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sensor output
sensor output
v
c
o
c v o
5.5 How to provide a power supply to the sensors
Each voltage/current channel has its own connections to allow sensors to
be supplied with power at 5V DC or 9V DC. By default, the voltage will be
at approximately 9V DC. The exact voltage will depend on the state of the
internal batteries or the voltage of the external power supply, if present.
Some models have the option to change the sensor power to 5V DC
(±0.1%). This is dealt with in section 4.10.4. The maximum total current
available is 50 mA. Section 4.10.4 describes the logger setup procedure
to switch power to the sensors prior to measurement. The following
diagram shows how to connect the sensor to the switched sensor power
supply: -
power to sensor
power to sensor
o
c
v
v
c
o
