HT instruments HT157 - Manual (Page 32)

HT155 - HT157
EN - 30
5.2.3. ANALYSIS IN THIRD-OCTAVE BAND (1/3)
5.2.3.1. Operations for sections LIST, GRAPH
1. Select the “List” icon and confirm with “ ”. The instrument displays the following
numerical screen:
 Line 1
 Line 2
 Lines 3,8
 Line 9
Fig. 29: Numerical screen of analysis in third-octave band (1/3)
Line 1
The left part shows the current date/time set on the instrument, while the
right part shows the measuring range selected.
 Date/time setting
8. Use the “ ” and “
” keys to move the flashing cursor to fields YYYY
(year), MM (month), DD (day), HH (hours), MM (minutes) SS
(seconds)
9. Use the “ ” and “ ” keys to select the desired program:
 Configuration of the measuring range
1. Use the “ ” and “
” keys to move the flashing cursor to symbol “R”
2. Use the “ ” and “ ” keys to select the measuring range among the
following options: 0
90dB, 10 100dB, 20 110dB, 30 120dB, 40
130dB, 50 140dB according to the reading carried out by the
instrument. After each modification, the reading takes approximately
3s to become stable
Line 2
In this line, by using the “ ” and “ ” keys, it is possible to select the
type of frequency weighting (A, C or Z) and the three pages (0, 1 and 2)
of the instant values of the sound pressure levels for each central band
frequency from 12.5Hz to 16kHz
Lines 3-8
These lines show the instant values of the sound pressure level for each
central band frequency from 12.5Hz to 160 Hz (page 0), from 200Hz to
2.5kHz (page 1) and from 3.15kHz to 16kHz (page 2), further to the
values of the parameters LA, LC, LZ with A, C and Z weighting (page 2)