Gantner e.bloxx A5CR, Руководство пользователя

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e.bloxx A5-1CR
MEASUREMENTS
22
HB_EBLOXX-A5CR_E_V11.doc
Gantner Instruments Test & Measurement GMBH
The e.bloxx support sensor measurements in 4-wire technique. Especially 4-wire technique compensates the influence
of non-symmetric cable resistances. To avoid self heading effects of the Cryo sensor the sensor excitation is a switched
current with an max. amplitude of 16
µ
A. The effective current using 1 sensor is 8
µ
A, using 2 sensors it is 5,3
µ
A. The
resistive measuring range is 0 to 6500
Ω
. Usually Cryo sensors have a working range between 5000
Ω
at the lower
temperature (e.g.3 Kelvin) and about 60
Ω
at the higher temperature (e.g. 300 Kelvin). So the power consumption of the
sensor at low temperatures is approx. 50 nW. The individual non-linear characteristic of the Cryo sensors could be
compensated by importing a set of sensor data e.g. as txt or csv file into the module e.bloxx A5CR.
4.3. Digital Output - Status
Picture 4.7. – Digital Output used as Status Output
Picture 4.8. - Signal Diagram of Status Output
The digital output can be used to output
host-controlled
or
process-controlled
status signals.
With the host-controlled digital status output, the digital output is set according to the status information received by the
e.bloxx via bus.
With the process-controlled output of status information the e.bloxx monitors measured values, resp. sensor variables
as to certain threshold values. The digital output is set if one or several threshold conditions are fulfilled. The user via
the Configuration Software ICP 100 can freely define the threshold values. The user can also preset the logical signal
level.
The distribution voltage can amount from 10 up to 30 VDC. It has to be supplied externally or picked up by the power
supply of the e.bloxx.
The status of the digital output can be scanned as 1/0 information via bus.