HT instruments HT157 - Manual (Page 35)

HT155 - HT157
EN - 33
5.2.3.2. Operations in TOTAL section
1. Select the “Total” item in the main menu (see Fig. 22) and confirm with “ ”. The
instrument displays the following screen, relevant to the “Linst” item:
Fig. 32: Total section screen 1/3 spectrum analysis – Instant values
2. The initial part shows the system date/time and the measuring range which can be
modified by using the “ ” or “ ” keys. In the five central lines, the instrument
provides the instant values of the following sound pressure levels in frequency
weightings A, C, Z and with time constants Fast, Slow, Impulse: LAFp, LCFp, LZFp,
LASp, LCSp, LZSp, LAIp, LCIp, LZIp. Lines 7 and 8 show, in graphic bars, the instant
values of the quantities: LAFinst, LASinst, LAIinst, LCFinst, LCSinst, LCIinst,
LZFinst, LZSinst, LZIinst
3. Select the “ ” icon and confirm with “ ” to save the data in the instrument’s
memory
CAUTION
The “Max” and “Lock” functions are not active for instant values shown in the
graphic bar
4. With flashing cursor on the “Linst” item, select the “Leq1s” options with the “
” or
“ ” keys. The instrument shows the following screen relevant to the values of the
noise level equivalent to 1s
Fig. 33: Total section screen 1/3 spectrum analysis – Leq1s values