Hello,
On an automation assignment we have to simulate a PT100 temperature sensor with a potentiometer. First problem is that these potmeters are overly expensive compared to standard values like 100 Ohm, 1K ohm etc. We need about 20 Ohm. If we wire a standard value, say 100 Ohm in paralell with a lower value fixed resistor we obtain the right values, but the increase per turn is now logarithmic.
Is there a clever way of solving this without buying the expensive potentiometers? We need linear increase in resistance because our front panel will not look good for presentation with a logarithmic scale.
As always, I am very thankful for your advice.
On an automation assignment we have to simulate a PT100 temperature sensor with a potentiometer. First problem is that these potmeters are overly expensive compared to standard values like 100 Ohm, 1K ohm etc. We need about 20 Ohm. If we wire a standard value, say 100 Ohm in paralell with a lower value fixed resistor we obtain the right values, but the increase per turn is now logarithmic.
Is there a clever way of solving this without buying the expensive potentiometers? We need linear increase in resistance because our front panel will not look good for presentation with a logarithmic scale.
As always, I am very thankful for your advice.