User manual

Toolbox 32 User Manual 1.47d www.cse-semaphore.com/mykingfisher
Page
226
Example Calibration
The IO-4 is to be calibrated for a strain gauge input used to measure the water level in a tank. Note: the tank
must be full to allow the IO-4 to be calibrated.
• Select the Reset Ch.01 button.
• Select the Enable Ch.01 button.
• For the first input, lift the strain gauge out of the water (this will probably produce a voltage of about 1mV
into the IO-4).
• Select Set Ch.01 Min.
• Put the strain gauge back into the full tank (this may produce a voltage of say 48mV into the IO-4. The
actual voltage will depend on the calibration of the strain gauge).
• Select Set Ch.01 Max. The IO-4 is now calibrated.
IO-4 Strain Gauge Test Input
Sometimes it is useful to manually set the strain gauge voltage input and this can be done by using a 0-
50mV voltage source as shown below.
2.55K
2.55K
5K Trimpot
53
Ohms
+E (+5V)
+S
-S
-E (0V)
IO-4 Terminal
Block
1
4
3
2
Figure: Circuit for a 0-50mV Strain Gauge Test Device