GP-HR Switch Input
Application Notes
Any combination of the three analogue inputs of the GP-HR Logger can be configured to read switches. Either DPST or SPST
switches can be used. A SPST switch will require a pull
up resistor for proper operation on the GP-HR Logger.
DPST Switch Input Circuit
No additional components are required
SPST Switch Input Circuit
A pull up resistor is required for proper operation of this
circuit.
The value of the pull up resistor is dependent on the
length of cable between the switch and the logger. We recommend 1M ohm if the switch is 10
metres or less from the logger and 200 K ohms if the switch is 100m from the logger. If
the switch is being used with a long cable in an electrically noisy environment an RC
filter network across the switch may be required.
R1 = 200 K Ohms to 1M Ohm depending on distance from switch
to logger
Setting up a Switch Input channel
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 Channel 1 to 3 (These are the analog input channels)
From the Probe box select the Switch option as shown
Notice that after the Switch probe has been chosen the Units in the Unit and
Scaling box has been set to switch
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.
