Measurement Computing Switch & Sense 8/8 User Manual page 14

Switch & Sense 8/8 User's Guide
Extending the input range
You can extend the input range beyond the 5 to 30 V specified by adding an external resistor. Figure 9 shows
the external resistor (R
The equation R = 100 * (V
ext
Make sure the external resistor is capable of handling the power generated by the input. Calculate the power
requirement in watts (P
V
in
R
P
).
ext
– 30) calculates the resistor value for a given V
in
) using the equation P
w w
R 1.6 K
ext
= 100 * (V – 30)
ext in
= R /10000
w ext
Figure 9. External resistor added to extend input range
= R /10000.
ext
14
Functional Details
.
in