Alnor 9870, Owner'S Manual

7 

This number represents the approximate percentage 
of battery life remaining, and will range from less 
than 0% for a low battery to something over 100% 
for a short time while the “surface charge” of the 
new batteries burns off. 

After 5 seconds the meter will begin to display 
velocity or temperature in the selected units. Units 
available for display are standard feet per minute (S 
fpm) and degrees Fahrenheit (°F), and standard 
meters per second (S m/s) and degrees Celsius (°C), 
depending on which instrument you purchased. The 
units of measure cannot be changed in the field. 
 

Selecting temperature/velocity display 

The 

TEMP/VEL

 switch on the instrument allows 

you to switch between the instrument’s two 
measuring modes. Slide the switch to the 

TEMP

position to read the current temperature, or to the 

VEL

 position to read the current velocity. 

Selecting the sensor response 

The Model 9870 has a 

FAST/SLOW

 response 

switch for setting the sensor response speed. In the 
slow response mode, it displays the average 
velocity measured during the past 12 seconds. This 
is a running average, so the display is updated once 
a second. In the fast response mode, the meter 
displays the average velocity measured during the