Vaisala PTU300 - Manual (Page 67)

Chapter 4 _________________________________________________________________ Operation
VAISALA ________________________________________________________________________ 65
CHAPTER 4
OPERATION
This chapter contains information that is needed to operate this product.
Getting Started
Within a few seconds after power-up the led on the cover of the
transmitter is lit continuously indicating normal operation. If the data
logger module is installed, the startup may take up to 18 seconds. When
using the optional display and turning the transmitter on the first time, the
language selection menu window opens. Select the language with the
▼▲ arrow buttons and press the SELECT button (the left-hand
button).
The pressure has an effect on humidity calculations and accuracy.
Therefore, accurate calculations can be achieved only when the ambient
pressure is taken into consideration. PTU300 uses measured pressure for
compensation by default.
See section Pressure Compensation Settings on page 109 for instructions
on how to set the pressure.