QSC CM16a User manual

CM16a
Amplifier Network Monitor
HARDWARE MANUAL
TD-000086-00
TD-000086-00
Rev. A

¨ WARNING ¨
While QSC has endeavored to develop and produce the most depend-
ableandrobust‘network’audioproductforyouruse,duetothemyriad
of network situations and equipment that may be encountered in its
implementation,QSCcannotbeheldresponsiblefornetworkconflicts
and associated consequences that may result. For this reason, QSC
strongly recommends that the network used for implementa-
tion of QSControl products be completed separate from all
other networks, data or otherwise. As such, should you elect to
integrate QSControl products with your existing network system, all
risks attendant to such integration of QSControl products with your
existing network or network systems are assumed by you. While QSC
strivestoprovidethehighestqualitytechnicalsolutionsfornetworked
audio products, in no event will QSC or its suppliers be held liable for
any damages, consequential, incidental or otherwise, including any
claims for lost profits and/or savings resulting from any attempted
integration of QSControl products with your networking systems. No
agent,employee orrepresentative ofQSC hasany authorityto alteror
modify in any manner, the disclosures and recommendations set forth
herein.
© Copyright 2000, QSC Audio Products, Inc.
QSC®is a registered trademark of QSC Audio Products, Inc., Costa Mesa, CA
“QSC”and the QSC logo are registered with the U.S. Patent and Trademark Office
“HyperTerminal”is the copyrighted property of Hilgraeve Inc., Monroe, MI
“Phoenix Contact”is the trademark of Phoenix Contact, Inc., Middletown, PA
“Riacon”is the trademark of RIA electronic, Inc., Eatontown, NJ
“On-Shore Technology”is the trademark of On-Shore Technology, Inc., Tempe, AZ
All other trandemarks are the property of their respective owners
2

TABLE OF CONTENTS: CM16a Amplifier Network Monitor
Section 1: INTRODUCTION Overview...................................................................................................5
Physical Characteristics & Layout........................................................6
List of Functions & Features...................................................................8
Block Diagram.........................................................................................9
Detailed Description of Functions.......................................................11
Network Description.............................................................................14
Network Examples................................................................................15
Section 2: INSTALLATION Basics: Unpacking............................................................17
What is Included.................................................17
Location Considerations....................................17
Mounting the CM16a..........................................17
Connecting: AC Power..............................................................18
Audio Inputs.........................................................19
Page Input............................................................20
RLY/TRG Input......................................................20
RLY Output............................................................20
Monitor Chain In/Out..........................................20
10BASE-T Input/Output........................................21
RS-232 Port...........................................................21
Amplifiers.............................................................21
Rear Panel Detailed Illustration & Hookup Example........................22
Section 3: OPERATION General: Amp Setup, Network Setup...............................24
LED Behavior........................................................25
BYPASS Switch Usage......................................25
Serial Port Interface...........................................27
Telnet Access......................................................30
Fuse Replacement...............................................31
Section 4: SPECIFICATIONS.......................................................................................................................................32
Section 5: ARCHITECT’S & ENGINEER’S SPECIFICATION..................................................................................36
Section 6: APPENDIX Ethernet Cable & RS-232 Pinouts ........................................................37
DataPort Pinout and “Phoenix”-type Connector Part Numbers......38
Section 7: QSC INFORMATION How to Contact QSC Audio Products..................................................39
3

EXPLANATION OF GRAPHICAL
SYMBOLS
The lightning flash with arrowhead sym-
bol, within an equilateral triangle, is in-
tended to alert the user to the presence of
uninsulated “dangerous voltage” within
the product’s enclosure that may be of
sufficient magnitude to constitute a risk of
electric shock to humans.
The exclamation point within an equi-
lateral triangle is intended to alert the
users to the presence of important op-
erating and maintenance (servicing) in-
structions in the literature accompany-
ing the product.
CAUTION: To reduce the risk of electric shock, do not
remove the cover. No user-serviceable parts inside.
Refer servicing to qualified service personnel.
WARNING: To prevent fire or electric shock, do not
expose this equipment to rain or moisture.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
ATTENTION: Pour eviter les risques de choc électrique,
ne pas enlever le courvercle. Aucun entretien de pièces
intérieures par l’usager. Confier l’entretien au personnel
qualifié.
AVIS:Poureviterlesrisquesd’incendieoud’électrocution,
n’exposez pas cet article à la pluie ou a l’humidité.
AVIS
RISQUE DE CHOC
ÉLECTRIQUE
NE PAS OUVRIR
VORSICHT: Um das Risiko eines elektrischen Schlages
zuvermindern,Abdeckungnichtentfernen!KeineBenutzer
Wartungsteile im Innern. Wartung nur durch qualifiertes
Wartungspersonal.
WARNUNG: Zur vermeidung von Feuer oder elektrischen
Schlägen, das Gerät nicht mit Regen oder Feuchtigkeit in
Berührung bringen!
VORSICHT
GEFAHR EINES
ELEKTRISCHEN SCHLAGES.
NICHT ÖFFNEN!
SAFEGUARDS
Electrical energy can perform many useful functions.
This unit has been engineered and manufactured to
assure your personal safety. Improper use can result
in potential electrical shock or fire hazards. In order
not to defeat the safeguards, observe the following
instructions for its installation, use and servicing.
PRECAUTIONS
L’énergie électrique peut remplir de nombreuses
fonctions utiles. Cet appariel a été conçu et réalisé
pour assurer une sécurité personnelle entiére. Une
utilisation impropre peut entraîner des risques
d’électrocution ou d’incendie. Dans le but de ne pas
rendre inutiles les mesures de sécurité, bien observer
lesinstructionssuivantespourl’installation,l’utilisation
et l’entretien de l’appareil.
EXPLICATION DES SYMBOLES
GRAPHIQUES
Le symbole éclair avec point de flèche à
l’intrérieur d’un triangle équilatéral est
utilisé pour alerter l’utilisateur de la pres-
ence à l’intérieur du coffret de “voltage
dangereux”nonisoléd’ampleursuffisante
pour constituer un risque d’elétrocution.
Le point d’exclamation à l’intérieur d’un
triangle équilatéral est employé pour
alerter les utilisateurs de la présence
d’instructions importantes pour le
fonctionnement et l’entretien (service)
dans le livret d’instruction accompagnant
l’appareil.
ERKLÄRUNG DER GRAPHISCHEN
SYMBOLE
Der Blitz nach unten zeigendem Pfeil in
einem gleichseitigen Dreieck weist den
Benutzer auf das Vorhandensein einer
unisolierten,“gefährlichenSpannung“ im
Gehäuse hin, die stark sein kann, einer
Person einen elektrischen Schlag zu
versetzen.
DasAusrufzeichenineinemgleichseitigen
Dreieck weist den Benutzer auf wichtige
Betriebs- und Wartungs- vorschriften in
den beiliegenden Unterlagen des Gerätes
hin.
Federal
Communications
Commission (FCC)
Information
NOTE: This equipment has been
tested and found to comply with
the limits for a Class A digital
device, pursuant to Part 15 of the
FCC Rules. These limits are de-
signedto providereasonablepro-
tection against harmful interfer-
enceinacommercialinstallation.
This equipment generates, uses,
and can radiate radio frequency
energy and, if not installed and
used in accordance with the in-
structions, may cause harmful in-
terference to radio communica-
tions.Operationofthisequipment
in a residential area is likely to
cause harmful interference, in
which case the user will be re-
quired to correct the interference
at his or her own expense.
4

Section 1: Introduction- Overview
The QSC CM16a Amplifier Network Monitor provides powerful
amplifiermanagementandzonepaging capabilityin aQSControl
networked audio system using Ethernet networking technology
to communicate with the host computer/system controller.
FromallofusatQSCAudioProducts,thankyouforyourpurchase.
The host computer uses the QSControl application software to
operatethe networkedaudio system,includingthe CM16a’sand
their amplifiers. The software operates on the Microsoft Win-
dows NT® version 4.0 operating system and can be customized
usingMicrosoft®VisualBasicProfessionalEdition. Thenetwork
may theoretically have hundreds of CM16a’s but the real-world
limitation is determined by the network bandwidth, type and
configuration.
This manual is intended to be a reference for installing and
connectingtheCM16aaswellasoutliningthehardwarecapabili-
ties of the CM16a. The actual operation of the CM16a is depen-
dant upon the instructions received from the control software.
Note that not all hardware features may be supported by the
current software revision. Please refer to the software’s docu-
mentation or help file for information regarding software fea-
tures, usage and functions.
The CM16a performs control and monitoring functions for QSC
amplifiers equipped with a DataPort. This could be up to eight 2-
channel or four 4-channel amplifiers (or some combination of
these). The amplifiers that are supported by the CM16a are the
PowerLight,PL2, DCA, andCXseries ofQSCamplifiers thathave
a built-in Data Port. Models that do not have a built-in DataPort
or models that have a DP-1 option (such as the EX and MXa
series) are NOT supported by the CM16a.
TheDataPort connectionsare madewithordinary VGAcomputer
monitor-type cables (HD-15 male-to-male). These cables are
the same type that are used on personal computer systems to
connect the monitor to the computer. This allows you to use
commonly available cabling for interconnecting amplifiers to the
CM16a. Each DataPort connection supports the control and
monitoring functions for two audio channels. When using the
CM16a with amplifiers that have more than two channels (such
as the 4 channel cinema amplifiers) additional DataPort connec-
tions are required.
The CM16a is not a “plug-and-play” replacement for the CM16.
TheCM16ahasamuchimprovedfeature-setandheighthasbeen
reduced from 2RU to 1RU. Additionally, connectors are slightly
differentbetween thetwo. Weight hasbeen reducedfrom 22 to
11 pounds.
A final note; The CM16a is a control and monitoring device that
relies on software to do its job. The functions and capabilities
provided in the design of the CM16a can only be realized with
propersoftwareimplementation.Keepinmindthatthismanual’s
intent is to outline these capabilities and provide a reference for
properly installing and interconnecting the CM16a to the net-
worked system’s host computer, the audio inputs and the ampli-
fierstobecontrolledandmonitored.Athoroughknowledgeofthe
control software’s features and operation will provide the best
possible results for the end user.
Note: In this manual, bold type (e.g. PORT A) within the para-
graph text indicates a control or connection that is labeled
similarly on the CM16a.
5

Section 1: Introduction- Physical Characteristics & Layout
PHYSICAL CHARACTERISTICS
Each CM16a is one rack space in height (1RU) and has an internal AC power supply. Its chassis depth is 37.7 cm (14.84 in.). The width of
the chassis is 44.0 cm (17.32 in.). For the detailed mounting dimensions, please see specification section. The weight of the CM16a is
approximately 5 kilograms (11 pounds).
FRONT PANEL (numbers correspond to reference locations shown in illustration to right)
The front panel of the CM16a includes:
1- AC OFF / POWER switch
2- Cooling air exhaust vents (intake vents on left side of chassis as viewed from the front)
3- AC POWER indicator LED
4- DIAGNOSTIC indicator LED
5- Network status indicator LED’s ( RCV, XMT and LINK STATUS), duplicated on rear panel for convenience
6- PORT A through PORT H connection indicator LED’s
7- Access hole for the BYPASS switch ( this is not labeled on the panel )
REAR PANEL (numbers correspond to reference locations shown in illustration to right)
The rear panel of the CM16a has duplicates of the RCV, XMT and LINK STATUS indicator LED’s so that network status can be detected
from the rear of the unit when installed in the equipment rack. The rear panel provides the following connections:
8- Eight HD-15 receptacles (PORT A through PORT H) for connection to amplifiers with VGA-type cables
9- Sixteen “Phoenix”-type (Euro-style) 3-pin receptacles for audio inputs (PORT A CH 1 through PORT H CH 16)
10- One “Phoenix”-type 5-pin receptacle for audio monitoring functions (MONITOR CHAIN,IN and OUT)
11- One “Phoenix”-type 3-pin receptacle for paging audio signal input (PAGE)
12- One “Phoenix”-type 2-pin receptacle for remote sensing (example: detecting a switch closure or logic event; RLY / TRG IN)
13- One “Phoenix”-type 3-pin receptacle for access to SPDT relay contacts (used for remote switching of external devices; RLY OUT)
14- One RJ-45 type receptacle (10BASE-T Ethernet computer network connection)
15- One DB-9 type receptacle (RS-232 Port for network and firmware utilities)
16- IEC-type detachable AC power cord receptacle (for connection to AC power line) with integral fuse holder
6

Section 1: Introduction- Physical Layout Diagram
7

Section 1: Introduction- List of Functions & Features
FUNCTIONAL LISTING, BLOCK DIAGRAM & DETAILED DESCRIPTIONS
The CM16a performs control and monitoring of amplifiers remotely. Below is a listing of the functions that are available for the supported
QSC amplifiers. The following two pages (Block Diagram part 1 & 2) graphically illustrate the main functions of the CM16a. Following the
diagram is a section giving detailed explanations on each functional block that will aid in the use of the CM16a. Note that not all features
may be supported by the current revision level of software (consult software documentation for supported feature set). Where applicable,
functions are available on each individual channel.
CONTROL FUNCTIONS
Amplifier: Power (Standby/Operate Control)
CM16a: Input Sensitivity Select Input Source Select (Normal/Page)
Signal Level Control Signal Mute
Signal Polarity Select Paging Control (with customizable routing)
Contact Closure Output (switching of internal relay for control of external device)
Paralleling within DataPort Pair
MONITOR FUNCTIONS
Amplifier: Power Status Amplifier Gain
Amplifier Model Bridge Mode
Load Monitor (impedance) Protection Status
Output Voltage Output Current
Output Power (real) Heat Sink Temperature (with Over-Temp.)
Headroom Clipping Detect
Output Short Output Open
Output Level Meter
CM16a Input Level Meter Output Level Meter
Audio Monitor Module (4 channel mono. mixer)
External Event Sensing (a logic-level or switch input)
SPECIAL FEATURES
DAC (digital-to-analog converter) that can be used for generating test signals & the playback of paging messages
RS-232 Port for setting of network address information
TFTP upgradeable firmware
8

Section 1: Introduction- Block Diagram (part 1)
The following diagrams illustrate the basic functional blocks of the CM16a. Keep in mind that the first diagram is “duplicated” for each of the eight ports.
9

Section 1: Introduction- Block Diagram (part 2)
10

Section 1: Introduction- Detailed Description of Functions
AUDIO FUNCTIONS
Audio Inputs- These are the “Phoenix”-type 3 pin connec-
tors used for balanced line level audio-signal input.
InputSensitivity- Sets the sensitivityofthe Audio Inputsto
either 1 Volt or 3 Volts (r.m.s.). This selection should coincide
with the level of the audio signal provided for each channel.
Input Source: Normal/Page- Selects the input source for
each channel. Normal input is the audio connected at the
AudioInput terminals.Pageinputistheaudioprovidedbythe
Paging Input Module.
Level Control- Provides adjustment of the signal level
deliveredtotheamplifierforeachchannel.Adjustmentisfrom
-95.5dB to 0dB in 1/2dB steps.
Meter-Thesepoints areindicators ofwherein theaudio path
the software can “meter” the audio.
Mute- Actively mutes the audio signal being passed by a
channel.Nosignalisdeliveredtotheamplifierwhenachannel
is muted.
ParallelMode- Whenparallelmodeis selected,theinput to
the first channel is also applied to the second channel. When
in parallel mode, the input is ALWAYS from the first (or odd
numbered) input. The second (or even numbered) input is
ignored; this includes the PAGE signal. This feature is useful
forsendingoneinputsignaltobothamplifierchannelswithout
having to wire jumpers between the two input connectors.
Polarity- Determines the polarity of the signal delivered to
the amplifier for each channel.
AUDIO MONITOR CHAIN FUNCTIONS
Pre-Fader Monitor- Monitors the audio path at the point
before the Level Control block (i.e. the input to the CM16a).
Post-Fader Monitor- Monitors the audio path at the point
after the Level Control, Mute , and Polarity blocks (i.e. the
output from the CM16a).
Amplifier Monitor- Monitors the audio at the output of the
amplifier (i.e. the speaker terminals of the amplifier).
Off- This selection disconnects the monitor for the channel.
Level Adjust- Provides adjustment of the signal level deliv-
eredto the MonitorModule from eachof theselectable “tap”
points of a channel’s audio path. Adjustment is from -95.5dB
to 0dB in 1/2dB steps.
Monitor Module- This module functions as a four-input
mixer with software selection of the input channels. The four
selectedchannelsaresummedwiththe externalinput Moni-
tor Chain In . For each of the inputs, the “tap” point is
selectable from the pre-, post-, amplifier and off positions.
AMPLIFIER CONTROL FUNCTIONS
Standby/ Operate- Controls the amplifier’s power status-
ON - amplifier operational
STANDBY - amplifier in standby mode
NOTE! The amplifier must be powered in order to respond to
any commands issued by the CM16a
11

Section 1: Introduction- Detailed Description of Functions
AMPLIFIER MONITORING FUNCTIONS
Amplifier Model Detect- Identifies what model of
QSC amplifier is connected to the CM16a’s DataPort.
Amplifier Gain Detect- Reports the setting of the
amplifier’s gain setting (in dB) for each channel.
Bridge Mode Detect- Detects the position of the
bridge mode switch on each amplifier.
Clip Detect- Detects amplifier clipping on each chan-
nel.
Headroom Metering- Reports the “available” re-
maining signal level that the input signal can be driven
before clipping will occur.
Heat Sink Temperature Metering- Monitors the
heatsinktemperatureofeachchannelofeachamplifier
connected to the CM16a. If the temperature exceeds a
userspecifiedvalue(insoftware)thentheOver-Temp.
“object” will alert the system operator.
Load Monitor Detect- Monitors the impedance of
the load at the amplifier output for each channel.
Output Current Meter- Provides for metering of the
amplifier’s output current on each channel.
Output Voltage Meter- Provides for metering of the
amplifier’s output voltage on each channel.
Output Open Detect- Detects when the load con-
nected to the amplifier is above a user specified value
in software.
Output Short Detect- Detects when the amplifier
load is below a user specified value in software.
Power Status Detect- Reports AC power status of
the amplifier (ON/standby/ OFF).
Protect Status Detect- Reports if the amplifier has
entered “protect” mode (such as thermal, over-current
or power-up muting protect status).
Real Power Detect- Reports the “real” power the
amplifier is delivering. This “real” power is not the
same as “reactive” power.
ThresholdAdjust- Thisindicates thatthe behavior of
the associated block requires the input of a threshold
valueinsoftwarethatmustbecrossedforthedetection
to occur. This allows the system operator to tailor the
behavior of the system to each application.
PAGING FUNCTIONS
Input Sensitivity- Sets the sensitivity of the Page
Input to either 1 Vrms or 3 Vrms. This selection should
coincide with the level of the audio signal provided for
the Page Input.
DAC- This is a digital-to-analog converter that takes
digital information from the internal microcontroller
and outputs the corresponding analog “equivalent” to
the appropriate channel PAGE insert points . This oc-
cursonly byinstructions issuedby thesystem operator
or a custom control application. It can be used for a
variety of purposes from the playback of “canned”
paging messages to testing of the complete system.
Internally, this function is placed within the PAGING
INPUTMODULEasshownintheblockdiagram.Analog
Page Input is disabled when using the DAC.
PageInput- This is the“Phoenix”-type3 pin connec-
tor used for balanced line level analog page audio-
signal input.
12

Section 1: Introduction- Detailed Description of Functions
RS-232 PORT FUNCTIONS
RS-232 Port- The RS-232 (serial) port is used to
communicate with the CM16a for Ethernet address
setup purposes and other diagnostic purposes. Most
userswill never have a need to accessthe RS232 port,
but for customized networks and for troubleshooting
system problems, it may be necessary.
For the RS-232 port utilities, see the Operation
section, “Serial Port I/O Interface”. This section
outlines the proper connection and communica-
tion settings required to communicate with the
CM16a via the serial (RS232) port.
If the CM16a is connected to an Ethernet network
where the factory-provided Ethernet address informa-
tion is not acceptable, a configuration utility must be
run. This involves connecting a computer with a prop-
erly configured serial port to the CM16a using a null-
modem type cable (such as a “Laplink” cable) and
running a dumb-terminal program (HyperTerminal is
theMicrosoft®Windows-suppliedprogram).DONOT
CHANGE THE FACTORY SETTINGS UNLESS YOU ARE
CERTAIN OF WHAT YOU ARE DOING! If addressing is
configured incorrectly, the CM16a may not respond to
network control.
CONTACT CLOSURE I/O FUNCTIONS
RLY OUT- This is used for remotely controlling an
electricaldevice in anon/offmanner (suchasa cooling
fan, an audible alarm, a light, etc.). An internal SPDT
(single-pole, double throw) relay is controlled by soft-
ware command. Its contacts are accessible at the rear
panel RLY OUT connector and are labeled:
NC (normally closed)
NO (normally open)
C(common)
RLY/TRG IN- Detects the closure (or opening) of a
switchconnectedtotheRLY/TRIGINterminalson the
rear panel. Also accepts CMOS and TTL logic-level
inputs. An example is the detection of a limit-switch
that indicates an open door on an equipment cabinet.
13

Section 1: Introduction- Network Description
14
QSC CM16a Amplifier Network Monitors are designed to operate on standard 10BASE-T Ethernet. Each CM16a operates as a
respective node on its network; each unit contains a programmable IP address in nonvolatile memory and will therefore present no
conflictwithanyothernodeonthesamenetwork. Ethernetdevicessuchashubs,repeaters,switches androuterswillusuallyafford
the flexibility to configure the network as needed.
The system controller computer on the network must have an Ethernet-compatible network interface card (NIC) installed.
Additionally,if operationduring poweroutage orinterruption isrequired, anuninterruptable power supply(UPS) willbe requiredfor
the host computer , CM16a, and any hubs, switches or repeaters. If the CM16a is disconnected from the network for any reason, it
will continue to process audio using the last settings.
TheCM16aconnects tothenetworkvia its RJ-45connectoronthe rearpanel.This allowsdirect connection toa10BASE-Tnetwork.
UseCategory 3 (orbetter)unshielded twistedpair(UTP) Ethernet Cable.Mostready-made Ethernetpatchcables available todayare
rated at least Category 5 making them suitable for this application.
OnesidenoteregardingEthernetcabling:AlthoughCategory3datacableiscalledoutastheminimumrequirement,itisincreasingly
difficult to find. Higher grades of cable are becoming the “normal stock” with the proliferation of 100BASE-T Ethernet. Category 5
Ethernet cable is the most widely available type of data cabling as of this writing. So what does this mean? Use Category 3 if it is
availableandcosteffective.IfthecostofCategory5cableisnotprohibitive,itmaybedesirabletodoyourcablingruns withCategory
5 due to its increased data rate capabilities. The extra capability may be needed for future system expansion where 100 BASE-T
devices are used. 10BASE-T capability is all that is required for the CM16a and thus the call out for Category 3 as the minimum.
There are three LED indicators on the CM16a that relate to network operation. They are described
Section 3: Operation .

Section 1: Introduction- Sample Network Topologies
Thesimplestnetworkconfiguration is asingle
system controller computer and a CM16a con-
nected by a single Ethernet
crossover cable. A
standard Ethernet cable would NOT work. The
crossover-type cable must be used when con-
necting the CM16a directly to the system con-
troller computer. This type of cable switches
(or crosses over) the transmit and receive sig-
nals from one end to the other enabling con-
nection without a hub or repeater.
For distances longer than 100 meters (~300
feet) a repeater must be used. An active hub
may be used as well. Active hubs “clean up”
and retransmit the network traffic, much as a
repeater does, only with multiple ports. The
active hub would allow for future expansion.
Ifthereare two ormoreCM16a’sin
the network (or other network de-
vices present) use a hub to create a
star topology.
15

Section 1: Introduction- Sample Network Topologies
Some networks have multiple system con-
troller computers. This configuration is es-
sentially the same as the second example
with the addition of the second computer
attached to the hub.
To create the more complex distributed star
topologies needed for larger systems, use
additional hubs. Some hubs have special
uplink ports for connecting to other hubs via
astandard Ethernet cable. If thehubs donot
have uplink ports, then the hub-to-hub con-
nectionshoulduseacrossover-typeEthernet
cable.
16

Section 2: Installation- Basics and Mounting
UNPACKING
TherearenospecialunpackingprecautionsfortheCM16a.However,itisrecommendedthatyoukeeptheoriginalpackingmaterialforreuse
in the rare event that service be required on the CM16a. If service is required and the original packing material is not available, ensure that
the unit is adequately protected for shipment (strong box of appropriate size, sufficient packing material to prevent impact damage or load
shifting).
WHAT IS INCLUDED IN THE CARTON
1- CM16a Amplifier Network Monitor
2- AC Power Cord
3- One complete set of the “Phoenix”-type connectors (18 pcs. of 3-pin style, 1 pc. of 5-pin style & 1 pc. of 2-pin style)
4- Hardware manual (this document)
LOCATION CONSIDERATIONS
Wherethe CM16a isinstalledis dependentuponthelocation ofaudioinput sources, amplifiers andnetworkaccess. Thesystemcontroller
computer should be located someplace convenient for the system operator. In most instances, the system controller computer is remote
from the CM16a and the amplifiers . It is preferable to install the CM16a and the amplifiers in the same or adjacent equipment racks; this
allows thecablingbetweenthemtobestandardVGAmonitorcables.Thesecablesaregenerally2 meterslong(6.5feet).Forlongercabling
runs, contact QSC’s Technical Services Department at [phone] (toll free U.S.A. only) or [phone]. QSC offers a special cable
with individually-shielded twisted-pairs for each audio path; this cable can be used over distances as long as 100 meters (328 feet).
The maximum length of any 10BASE-T Ethernet network segment (cabling between any node and the next node, hub or repeater) is 100
meters(328feet).Thelocationofhubsandrepeatersmustbesuchthatthisdistancelimitisnotexceeded.Ifthisisimpracticalorimpossible,
then use appropriate network transceivers and fiber optic cabling. For larger Ethernet networks, the use of Ethernet routers may be
necessary.
MOUNTING THE CM16a
The CM16a is secured to the equipment rack with four screws and washers. Be sure to support the weight of the CM16a when securing
to avoid distorting or bending the front panel mounting ears. For mobile, touring or portable applications, support the rear of the CM16a
using the rear mounting tabs provided or contact QSC’s Technical Services Department to order rear rack ear extensions. The rear rack ear
extension kits add flexibility to you installation options as well as a support-pin option that requires one-time hardware installation at the
rear of the rack. For the locating dimensions of the rear support mounting tabs, see the dimensional diagram in the specification section.
17

Section 2: Installation- Mounting and AC Power
MOUNTING THE CM16a (continued): The illustration below shows the basic mounting technique.
The CM16a uses fan-drawn air for cooling. The air intake is on the left side of the chassis and the exhaust vents are on the front panel. Be
certain not to obstruct these openings! Allow ample “open space” around them in order to maintain unobstructed air flow.
NotethattheCM16a’srecommendedambientoperatingtemperatureis0°C.to50°C.(32°F.to122°F.).Donotinstall
the CM16a in environments that expose it to temperatures outside this range. Keep in mind that some
equipment rack installation environments can get quite hot. If there is any question, measure the air temperature
inside the equipment rack and supply additional cooling (air flow) to keep the ambient temperature within the
specified limits. QSC amplifiers use back-to-front air flow and therefore do not exhaust hot air into the rack.
CONNECTING AC POWER
The CM16a uses a detachable IEC standard power cord for connecting to a grounded AC
source. To connect power to the CM16a: identify the proper end of the cord, match the
orientation of the receptacle on the rear panel and insert firmly into the receptacle. The
powersupplywillacceptfrom85to264VoltsAC,47to440Hertz,withoutanychanges.Make
sure that the power cord used is suitable for the line voltage that the CM16a is connected
to. If a different type of IEC power cord is required (different style of plug on the outlet end)
contact QSC’s Technical Services Department to obtain the correct cord assembly.
DONOT CONNECTTHECM16aTO POWERSOURCESOUTSIDE THESPECIFIEDRANGES OFVOLTAGEOR
FREQUENCY! DAMAGE TO THE UNIT COULD RESULT OR THE USER COULD BE EXPOSED TO UNSAFE
OPERATING CONDITIONS.
REAR PANEL- POWER CORD RECEPTACLE
18

Section 2: Installation- Connections
CONNECTING AUDIO INPUTS
The audio inputs are located on the rear
panel. The CM16a uses “Phoenix”-type
(Euro-style) terminal block connectors for
the audio inputs. These connectors allow
theinstaller topre-wire theinput termina-
tions before the CM16a is installed in the
rack. It also allows for re-routing of audio
inputs by simply interchanging connector
locations without the need for any tools. See Appendix for connector manufacturer’s
part number reference.
Balancedconnectionis recommendedforallinputs. Ifunbalancedaudiosources are
used, it is preferable to use an appropriate audio transformer (or other unbalanced-
to-balanced “converter”) to provide a balanced input to the CM16a. If this is not
possible, then it is recommended that the negative terminal and shield terminal be
connected to one another with a jumper wire. The illustrations to the right show the
properconnectionofaudioprograminputsources forbothbalancedandunbalanced
inputs.
The recommended stripping length for the wires is approximately 6 to 8 mm ( 1/4 to
5/16inch).Whenstrippingtheaudiocable,becarefulnottonickorcuttheconductor
strands. After each conductor has been stripped and dressed, insert it fully into the
connector and tighten the retaining screw. When stranded wire is used, carefully
twist the conductor strands together so that when they are inserted into the
connector assembly, no loose strands short adjacent terminals.
Forheavy-dutyinputcables,theuseofconnectorswithintegralstrainrelief
isrecommended.These connectorshave alargeplastictab molded aspart
ofthe assemblywhich providesan areato tapeor tie-wrap thecable to.At
the time of this writing, only the 3-terminal with the strain relief was
available through QSC . See Section 6 (Appendix) for connector part
numbers.
BALANCED INPUT CONNECTION
UNBALANCED INPUT CONNECTION
STRAIN RELIEF
REAR PANEL- AUDIO INPUTS
19

Section 2: Installation- Connections
REAR PANEL- PAGE, RELAY & MONITOR CONNECTIONS
CONNECTING THE MONITOR CHAIN IN/
OUT
The MONITOR CHAIN connector is a five pin version
of the “Phoenix”-type connector. The center pin is the
shield connection for both the input and output of the
monitor chain. Note also that the positive terminal of
the input and output connections are on the outer pins
of this connector.
CONNECTING PAGE INPUT
ThePAGEinputisidenticaltotheAUDIOINPUTconnections.
Please refer to the previous page for connection guidelines.
CONNECTING THE RLY/TRG IN
The RLY/TRG IN connector is a two-pin version of the
“Phoenix”-typeconnector.Whenusingthisinputforaswitch-
closure (or opening) event, the two terminals should be
connectedto theswitch contactsdirectly. Thistype ofevent
detection can be used with relay contacts as well. If used
withalogic-type device,thelow-endof thelogicconnection
shouldbeconnectedtotheminus(–)terminalandtheactive-
end should be connected to the plus (+) terminal. This input
iscompatible withTTL &CMOS logicfamily devices.For the
defined limits of input to this connector , please refer to the
specification section.
CONNECTING THE RLY OUT
The RLY OUT connector provides access to the internal relay’s
contacts for remotely controlling an external low voltage device or
circuit. This internal relay is rated for 70V (DC or ACrms), 250 mA
(switched) and is isolated from ground. There is one common
terminal, one normally-closed contact terminal and one normally-
opencontactterminal.ThesearelabeledasC,NCandNOontherear
panel.Whentherelayisnotenergized,theC terminalisconnectedto
theNCterminalandtheNOterminalisnotconnected;whentherelay
is energized the Cto NC connection is opened and the Cto NO
connection is closed.
.
DONOTCONNECTVOLTAGESEXCEEDING70VOLTS(DCorACrms)TOTHERLYOUTCONNECTOR!DAMAGETOTHECM16aCOULD
RESULT OR CREATE HAZARDOUS OPERATING CONDITIONS!
20