How do I create a voltage divider?

For input voltage to the logger greater than 2.5 volts DC, you will need to make a voltage divider.
A voltage divider will drop the voltage of the input signal to the level the logger can measure.
First determine the needed attenuation ratio; divide the input volts by the output volts to the logger:
A = input volts/2.5

If the maximum signal is 5 volts DC, and you wish to use the HOBO's full scale range of 2.5 volts
DC, the attenuation is 2:1, or just 2. Once you have determined the attenuation (A), you can calculate for the
Resistor (R1). For now, pick a value for R2 (typically 10k), then calculate for R1.
R1 = (A - 1) *R2

From the above example A = 2 and, if you picked a value of 10,000 for
R2:
R1 = (2 - 1) *10,000
R1 = 10,000 ohms
Therefore, R1 and R2 are both 10K resistors.

There are a few practical considerations. If the sum of R1 and R2 is too low (Rmin), you
could overload your input source or heat up the resistors. If the sum of R1 and R2 is too high
(Rmax), it could be a poor match for our volt logger's 10K input impedence. Also, resistors do
not come in every possible resistance value. You will have to plug in available resistance values
until you reach a voltage divider that is both accurate enough and keeps the sum of R1 and R2 within practical limits.