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HT155 - HT157
EN - 4
2. GENERAL DESCRIPTION
This manual refers to models HT155 and HT157. In the manual, the generic term
“instrument” refers to both devices and, if not otherwise indicated, characteristics are to be
considered as common to both models
The instrument has the following functions:
Measurement of sound pressure level (SPL) Type 1
Real-time and statistic analysis
Octave band and in 1/3 octave band analysis (HT157 only)
Measures weighted in frequency by means of A, C and Z curves and F, S impulses
Fast, Slow, Impulse, PeakC+, Peak C- integrations
Measurement of noise equivalent levels (Leq)
Inner memory for saving measures and recordings
AC analogue output for connection to external dataloggers
USB interface for connection to PC and/or USB pen drive
Wide backlit LCD display
The front panel of the instrument bears the function keys for the selection of the above-
listed functions (see chapter 4.2). The measured value appears on the wide LCD display
with the indication of the measuring unit and of the enabled functions.
In the lower part of the instrument there are the terminals for the AC analogue output with
3,5 mm coaxial connector and the (USB) ports for the connection of a possible DC 5V
external adapter for power supply without using the internal battery and RS-232 (non-
active output)
In the rear part of the instrument there is a hole for installing the instrument onto a possible
tripod while measuring.
Summary of Contents for HT155
Page 1: ... Copyright HT ITALIA 2011 Release EN 1 02 28 12 2011 HT155 HT157 User manual ...
Page 2: ......
Page 62: ...HT155 HT157 EN 60 12 APPENDIXES 12 1 APPENDIX 1 FREQUENCY WEIGHTING CHARACTERISTICS ...
Page 63: ...HT155 HT157 EN 61 12 2 APPENDIX 2 CHARACTERISTICS OF 1 3 OCTAVE BAND FILTER ...
Page 64: ...HT155 HT157 EN 62 ...
Page 65: ...HT155 HT157 EN 63 ...
Page 67: ...HT155 HT157 EN 65 12 4 APPENDIX 4 CHARACTERISTICS OF 4HZ HIGH PASS DIGITAL FILTER ...