instrument are made by the
front panel screw terminals.
Power Supply. The instrument can be powered either from a Unidata battery pack
plug or, via flying leads from an external power source.
HSIO.
Access to a 4 wire plus ground Unidata HSIO interface is provided
by the front panel terminals. A “data in” terminal allows extension
of a HSIO instrument chain.
SDI-12.
These terminals provide a connection point for the Version 1.3
compliant SDI-12 interface.
Current Loop. The 4-20mA current loop is a 3 wire optically isolated interface. It
requires that the loop power be supplied by the logger end of the
loop. Note: The base level 6541B instrument is not fitted with the
current loop interface.
