GP-HR Temperature
Application Notes
Any combination of the three analogue inputs of the GP-HR Logger can be configured to read Temperature. Different circuits and logger setup are required for Thermister and PT1000 sensors.
Thermister
Application Notes
For thermister applications an excitation resister is
required between the input line and the switched supply line. For a 10k ohm thermister
(Beta 3892 Farnell Part no 151-591 or 732-242) the excitation resister must have a value
of 15k ohms and an error of 0.1% or less . The channels must then be setup to Thermister
temperature mode using the OmniLog Software. 1, 2 and 3 Thermister Temperature Probe sets
are supplied as standard probe sets for the GP-HR. These have the correct excitation
resisters fitted inside the adapter socket.
Circuit for GP-HR with 3 Thermister Temperature inputs
R1, R2 and R3 are 15k ohm ± 0.1% for a 10k ohm thermister
Setting up Thermister channels
using the OmniLog Software
Connect the GP-HR logger to a computer and Run the OmniLog
software
From the Logger
Control Screen select Channel and Probe Setup
Select the Channel that you wish to setup (Ch 1, 2 or 3)
From the Probe box select the Temperature
(Thermister) option as shown
Notice that after the Temperature (Thermister) probe has
been chosen the Units in the Unit
and Scaling box has been set to ° C
Now give the Channel a meaningful Long and Short name in the Logger
Channel Name box as shown below
Click on the Write Unit, Scaling and Calibration values to the Logger button to send the new settings to the logger.
If you have use high accuracy thermisters no calibration
will be required.
PT1000
Application Notes
For PT1000 applications an excitation resister is required
between the input line and the switched supply line. The excitation resister must have a
value of 3k3 ohms and an error of 0.1% or less . Farnell Part no 433-093 or 339-672).
Filter capacitors are required between the inputs and the common line. The channels must
then be set to PT1000 mode using the OmniLog Software.
Circuit for GP-HR with 3 PT1000 Temperature inputs
R1, R2 and R3 are 3k3 ohm ± 0.1%
Filter Capacitors are 0.1uF
Setting up PT1000 channels using
the OmniLog Software
Connect the GP-HR logger to a computer and Run the OmniLog
software
From the Logger
Control Screen select Channel and Probe Setup
Select the Channel that you wish to setup (Ch 1, 2 or 3)
From the Probe box select the PT1000
(Unamplified) option as shown
Notice that after the PT1000 (Unamplified) probe has been
chosen the Units in the Unit
and Scaling box has been set to ° C
Now give the Channel a meaningful Long and Short name in the Logger
Channel Name box as shown.
Click on the Write Unit, Scaling and Calibration values to the Logger button to send the new settings to the logger.
