
UNIDATA
Unidata Manual 6293 - Precision Water Level Instruments Issue 2.1
4
2.3 Operating
Modes
The operating modes of the 6541B WLI are set using the 8 DIP switches on the
front panel.
Switch Function
Off
On
1
DIR (Pulley Dir.)
Clockwise
Counter Clockwise
2
PULLEY (Metric Pulleys)
1
500mm / 1ft pulley 100mm pulley
3
UNITS (of measurement)
mm
Feet x.xx
4
FSD (Full Scale Deflection) Max. Count
2
65535 299999
5
MODE SDI-12
Future
option
8
POWER
Instrument Off
Instrument On
Note 1: The current loop interface will only work with a maximum count setting of 65535. The
299999 (4 FSD) setting cannot be used for HSIO please use 5 SDI-12 instead.
Note 2:
Pulley size & resolution
Pulley Circumference Resolution
100mm 0.1mm
500mm 1mm
1 foot
0.01’
In general there are three ways of using the 6541...
With no data logger -
As a water level measurement and display instrument the water level can be
observed on the LCD display but measurements are not stored.
With an Internal Data Logger -
As a water level measurement and display instrument with a built-in data logger –
the 6541-nnn/C that can measure up to three additional external parameters.
With an External Data Logger -
As a water level measurement and display instrument, with an external data
acquisition facility such as a UNIDATA STARLOGGER. This is required when
you need to measure many external parameters.