Larson Davis SoundAdvisor 831C User manual

Larson Davis
SoundAdvisor
Model 831C
Sound Level Meter
Reference Manual

SoundAdvisor Model 831C i-2
Copyright
Copyright 2021, by PCB Piezotronics, Inc. This manual is copyrighted, with all rights reserved. The manual may not be copied
in whole or in part for any use without prior written consent of PCB Piezotronics, Inc.
Disclaimer
The following paragraph does not apply in any state or country where such statements are not agreeable with local law:
Even though PCB Piezotronics, Inc. has reviewed its documentation, PCB Piezotronics Inc. makes no warranty or
representation, either expressed or implied, with respect to this instrument and documentation, its quality, performance,
merchantability, or fitness for a particular purpose. This documentation is subject to change without notice, and should not be
construed as a commitment or representation by PCB Piezotronics, Inc.
This publication may contain inaccuracies or typographical errors. PCB Piezotronics, Inc. will periodically update the material
for inclusion in new editions. Changes and improvements to the information described in this manual may be made at any
time.
Safety
If the equipment is used in a manner not specified by Larson Davis, the protection provided by the equipment may be
impaired.
Recycling
PCB Piezotronics, Inc. is an environmentally friendly organization and encourages our customers to be
environmentally conscious. When this product reaches its end of life, please recycle the product through a local
recycling center or return the product to:
PCB Piezotronics, Inc.
Attn: Recycling Coordinator
1681 West 820 North
Provo, Utah, USA 84601-1341
Warranty
For warranty information, go to the Larson Davis Product Warranty page.
Contact Larson Davis
Website
www.larsondavis.com
Worldwide Corporate Headquarters
Larson Davis - a PCB Piezotronics division
3425 Walden Avenue
Depew, NY 14043-2495 USA
Toll-free (in the US): 888-258-3222
Phone: [phone]
USA fax: [phone]
E-mail: [e-mail]

I831C.01 Rev O- Firmware Version 4.6 ii-1
Table of Contents
Module 1 Model 831C Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Applications and Basic Operations
1.2 Hardware Features
1.3 Performance Features
1.4 Standard 831C Package Contents
1.5 Available Options and Accessories
Module 2 Instrument Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1 Assembling Your 831C SLM
2.2 Powering the 831C SLM
2.3 Instrument Hardware Overview
2.4 Display Elements Overview
Module 3 Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.1 Operating the 831C Using the Meter Display
3.2 Operating the 831C Remotely
3.3 Setting File Storage Preferences
Module 4 Using the Data Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.1 SoundAdvisor 831C Display In SLM Mode
4.2 Enabling or Disabling Display Tabs
4.3 831C Display in FFT Mode
Module 5 Calibrating Your SoundAdvisor 831C . . . . . . . . . . . . . . . . . . . . . 48
5.1 Understanding Calibration Values
5.2 Choosing a Calibrator
5.3 Reviewing the Calibration Settings
5.4 Calibrating Your SoundAdvisor 831C
Module 6 Creating a Measurement Setup . . . . . . . . . . . . . . . . . . . . . . . . . . 54
6.1 831C Setup Manager Overview
6.2 Creating a Custom Setup File On the Meter
6.3 Troubleshooting a Measurement Setup File
Module 7 Making a Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
7.1 Before You Start
7.2 Performing the Measurement
7.3 Storing the Measurement
Module 8 Managing Measurement Data Files . . . . . . . . . . . . . . . . . . . . . . . 74
8.1 Setting Data File Storage Preferences
8.2 Using the File Manager
8.3 Saving, Moving, or Copying Data Files
Module 9 Setting System Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
9.1 Setting Instrument Identification
9.2 Updating the Meter Time
9.3 Using NTP to Sync the Meter Clock
9.4 Editing Power Settings
9.5 Setting Meter Preferences
9.6 Setting Localization Options
9.7 Setting Active/Hidden Pages On the Displays Tab
9.8 Enabling or Disabling Options
9.9 Setting Network Preferences

SoundAdvisor Model 831C ii-2
9.10 Configuring an Email Server On the Meter
9.11 Enabling or Disabling Cloud Storage
9.12 Utilizing the Logic In or Logic Out Feature
9.13 Choosing Preamp Heater Options
9.14 Setting Reference Spectra
9.15 Generating an App Password
Module 10 System Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Module 11 Managing 831C Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
11.1 Using the Meter Lock
11.2 Using Network Security
Module 12 Using System Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
12.1 Troubleshooting a Bad Flash Block Error
Module 13 831C Network and Connections . . . . . . . . . . . . . . . . . . . . . . . . . 104
13.1 Configuring 831C Network Connections
13.2 Setting Up the Meter’s Network ID
13.3 Using WiFi On Your 831C
13.4 Disconnecting a Cloud Storage Dropbox Account
Module 14 Software, Firmware, and Options . . . . . . . . . . . . . . . . . . . . . . . . 109
14.1 Updating the G4 LD Utility
14.2 Upgrading 831C Firmware by Using G4 LD Utility
14.3 Upgrading Meter Firmware Options
14.4 Enabling or Disabling Optional Firmware
Module 15 Using Measurement History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
15.1 Setting Up a Measurement With Measurement History
15.2 Viewing Measurement History Data Files
Module 16 Using Time History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
16.1 Setting Up a Measurement With Time History
16.2 Making a Time History Measurement With Sound Markers
16.3 Viewing Time History Data
Module 17 Using Event History Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
17.1 Setting Up the Event History Measurement
17.2 Storing Event Data
17.3 Viewing Event History Data on the Events Tab
17.4 Setting Advanced Event Triggers
17.5 Understanding Level and Dynamic Triggering
Module 18 FFT & Tonality Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
18.1 Preparing the Equipment
18.2 Creating an FFT Setup File On the Meter
18.3 Making the FFT Measurement
18.4 Viewing FFT Data Files On the Meter
Module 19 Using 831C Sound Recording . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
19.1 Setting Up Markers for Sound Recording
19.2 Making a Manual Sound Recording Using Mark Sound Type
19.3 Making an Automated Event Sound Recording
19.4 Enabling Measurement History Sound Recording
19.5 Understanding Recording Settings and Sound Quality
19.6 Sound Recording Playback

SoundAdvisor Model 831C ii-3
Appendix A Technical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.1 Instrument Platform Specifications
A.2 Model PRM831
A.3 Base Software
A.4 Octave Band Analysis Software – Option 831C-OB3
A.5 Event Logging Software (Option 831C-ELA)
A.6 Time History Software (Option 831C-LOG)
A.7 FFT Analysis Software Specifications (Option 831C-FFT)
A.8 PTB Approved Firmware
A.9 Frequency Response
A.10 Declaration of Conformity
Appendix B Measuring Sound Using IEC 61672-1 . . . . . . . . . . . . . . . . . . . . . . B-1
B.1 Overview
B.2 IEC 61672-1 Section 9.3
Appendix C Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

SoundAdvisor Model 831C 1
Module 1 Model 831C Features
The SoundAdvisor Model 831C SLM is a Class 1 acoustic monitoring
instrument with a full-color touchscreen that measures noise frequency,
sound pressure level, and community and environmental sound. The “C” in
831C refers to the full-color screen.
G4 LD Utility software (G4) connects your meter to your PC via USB, WiFi, or
TCP/IP. With G4 you can calibrate the meter, create setup files, download
measurements, and analyze the results.
1.1 Applications and Basic Operations ....................................................................................... 2
1.2 Hardware Features ................................................................................................................. 2
1.3 Performance Features ............................................................................................................ 3
1.4 Standard 831C Package Contents .........................................................................................3
1.4.1 About Serial Numbers
1.5 Available Options and Accessories ........................................................................................5
1.5.1 Firmware Options
1.5.2 Hardware Options
1

SoundAdvisor Model 831C Applications and Basic Operations 2
1.1 Applications and Basic Operations
The 831C monitors:
• City noise
• Construction noise
• Airport noise
• Nuisance noise
• Noise ordinance compliance
• Wind farm noise
The 831C performs the following operations:
TRY THIS Explore the interface,
press buttons, change settings,
and test the operations.
• Measure sound using run, stop, pause, and resume measurement
• Display broadband and spectral sound values on a full-color display
screen
• View live and stored data while a measurement is in process
• Log simultaneously to time, statistical measurement, and event
histories
• Use markers to annotate portions of time histories, including voice
annotation
• Automatically back up data to prevent data loss on power failure
• Calibrate using a Precision Acoustic Calibrator, and store calibration
history
• Time-stamping for Lmax, Lmin, Lpeak-(max) single event metrics.
• Sync clock with PC, attached GPS, or Network Time Protocol (NTP)
• Create multiple Setup configurations using the Setup Manager
• Stream and record audio continuously or for events using sample
rates up to 51.2 ksps in compressed or uncompressed format
• Communicate via USB, Ethernet, WiFi, or cellular (with cellular
gateway)
• Operate completely from the device itself, or remotely using G4 LD
Utility software
• Easily expand memory using USB memory
• Select desired color theme on the full-color graphic LCD display with
touchscreen user interface
1.2 Hardware Features
The 831C is a precision-integrating sound level meter with the following
hardware features:
TAKE NOTE Up to 32GB USB
memory can be purchased from
Larson Davis as an option.
• 2 GB internal industrial grade data memory
• 240 x 320 full-color graphic LCD display with touchscreen user
interface

SoundAdvisor Model 831C Performance Features 3
• Quiet Touch elastomeric keypad
• Meter uses NiMH, photo-lithium, lithium-Ion, and alkaline cells; 4-AA
batteries provide upwards of 8 hours operating time
• AC/DC output jack with full dynamic range option
• Compatible with 61 m (200 ft.) microphone extension cable (full scale
to 20 kHz)
• Dust-resistant, durable plastic case with lanyard (tripod mount is also
available)
• USB 2.0 high-speed host connector for mass storage, weather sensors,
USB headset, and WiFi communication devices
• USB 2.0 high-speed peripheral connector for control and data
download by a PC
• I/O connector for power, weather transducers, logic input/output, and
preamplifier communications
1.3 Performance Features
• Large dynamic range, > 120 dBA
• RMS Detectors: Slow, Fast, Impulse
• RMS Frequency Weighting: A, C, Z
• Peak Frequency Weighting: A, C, Z
• Any LevelTM Simultaneous measurement and display of Max and Min
sound pressure levels (Slow, Fast, and Impulse detectors), plus Leq
and Peak levels, all with A, C and Z frequency weighting
• Weather Measurements (Wind Speed and Direction, Temperature, and
Humidity with SEN03x)
• SLM and FFT modes
• Multiple language support: English, French, Italian, German, Spanish,
and Chinese
• Field-upgradeable firmware
1.4 Standard 831C Package Contents
The 831C is available as part of a specialized system or in a standard
configuration. The following accessories come with the standard
configuration:
TAKE NOTE Report any damage or shortage immediately to Larson Davis/PCB
Piezotronics, Inc. See the back cover of this manual for contact information.

SoundAdvisor Model 831C Standard 831C Package Contents 4
The 831C is shipped in protective packaging. First, verify the shipment
contains all parts and accessories for the configuration you selected. Retain
the packaging for safe shipment for calibration service.
Table 1.1 SoundAdvisor 831C Standard Package
Accessory Type Available Items
SoundAdvisor 831C
Microphones
(377B02) ½-inch free-field
prepolarized microphone, 50 mV/
Pa, providing performance
conforming to Class 1 sound level
meter standards
(377C20) ½-inch random incidence
prepolarized microphone, 50 mV/
Pa, providing performance
conforming to Class 1 sound level
meter standards
Note: You can use other microphones with the 831C. For more information,
see 1.5.2 Hardware Options.
Microphone
Preamplifiers
PRM831 PRM2103
CAUTION: Sensitive to
static electricity
CAUTION: Sensitive to
static electricity

SoundAdvisor Model 831C Available Options and Accessories 5
1.4.1 About Serial Numbers
The 831C serial number is printed on the back panel label. The microphone
model and serial numbers are engraved on the outside of the microphone.
The preamplifier model and serial numbers are engraved on the outside
surface of the preamplifier.
We recommend that you record the purchase date, model and serial numbers
for your instrument, preamplifier, and microphone.
1.5 Available Options and Accessories
In this section:
•1.5.1 Firmware Options
•1.5.2 Hardware Options
Accessory Kit
(831-ACC) includes
these items:
(831-CCS) Hard Shell Case
(CBL138) USB to mini-B cable, 1.8 m
4 Rechargeable AA NiMH batteries
(PSA029) Universal AC USB Power
Adapter
(WS001) 3 ½-inch windscreen
USB Drive
Includes:
• G4 LD Utility software
• 831C Reference Manual
• Digital Calibration Certificates
Lanyard
Table 1.1 SoundAdvisor 831C Standard Package
Accessory Type Available Items

SoundAdvisor Model 831C Available Options and Accessories 6
1.5.1 Firmware Options
LEARN MORE To purchase these
options, see “Contact Larson
Davis” on page ii-2.
The following upgrades/options are available to purchase from Larson Davis.
831C-LOG
Time History data logging with periods from 2.5 ms to 24 hours.
831C-OB3
Real-time 1/1 & 1/3 Octave Frequency Analysis.
831C-ELA
Measurement History for the manual or timed storage of statistical data, and
exceedance-based Logging Analysis with Events.
831C-SR
Make event based and manual sound recordings in WAV or OGG format that
can be sent via email or SMS and stored in the measurement data.
831C-MSR
Measurement History for the manual or timed storage of statistical data with
all sound recording capabilities.
831C-SW
Make direct USB communication with Sierra Wireless RV50X cellular gateway.
831C-AUD
Using the AudCal software from Larson Davis in conjunction with your
SoundAdvisor 831C enables you to test the calibration of audiometers and
sound booths.
831C-SCH
Scheduling feature for G4 LD Utility.
1.5.2 Hardware Options
The following table contains only a few examples of the hardware accessories
available for your 831C. Additional components include, but are not limited
to, microphones, preamplifiers, software, power supplies, tripods, calibrators,
sensors, protective cases, adapters, and cables. For a complete listing of
standard and system accessories, see the SoundAdvisor Ordering page at
Larson Davis.com.

SoundAdvisor Model 831C Available Options and Accessories 7
Table 1.2
Accessory Type Available Options
Microphone Options
Note: These mics are available
directly from Larson Davis. You
can also use other
microphones with the 831C.
(377A15) 1-inch, prepolarized
pressure condenser microphone,
50 mV/Pa, providing performance
conforming to Class 1 sound level
meter standards
(377B01) ¼-inch free-field
prepolarized microphone, 50 mV/
Pa, providing performance
conforming to Class 1 sound level
meter standards
(377B10) ¼-inch free-field
prepolarized microphone, 50 mV/
Pa, providing performance
conforming to Class 1 sound level
meter standards
(377C01) ¼-inch free-field
prepolarized microphone, 50 mV/
Pa, providing performance
conforming to Class 1 sound level
meter standards
(377C13) ½-inch, prepolarized,
pressure condenser microphone,
50 mV/Pa, providing performance
conforming to Class 1 sound level
meter standards
(377C10) ¼-inch free-field
prepolarized microphone, 50 mV/
Pa, providing performance
conforming to Class 1 sound level
meter standards
Microphone Preamplifier
Options
(426E01) ½-inch ICP Low Noise
microphone preamplifier
(requires adapter ADP074)
(PRM2103) Outdoor microphone
preamplifier
Environmental Protection
Options
(EPS2116) Environmental Shell
Protects microphone and preamplifier from rain and wind with
mounting options for pipes, poles, and most tripods
(EPS030-831)
Weather-proof enclosure for remote noise monitoring; includes battery
(NMS/EPS044)
Solar-powered noise monitoring system for outdoor, long-term, and
unattended sound monitoring
(NMS/EPS045)
Permanently-installed, solar-powered noise monitoring system for
outdoor, long-term, and unattended sound monitoring
Weather Data Acquisition
Options
(SEN031) combined weather sensor, wind speed and direction (with no
moving parts), temperature, humidity, pressure, and rainfall (requires
CBL167 or CBL229 and DVX008A)
(SEN032) Ultrasonic Anemometer: wind speed and direction only
sensor (requires CBL167 or CBL229 and DVX008A)
Communication Options
(DVX012, 013, 014, 015, 008A) (831-INT-ET) with integrated
Ethernet capability
GPS Options (GPS001) GPS Receiver, USB Magnetic Mount

SoundAdvisor Model 831C Available Options and Accessories 8
Equivalent Electrical
Impedance Adapter Options
Choose one of the following
adapters in place of the
microphone when making very
high impedance
measurements. The adapter
acts as a series capacitor with
the same capacitance as the
microphone it replaces. If
you’re making a square wave
pulse measurement, include a
100 kHz, low pass, T filter with
the adapter.
(ADP002) 6.8pF BNC Input Adapter for ¼-inch,
7 pF microphone equivalent
(ADP090) 12 pF, BNC Input Adapter for ½-inch,
12 pF microphone equivalent
(ADP092) BNC In-Line, Low Pass Filter, 75kHz
Table 1.3
Cables: Extension and Interface Cables
Microphone Extension Cable: EXCXXX (shielded), where XXX is the
length in feet (XXX = 010, 020, 050, 100, and 200 available)
CBL138 USB Cable
CBL139 AC/DC Output Cable CBL170 I/O Interface Cable
Table 1.2
Accessory Type Available Options

SoundAdvisor Model 831C Assembling Your 831C SLM 9
Module 2 Instrument Overview
This module describes the hardware and display components that make
the SoundAdvisor Model 831C the best meter for monitoring sound.
In this module:
2.1 Assembling Your 831C SLM ....................................................................................................9
2.1.1 Connecting the Microphone and Preamplifier
2.1.2 Connecting the Preamplifier to Meter
2.1.3 Disconnecting the Preamplifier
2.1.4 Preparing the 831C for Long Term Storage
2.2 Powering the 831C SLM ........................................................................................................ 11
2.2.1 Using Battery Power
2.2.2 Using External Power
2.2.3 Understanding 831C Power Events and Indications
2.2.4 Powering On or Off
2.2.5 Using the Power Control Page
2.3 Instrument Hardware Overview .......................................................................................... 16
2.3.1 Using 831C Buttons
2.4 Display Elements Overview .................................................................................................. 19
2.4.1 Changing Display Color Themes
2.4.2 Using Tabs and Pages
2.4.3 About Status Bar Icons and Indicators
2.4.4 Main Menu Overview
2.4.5 Tools Menu Overview
2.4.6 Power Control Menu Overview
2.1 Assembling Your 831C SLM
In this section:
•2.1.1 Connecting the Microphone and Preamplifier
•2.1.2 Connecting the Preamplifier to Meter
•2.1.3 Disconnecting the Preamplifier
•2.1.4 Preparing the 831C for Long Term Storage
2.1.1 Connecting the Microphone and Preamplifier
CAUTION DO NOT handle the microphone and preamplifier without
observing the following items:
• Ground yourself so the pogo pin is not exposed to static
shock.
• Never use excessive force.
2

SoundAdvisor Model 831C Assembling Your 831C SLM 10
• Gripping tightly or screwing tightly is unnecessary.
• Do not remove the microphone grid cap and expose the diaphragm.
FIGURE 2-1 Microphone and Preamplifier PRM831
The bottom of the microphone attaches to the top of the
preamplifier. The preamplifier body houses a single gold pin with
threads on the top edge, which are designed to fit the 1/2-inch
microphone.
CAUTION Do not allow dust or debris to collect in an unassem-
bled preamplifier.
Step 1. Carefully place the bottom of the microphone over the top of the preamplifier
and gently screw the assembly together. The microphone body should seat
smoothly against the preamplifier body.
To disconnect the microphone:
• Lightly grip the 2 engraved lines on the microphone body and gently turn.
2.1.2 Connecting the Preamplifier to Meter
CAUTION Do not attempt to screw the preamplifier onto the 831C
Step 1. Both the preamplifier and the preamplifier housing on the meter are marked for
correct alignment; look for a vertical, engraved line on the preamplifier, which
aligns with the arrow about the button on the 831C. For reference, see Figure 2-2 .
Step 2. With the alignment marks on both pieces lined up vertically, insert the 5-pin
connector at the bottom of the preamplifier snugly into the top of the 831C until
you hear a small click.
2.1.3 Disconnecting the Preamplifier
Step 1. To disconnect the preamplifier, press and hold this button while gently pulling
the microphone/preamplifier assembly from the meter.
FIGURE 2-2 831C Preamplifier Housing

SoundAdvisor Model 831C Powering the 831C SLM 11
2.1.4 Preparing the 831C for Long Term Storage
The Hardware Power Switch on the bottom of the 831C disconnects the batteries from the
831C hardware. (For reference, see Figure 2-6.) The real-time clock maintains its value
while the switch is off. The power switch prevents battery drain when the meter is not in
use for an extended period of time. If you plan to store the meter for more than 2 weeks,
remove the batteries.
If the switch is in the “ 0 ” position, the batteries are disconnected. After installing
batteries be sure to move the switch to the “ | ” position.
CAUTION DO NOT use the hardware power switch to turn the 831C OFF. Permanent
damage and data loss may occur. Press the Power button once, then select
Off.
2.2 Powering the 831C SLM
In this section:
•2.2.1 Using Battery Power
•2.2.2 Using External Power
•2.2.3 Understanding 831C Power Events and Indications
2.2.1 Using Battery Power
Current Battery Voltage is displayed on the Power Control page. To access the Power
Control page, press the Power button 0.
In the Status Bar section of the meter display, the battery icon indicates the state of the
battery charge by the color and fill.
CAUTION Do not mix different types of batteries. Only charge NiMH batteries.
CAUTION Do not mix batteries from different manufacturers, replace all 4 batteries at
the same time.
CAUTION When changing batteries, select the correct Battery Type in System Prop-
erties. See 9.4.1 Changing Batteries and Editing the Battery Type.
CAUTION Resolve a Session Log entry “Charging Stopped” by checking the batteries,
and ensuring the correct battery type is selected in System Properties.
Additionally, the battery may be too old to charge. Battery may also be read
as an incorrect battery type, which may happen to fully discharged NiMH
batteries. Use an external battery charger to restore charge, then install in
meter. Additionally, the batteries may be too hot or too cold.
Full Charge Low Charge

SoundAdvisor Model 831C Powering the 831C SLM 12
CAUTION The 831C is compatible with Energizer, Duracell, and other commercially-
recognized brands of these battery types:
• AA nickel metal hydride (NiMH)
• AA Alkaline
• AA 1.5 Volt Lithium
CAUTION Optimal battery temperature is 0° C–45° C.
Understanding the Low Battery Indication
As the battery nears the end of expected life, the empty battery symbol begins to flash.
When the battery is no longer functioning, the 831C stops running, saves all data and
instrument status, then turns off. When you power the 831C again with fresh batteries or
an external power supply, the unit returns to the state it was in prior to shutting down.
Installing Batteries
The battery compartment of the 831C is on the back of the instrument. When installing
batteries, always insert 4 fresh AA batteries, and observe polarity markings as shown in
Figure 2-3
FIGURE 2-3

SoundAdvisor Model 831C Powering the 831C SLM 13
Charging Batteries in the 831C
You can charge batteries (NiMH only) in the meter in about 7 hours when the meter is
powered off.
Before you begin:
• Install batteries as shown in "Installing Batteries" on page 12.
Step 1. On the 831C, press Tools 3  System Properties.
Step 2. Select NiMH as the Battery Type.
Step 3. The Charge drop-down menu is automatically set to On. If you do not want
your power source to charge the batteries, select Off.
Step 4. Select Save, then click Yes to confirm your choice.
TAKE NOTE Batteries charge more efficiently when the meter is powered off. For details
about 831C button LED indicators, see “Understanding Charging Status LED
Indications” on page 13.
Step 5. Power the meter off.
Step 6. Connect the meter (with the USB cable) to the included power cable (PSA029),
and plug this in to a wall outlet or other external power source.
TAKE NOTE If you’re using a power cable other than the one supplied with the meter, use
a 28 AWG or larger wire for proper charging.
Understanding Charging Status LED Indications
The charge status indicated by the green LED behind the Power button is as follows:
• Solid green: Charging
• No green light: Not charging
• Green light wink: Maintaining charge
• Green light fast blink (two times per second): Charger fault
• Green light fastest blink (three times per second): Meter is powering onor
shutting down
Resolving a “Charging Stopped” Session Log Entry
To resolve a “Charging Stopped” Session Log entry, check the battery placement, and
make sure the correct Battery Type is selected (Tools  System Properties).
Resolving an “Incorrect Battery Type” Session Log Entry
Infrequently, when the battery becomes too old to charge, the meter may register the
battery as the incorrect battery type. This can also occur when newer NiMH batteries are
fully discharged. In this case, charge the batteries using an external battery charger, then
install them in the meter.

SoundAdvisor Model 831C Powering the 831C SLM 14
You may also see this error when the batteries become too hot or too cold. Optimal battery
temperature is 0° C–45° C.
2.2.2 Using External Power
The following available external power sources augment the 831C’s internal battery:
• USB port from a computer
• USB port from PSA029 power supply
• I/O connector from an external +10.8 to +25 Volt DC mains power source.
Accessing External Power by Using the USB Port
Step 1. Connect the PSA029 power cable to an external power source on one end and to
the included USB Type B power cable (CBL138) on the other end.
Step 2. Then insert the mini-USB (Type B) connector into the mini USB (Type B) port on
the bottom of the meter.
CAUTION If you operate the 831C without batteries and power is interrupted, you may
loose your data.
With the PSA029 power supply connected and operating at rated conditions, the 831C
operates properly with or without batteries installed. Use the included cable (or another
cable with the same gauge wire) to prevent excessive power loss.
2.2.3 Understanding 831C Power Events and Indications
Understanding a Low Voltage Shutdown Event
The 831C preserves the service life of an external battery by preventing it from being
discharged excessively. When the battery voltage drops below the External Shutoff Voltage
(default value +10.8 volts) and remains above +10.2 volts for one minute, the instrument
stops, saves data, and turns off.
Understanding a Power On After Power Loss Event
When the 831C is powered from an external supply and the input voltage falls below the
indicated External Shutoff Voltage threshold, it powers off. When the 831C shuts down due
to a low battery, it automatically attempts to power up after a short reprieve. If there’s
adequate power, it remains on. However, if the battery is still discharged, it powers off. This
attempted “power on” cycle continues until the meter has sufficient power to remain on.
This feature is designed to allow the 831C to automatically restart when power is lost due
to low solar situation or after an extended power outage.
LEARN MORE To learn more about reboot time after a power loss, see “Low Power At
Boot-Up” on page A-7.

SoundAdvisor Model 831C Powering the 831C SLM 15
Understanding a Sudden Loss of External Voltage Event
When the external voltage is suddenly lost—if the external supply is disconnected or the
main power fails and there is no external battery—the 831C continues to run on internal
batteries if they are present and in good condition. If battery power is not present, the
831C immediately switches to an internal recovery battery and powers down safely.
Understanding the External Power Indicator
When connected to an external power source using the included USB cable, the External
Power icon replaces the Battery icon.
If your meter has fully-charged NiMH batteries and is plugged into a power source, this icon
indicates that it’s using power from the external source, and is not charging or using any
power from the batteries.
Understanding a Low Power at Start Up Indicator
At start up, the 831C performs a power check. If the supplied power is too low, the low
power icon displays over top of the first display. For more information see Table A.5, “Low
Power At Boot-Up”.
Understanding Low Input Power Indicator
When “Low Input Power” displays on the Power Control Page (see Figure 2-4 on this page),
the USB cable cannot supply sufficient power to charge the internal batteries. To resolve
this issue, contact Larson Davis (see back cover of this manual) and request the CBL138—
which is a 3-foot, USB 2.0 A Male to Mini-B, 5-pin Male 28/24 AWG Cable with Ferrite Core.
2.2.4 Powering On or Off
Powering On
Press and hold the ON/OFF button 0 on the meter until the screen flashes and the green
LED under the button lights up.
Powering Off
There are 3 ways to power off the 831C:
1. Press the ON/OFF button 0 once to access the Power Control page, then press the
top-left softkey to select Off.
2. From any screen, press and hold the ON/OFF button 0 for 3 seconds to begin the
shut down sequence.
3. Press and hold the ON/OFF button 0 for 10 seconds to force an immediate
shutdown. CAUTION: Using this method may result in lost data.