Inter-Tel Imx/Gmx 256 Installation And Field Maintenance Manual

							INTER-TELPRACTICESIMX/GMX 256 INS~TION & MAlNTENANCESPECIFICATIONSIssue 1, November 1994
Inward Dialing Cards 
(IDCs)353
IDCs are used for connecting direct inward dial-
ing (DID) trunks and off-premises single-line stations.
Like 
SLCs (described on page 2-12), IDCs may also beused for connecting on-premises single-line sets and
playback devices. In fact, for optimal performance, it is
recommended that voice mail units and automated at-tendant playback devices be installed on IDC circuits
rather than SLC circuits. Doing this mutes any DTMFdigits automatically dialed by the system (e.g., those
generated when transferring or forwarding an outside
caller to voice mail).
NOTE: 
IDCs do not support message waiting applica-
tions. If single-line sets with message waiting lamps are
installed on 
IDCs, the lamps will not function.
3.54On older-version 
IDCs, each IDC circuit has a
2-pin AC ENABLE jumper strap that must be removedwhen installing a DID trunk or a DC-ringing station.
AC-ringing off-premises stations can be connected di-
rectly to IDC circuits provided that both the optional
-48V Module and the optional Ring Generator Moduleare installed in the power supply chassis 
(external
HVRA Units, power supplies, and ring generators are
not needed).
3.55On newer-version 
IDCs, each IDC circuit has a
3-pin RING SELECT jumper strap that must be set ineither the 
AC/OPX position (over the bottom two pins)
or the DC/DID position (over the top two pins).I
NOTE: When setting the jumper straps on either ver-
sion card, note the unique ordering of the 
IDC circuits as
shown in Figure 3-33 on page 3-53.
3.56Each IDC can have up to eight DID trunks or up
to eight single-line sets, or any combination of the two.357
DID trunks may be programmed to ring in to in-
dividual stations, multiple stations, or hunt groups. Or,
they may be programmed 
to ring in as DISAcalls. Ifpro-
grammed to ring in at a single station, the DID call will
follow any programmed forward.
3.58DID trunk groups may be assigned on a 
tenant-
by-tenant basis. Up to 11 DID trunk groups can be dis-
tributed among the tenant groups. Refer to 
FEAWREB,page 4-15, for more information. Also, DID trunk
groups maybe designated as immediate start, wink start,
or delay start in database programming.
3.59Each IDC has 16 specially-designed fuses sol-
dered to the card to protect it 
from large voltage surges
due to lightning. If a fuse is open (blown), it may mean
that other parts of the card have also been damaged. For
this reason, open fuses must not be replaced in the field.
Instead, the entire card 
must be returned for testing and
possible repair. Failure to follow this policy will void the
warranty on the card.
Page 2-15 
						

							SPECIFICA~ONSIssue 1, November 1994INTER-TEL+PRAcTKEsIMXfGMX 256 INSTAT.,LATION & MAINTENANCE
E&M Cards 
(EMCs)
3.60
E&M trunks, also called “tie” lines, are specialtrunks that tie individual telephone systems together.
They allow the users of either telephone system trans-
parent access to the users and resources of the other tele-
phone system, often for less than what it would cost to
use normal long distance service.
3.61E&M (literally “ear” and “mouth”) refers to the
pair of wires that carry the signals between the trunkequipment and a separate signaling unit. The M lead
transmits a ground or battery condition to the signaling
equipment, while the E lead 
receives open or ground sig-
nals from the signaling equipment.
3.62If designated for “auto ring-in,” E&M trunks
may 
be programmed to ring in to individual stations,
multiple stations, or hunt groups on the other telephone
system. (If programmed to ring in at a single station, the
E&M call will follow any programmed forward.)
3.63If designated for “dial repeating,” E&M trunks
may be programmed to ring in as DISA calls.3.64 Additionally, LCR may be used to turn what
would normally be a long distance call into a local call.
For example, when a call is made 
from one telephone
system to a long distance number that is local to the oth-er telephone system, LCR could be programmed to
route the call through the E&M network to make a local
call from the other telephone system.
3.65Each EMC has circuitry for up to four E&M
trunks. Each individual circuit on the EMC has two
jumper straps, one for selecting the signaling type (1,2
4, or 5) and one for selecting the audio type (2-wire or
4-wire). The signaling and audio type for each circuit
must also be programmed in the database.
3.66Although not currently operational, the EMC is
equipped with a “make-busy” switch for removing all
circuits on the card from service and placing them back
in again, The switch is reserved for possible future use.
3.67For optimal E&M trunk transmission perform-
ance, each 
2-wire EMC circuit should be “hybrid bal-anced” in database programming 
(4-wire circuits
cannot be hybrid balanced). Hybrid balancing refers to
selecting the balance network 
- ideal, loaded, or un-
loaded -that best matches the trunk’s impedance. Re-
fer to
PRGGRAh4MlNG, page 5-147, for details.
3.68Should voice transmit or voice receive volumeproblems occur, the receive gain and/or the transmit
gain for individual E&M trunks can be adjusted in data-
base programming. Refer to PROGRAMMING, page
S-103, for additional information.
3.69Each EMC has 24 speciallydesigned fuses sol-
dered to the card to protect it 
from large voltage surges
due to lightning. If a fuse is open (blown), it may mean
that other parts of the card have also been damaged. For
this reason, open fuses must not be replaced in the field.
Instead, the entire card 
must be returned for testing and
possible repair. Failure to follow this policy will void the
warranty on the card.
3.70When the system is in the default configuration,
all E&M trunks are configured for 
IYI’MF signaling and
dial repeating. If necessary, some or all of the trunks can
be reprogrammed for dial-pulse signaling and/or auto
ring-in through database programming.
3.71The E&M circuits are assigned hardware address
numbers according to the card’s slot in the equipment
cabinet and the location of the circuit on the card. For
example, 
E&M circuit 13.4 refers to the fourth circuit on
the 13th card (an EMC) installed in the equipment cabi-
net.
3.72When the system is in the default 
con.&uration,
the 
lirst four trunk keys on each keyset are assigned as
call keys for incoming call indication/access. (The AN-
SWER key may also be used to access incoming calls.)
No individual E&M trunk keys or trunk group keys are
assigned. Key assignments can be designated in data-
base programming. Refer to PROGRAMMING, page
5-44, for more information.
3.73
E&M trunk groups may be assigned on a tenant-
by-tenant basis. Up to 47 E&M trunk groups can be dis-
tributed among the tenant groups. Refer to 
FEAWRES,page 4-15, for more information. Also, E&M trunk
groups may be designated as immediate start, wink start,
or delay start in database programming.
,’i
Page 2-16 
						

							I
SPECIFICATIONSIssue 1. November 1994
NOTE: The acronym for the 
Tl Card -TlC -should
not be confused with the special 
TIC digital carrier sys-
tem (which operates at twice the data rate of the standard
Tl carrier system). The 256 Tl Card does not support
TlC.
3.74The term “Tl” refers to a specific digital method
of transmitting voice and data; it is the basic 
24-chamtel
time-division multiplex 
(TDM), 1.544 Mb/s pulse code
modulation 
(PCM) system as used in the United States.3.75 The 
Ti standard, which was developed as a
method of reducing cabling and increasing transmission
quality between distant central offices, is actually a sub-
set of a multi-level Digital Signal 
(DS) scheme. Inpopu-
lar usage, 
Tl refers to the DSl rate as transmitted via any
type of media (e.g., 
copper wire, fiber optics, or micro-
wave).
3.76Since each 
Tl span actually consists of 24 indi-
vidual circuits (or channels) multiplexed together, it is
often less expensive to purchase a single 
Tl span than it
is to purchase multiple individual trunks. Each of the 24
Tl circuits can be programmed as a loop start, ground
start, DID, E&M, or 
OPXtrunk (or as unequipped). Any
combination is possible.
3.77“Fractional” 
Tl, often called Ffl, is a special Tl
service where only a portion of the 24 channels are used
and paid for. To implement fractional 
Tl (if available),
equip only those circuits that are provided.
NOTE: Currently, the 
Tl Card is used to transmit voice
signals only, not data. In the future, data transmissions
over 
Tl circuits may also be supported.
3.78To interface with the public network, each 
Tl
Card must be equipped with a customer-provided, on-
board Channel Service Unit 
(CSU) or a customer-pro-vided, external CSU. If the optional on-board CSU is
installed, the programmer must select the line build-out
(LBO) attenuation, which is determined by the distance
to the nearest public network 
Tl repeater. (This infor-
mation is available from the 
Tl provider.) If an externalCSU is installed instead, the programmer must select
the DSX-1 line length, which is determined by the dis-
tance from the 
Tl Card to the external CSU. (The card
and the external CSU must be located in the same build-
ing, and the cabling between them must be less than 655
feet.)
NOTIG The on-board CSU can now be purchased
directly from Inter-Tel using part number 440.3004.
3.79Although most 
Tl interfaces will be with the
public network, it is possible to use Tl Cards to connect
two telephone systems together (e.g., two 256 Systems).To do this without 
CSUs, the two systems must be lo-
cated in the same building and the cabling between them
must 
be less than 655 feet. If each system is equipped
with a CSU, they may be 
located in separate buildings
and the cabling between them may be as long as 6000
feet. (See page 3-34 for more information on connect-
ing two 256 
Tl Cards together.)
NOTE: For information on programming various types
of 
Tl installations, refer to pages 5-122 to 5-129.
3.gOIn the future, a Tl span could possibly be used to
connect the 256 System to a host computer via a digitalmultiplexed interface 
@MI). Also, the Tl Card has
been designed to interface with the coming Integrated
Services Digital Network 
(ISDN) features, when avail-
able.
3.81When a 
Tl span is used to connect a 256 System
to the public network or to another telephone system, it
is important that the two endpoints communicate at the
same frequency. Since it is practically impossible for
both endpoints to have clocks running at identical 
fie-
quencies, one endpoint is given “master” clock status
and the other endpoint is given “slave” clock status. The
slave clock can then extract and lock onto the masterclock frequency from the incoming 
Tl information.
This master/slave synchronixation is programmed in the
.database. When connected to the public network, the256 System is automatically designated as the slave
clock.3.82 When information (currently, voice only) is
transmitted over a Tl span, a “framing” bit is added so
that the receiving end can recognize where the informa-
tion begins and ends (as long as the clock circuitry of the
two endpoints is synchronized). Currently, the 256 Sys-
tem supports the two major types of framing schemes in
use today: D4 Super&me, which is the most common,
and Extended 
Superframe @SF), which is required to
support future ISDN and DMI features. For 
voice trans-
missions, D4 
Superframe is quite adequate. However,
for data transmissions (not currently supported), ESF is
much more reliable and efficient.383Digital information is transmitted over the 
Tlspan as a series of 
1s and 0s (e.g., . ..lOOO 000 0000
OOOL..). If there are too many consecutive zeroes, the
Tl clock extraction circuitry will not operate correctly.
To prevent this, 
Tl carrier equipment limits the number
of consecutive zeroes. The 256 System supports the two
major types of 
xero code suppression schemes in usetoday: Alternate Mark Inversion 
(AMI), also called
bit-7 stuffing, and Bipolar Eight Zero Substitution
@QS). Again, for voice transmissions, AMI is quite
adequate. However, for 64 
kb/s clear channel data trans-
missions (not currently supported), 
BSES is required.
Page 2-17 
						

							SPECIFICATIONSIssue 1, November 1994INTER-TELPBACTICESIMX/GMX 256lNSTALLATlON & MAlNTENANCE3.84 Like the 
Tl repeater distance, the framing
scheme type and xero code suppression scheme type are
also available from the 
Tl provider. In fact, when order-
ing a 
Tl span, always request the following information
from the Tl provider:
- Framing scheme: D4 Superframe or ESF
- Zero code suppression scheme: AMI or B8ZS
- If the optional on-board CSU is to be inshlle~ dis-
tance from the MDF to neBrpsf public networkTlrepeater (for determining the line build-out
attenuation): O-1599 feet 
(15dB), 1600-2999 feet
(7.5dB), or 3OO&6000
feet (OdB)
3.85Each TlC has circuitry for up to 24 trunk chan-
nels. The 24 channels (or circuits) can be any 
combina-
tionofloopstarttru&,groundstarttnmks,DIDtrunks,
E&M trunks, or OPX trunks.
3.86The 
Tl Card itself is equipped with the following
resources:l
LED indicators are provided to show the status of
each circuit and to show 
Tl trunk alarms and board-level error occurrences. Refer to the 
TROUBLE!-SHOOTING section of this manual for additional
LED information.
0Audio jack (8-pin, a-conductor modular jack) for
possible future use.NOTE: The audio jack is currently used for engi-
neering diagnostic purposes only.
0 Alarm relay jack @-pin, 8-conductor modular
jack) for connecting optional Tl alarm signaling de-
vices. The 
Tl Card relay contact ratings are:
I= RF’ PY CONTA~ RATINGS
0.6A at 125VAC0.6A at 1lOVDC2.OA at 30VDC
l Serial port jack 
@S-232-C, g-pin, &conductor
modular jack) for possible future use.
NOTE: The serial port jack is currently used for en-
gineering diagnostic purposes only.lTl span jack 
(RJ4SC, g-pin, 8-conductor modular
jack) for connecting a single, 24-channel Tl span to
the 
Tl Card. (If this jack is used, do not use the op-
tional DB15 connector also provided on the card.)
NOTE: All 
Tl spans should be disconnected from
their cards before turning the system power on or off.lDual bantam jack(with transmit and receive audio
ports) for connecting Tl test equipment to the Tl
Card and monitoring the transmit and receive sig-
nals.CAUTION
When a live Tl span is installed on the Tl Card, test
equipment should be used for monitoring purposes
only. Do not attempt to send signals over either the
transmit or receive audio ports on the 
Tl Card if a Tl
span is installed. Also, be sure the test equipment is
set in the “bridge” mode.
0 Optional Tl span DB15 connector (15-pin sub
miniature “D” female connector) for connecting a
single, 
24-channel Tl span to the Tl Card.
NOTE: In certain situations (e.g., when using an ex-ternal CSU equipped with a DB15 connector), it
may be more convenient to use the optional DB15
connector instead of the standard 
RJ48C jack also
provided on the card.
0Make-busy switch with LED for removing all cir-
cuits on the card from service and placing them back
in again. Pressing the switch will light the LED and
begin the process of “busying out” each circuit not in
use. The circuits that are in use are then busied out assoon as the users hang up. When all circuits are
busied out, the make-busy LED and all 24 circuit
LBDs flash slowly, and the card can be removed
from its slot in the cabinet. Ifthe card is not removedwithin a certain amount of time, a programmable
timer expires and the card returns to normal opera-
tion; however, the make-busy LED will then flash
rapidly until the make-busy switch is released.
0Channel Service Unit (CSU) connector for install-
ing the optional on-board CSU Module. If the 
Tl
Card interfaces with the public network, either the
on-board CSU Module or an external CSU must be
connected to the card.
0DSXKSU j&per plug for indicating whether the
on-board CSU is installed. If the on-board CSU is in-
stalled, place the jumper plug in the CSU position. If
there is no on-board CSU, place the jumper plug inthe DSX position. This information must also be
programmed in the database.l
Line build-out jumper plug for selecting the proper
line build-out 
(LBO) attenuation of the Tl span con-
nected to the card. This selection is necessary only ifthe optional on-board CSU is installed. If the dis-
tance between the equipment cabinet and the closet
public network 
Tl repeater is less than 1600 feet,
place the jumper plug in the 15dB position. If the dis-
tance is between 1600 and 2999 feet, place the jump
er plug in the 
7.5dB position. And, if the distance is
Page 2-18 
						

							INTER-TELPRACTIcEsl.MX/GMX 256 INSTALLATION & MAINTENANCESPECIFICATIONSIssue 1, November 1994
between 3ooO and 6000 feet, place the jumper plug
in the 
OdB position. This information, which can beobtained from the 
Tl provider, must also be pro-
grammed in the database.
387Compared to the other trunk cards in the system,
the 
Tl Card is very sophisticated and offers some uniqueprogramming options. The information that is pro-
grammed comnwn to all Tl Cads installed in the sys-
tem includes:
- Dialing feedbackconfiguration: When a number is
dialed over a Tl circuit, the user hears the feedbackfrom the signals (either M’MF or dial-pulse, de-
pending on how the circuit is designated). By adjust-ing the 
M’MF gain control or the dial-pulse gain
control (from -15dB to 15dB), the programmer can
determine how loud the signals appear to the user. If
the circuit is designated for dial-pulse signaling, theprogrammer can also select the type of dial-pulse
tone the user hears (23 different tones are available).
- Error thresholds: The programmer can set muneri-cal thresholds (number per hour and 
number per
day) for certain Tl Card errors. If a threshold is ex-
ceeded, an error is printed on the SMDR report.
- Reference clock back-up priorities: One of the Tl
Cards installed in the system must be programmed
as the system reference clock (see “reference clock
programming” following paragraph 3.88). 
If more
than one 
Tl Card is installed in the system, the pro-
grammer may designate one or more of the cards as a
“backup” to the system reference clock. Then, if the
Tl Card acting as the system reference clock fails or
is taken out of service, the next 
Tl Card on the back-
up priority list takes over.
3.88The information that is programmed specijic to
each 
Tl Cad installed in the system includes:
- Card type: The programmer must select the type of
framing scheme, D4 
Superframe or Extended Super-
frame 
(ESF), used by the Tl span connected to each
card.
- Zero code suppression scheme: The programmer
must select the type zero suppression scheme, AMI(bit-7 
stufling) or Bipolar Eight Zero Substitution
(BSZS), used by the Tl span comected to each card.
-PCM encoding law: In pulse code modulation
(PCM) systems, there are two primary methods ofencoding analog signals (sampled audio wave-
forms) into digital signals. In North America and Ja-
pan, the “mu-law” method is normally used. In otherplaces, like Europe, the “a-law” method is widely
used. The programmer must select both the transmitand receive method of encoding used by the 
Tl
Card. In the UnitedStates, this will almost always be
mu-law to mu-law.
- Relay activation: If desired, the programmer may
enable the two relays, Tl line error and Tl line OK,
on the Tl Card.
- Channel service unit (CSU): The programmer
must designate whether the optional on-board CSU
is installed on the 
Tl Card. (‘The database selection
must match the jumper selection on the card.)
- Line build-out (LBO): If the optional on-board
CSU is installed, the programmer must designate the
LB0 attenuation of the Tl span connected to the
card. This value is determined by the distance to the
nearest public network 
Tl repeater. (The databaseselection must match the jumper selection on the
card.)
- DSX-1 line length: If the optional on-board CSU is
not installed, the programmer must designate the
length of the cabling between the Tl Card and the
external CSU, or between the 
Tl Card and the other
telephone system to which it is connected.
- Reference clock programming: The programmer
must first designate whether the 
Tl Card is con-
nected to the public network. If it is, the card is auto-matically designated as a slave clock (the public
network always acts as the master clock). If the card
is not connected to the public network, but is instead
connected to another 
Tl Card or a card in another
telephone system, the programmer must designate
whether the card is a master clock or a slave clock (in
relation to the card on the other end).
In addition, one of the 
Tl Cards installed in the sys-
tem must be programmed as the system reference
clock. The reference clock then becomes the clock
for all the other cards in the system. If there is no 
Tl
Card acting as the reference clock, the Matrix Card
becomes the system reference clock.
If a 
Tl Card is designated as both a master clock and
the system reference clock, the programmer must
then designate whether the card’s on-board oscilla-
tor is the source of the clock or whether there is an
external clock.NOTE: The external clock option is provided for
possible future use only. For now, always designate
the card’s on-board oscillator as the source of the
clock.
- Test tone: If desired, the programmer can transmit a
digital test tone 
(1007Ex, OdBM, sine wave) over the
selected 
Tl circuit. The tone can be verified by mon-
itoring the transmit audio port on the card’s dual ban-
tam jack.
Page 2-19 
						

							SPECIFICATIONSIssue 1, November 1994INTER-TELPRACTICESlMX/GMX 256 INSTALLATION 4% MAINTENANCE
- Error diagnostics: If desired; the programmer can
generate the current 
Tl error counts (by hour and by
day) for the selected card. The error counts can bedisplayed in a graphical or tabular format, printed
(stand-alone/remote only), or saved in a file for fu-
ture reference.
3.89The information that is programmed 
specifzc toeach 
circuir (i.e., each of the 24 channels) on the Tl
Card includes:
- Circuit type: Each individual circuit can be pro-
grammed 3s a loop start, ground start, DID, E&M, or
OPX trunk.
- Diital gain control: As with the other trunk cards,
should voice transmit or voice receive volume prob
lems occur, the programmer can adjust the receive
gain and/or the transmit gain (-15dB to 15dB) for in-
dividual 
Tl circuits.
- DTMF’ or dial-pulse signaliug: When the system isin the default configuration, all trunk circuits are
configured for DTMP signaling. If necessary, some
or all of the circuits can be reprogrammed for 
dial-
pulse signaling.
3.90The Tl circuits are assigned hardware address
numbers according to the card’s slot in the equipment
cabinet and the location of the circuit on the card. For
example, 
Tl circuit 6.21 is the 21st circuit on the 6th
card, a 
TlC, installed in the equipment cabinet.
3.91Special Tl cabling requirements: It is recom-
mended that special high-speed data cable with the fol-
lowing characteristics be used for all 
Tl installations:22 AWG
Individually shielded two-pair (or with the transmitand receive pairs run in separate cables or binder
&TOT4
ABAM or PIC (a level-3 cable designed specifically
for the T-carrier transmission rate)
Maximum capacitance of 
lSpF/ft.Maximum attenuation of 
5dB/lOOO ft. at 772kHx
and 
70“ F
NOTE: The programming prompts for 
LB0 attenua-
tion and DSX-1 line length assume that proper 
Tl cable(with the above characteristics) is 
being used. When
transmitting over shorter distances (e.g., when the near-est public network 
Tl repeater is less than 2000 feet
from the MDF), it may be possible to use standard two-
pair voice frequency cable instead; however, the pro-
grammer may have to compensate by selecting longer
LB0 distances or DSX-1 line lengths. Also, no matterwhich type of cable is used, the transmit and receive
pairs must be shielded from each other (or nm in sepa-
rate cables or binder groups).
3.92If the optional DB15 
corrector on the Tl Card is
used in place of the standard 
RJ48C jack, a flat, 2SAWG,
twisted-pair ribbon cable with a maximum capacitance
of 
16pF/ft. may be used for distances of up to 50 feet (see
page 3-20 for more information). For distances longerthan 50 feet, use the special high-speed data cable
described in paragraph 3.91.
Page 2-20 
						

							E!E=2imcwSTALLATION & MAINTENANCESPECIFICATIONSIssue 1, November 19944. STATION INSTRUMENTS
4.1A wide variety of station instruments can be used
on the 256 System. The combination of station instru-
ments depends on the number and type of station cardsinstalled.
4.2The system capacity for stations is as follows:
Total Station hstrnments256
Key-
I-Using Digital Keysets OnlyCL256-Using &Line Dual-M. AIMS OnlyO-256
I-UsingOther’QpeKeysetsOnlyO-128Attendant calDuter Consoles&128Single-Line Se&&240’Dss/BLFunits
I
-using Digital units onlycL200-using Analog units onlyO-50-
*At least one Kevset Card must be installed to urovide an atten-
dant (equipped kitlt a display keyset or an Am&ant ComputerConsole) to re4xive system alarm messages, program systemdata,andrecciveamqen&dCOrecaUs.Whenthesystemisin the default umtiguration, circuit 1.1 is designated as a keyset
and the primaxy attendant.
l *Analog Keysets, analog DWBIP Units, and Attendant Corn-
puter Consoles use separate KSC or KSCD citcnits. Therefore,
for each analog DSS/BLF Unit installed, one less analog key&or Attendant Computer Console may be installed. (A DWBLFUnitcannotbepro~edasthe”IT’circaitforan&linedual-circuit JhfX AIh4 keyset.)
NOTE: Since most systems will be installed with a vari-
ety of station and trunk cards and a variety of station in-
struments, the maximum station and trunk capacities
listed in this manual will rarely be reached.A.
IMX 256 KEYSETS
4.3Refer to page 3-71 for keyset installation instruc-
1 tions. The following digital and analog models are
available:
Il
0
0
0
a
0
0
0
Standard Digital Keysets (also referred to as Stan-
dard Digital Terminals)
- display and non-displayExecutive Digital 
Keysets (also referred to as
Executive Digital Terminals) - display only
24Line AlM Keysets (display only)
12-Line 
AIM Keysets (display only)
8-Line Dual-Circuit AIM 
Keysets (display only)
24Line Keysets (standard and display)
12-Line 
Keysets (standard and display)
8-Line 
Keysets (non-display only)
NOTE: With the proper software package, the Inter-Tel
GX station instruments can be installed on the system.
Refer to Appendix A in the back of the manual for com-
plete information.4.4For illustrations of the 
keysets (and other station
instruments), refer to the drawings beginning on page
2-33. The feature keys, speeddial keys, call keys, and
station programmable keys shown in the drawings are as
they appear when the system is in the default 
cotigura-
tion.4.5
The approximate dimensions of both the Standard
and Executive Digital 
Keysets are:Height 3.0 in. (7.6 cm.)
Width 7.5 in. (19.1 cm.)
Length 9.0 in. (22.9 cm.)
Weight 2.3 lb. (1.0 kg.)
4.6The IMX 12~line and 24-line keyset dimensions
are:Height 5.5 in. (14.0 cm.)
Width 9.0 in. (22.9 cm.)
Length 9.5 in. (24.1 cm.)
Weight 3.1 lb. (1.4 kg.)
4.7The lMX 8-line keyset dimensions are:Height 4.5 in. (11.4 cm.)
Width 6.5 in. (16.5 cm.)
Length 9.5 in. (24.1 cm.)
Weight 2.5 lb. (1.1 kg.)
4.8All keysets (except as noted) have the following
design features in their default configuration:
0
0
0
0
0
0
0l
0
0
12-key pushbutton keypad
Avariety of feature keys (some of which may be des-
ignated as user programmable)
IC/CO speed-dial (SD) keys with light-emitting
diode (LED) indicators (S-line keysets do not have
SD keys in the default configuration)
Four call keys with LED indicators for incoming call
access and indicationIntegrated speakerphone (digital 
keysets have
access to shared speakerphone resources)Ring and voice volume controls (digital and AIM
keysets have UP and DOWN keys for adjusting vol-
ume levels)
Slide-out directory card
Self-test feature (for testing 
keyset functions)
Hearing aid-compatible 
(HAC) handset
Reversible baseplate for wall mounting and revers-ible cradle hook for holding the handset on 
wall-
mounted keysets
I
I
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							SPECIFICATIONSIssue 1, November 1994INTEX-TELPRACTICESIMX/GMX 256 INSWTION & MAINTENANCE
Integrated Speakerphone
4.9A built-in, integrated speakerphone is standard in
all 
IMX analog keysets. All digital keysets have a speak-
er and a microphone for 
handsfree intercom reply, but
they do not have a true integrated speakerphone. How-
ever, the 
DSP(s) on the associated DISC can be used to
provide shared integrated speakerphone circuitry. (See
page 
4-40 for more information.)NOTE: If there are no DSP speakerphone resources
available when a digital keyset user attempts to use the
speakerphone, the MUTE key lights and display 
keysets
show NO SPKR 
AVAIL COME OFF HOOK The user
can only monitor the call and must lift the handset to
Speak.4.10 The integrated speakerphone allows users to
place and receive outside calls and intercom calls with-
out lifting the handset. Once a call is connected, the 
key-
set user may speak 
handsfree over the speakerphone or
lift the handset to speak privately. When using the hand-
set, the user may switch 
to the speakerphone by pressingthe SPKR key and replacing the handset. If enabled,
pages and/or background music may be broadcast over
the speaker when the phone is not being used.Liquid Crystal Display (LCD)
1 4.11All Executive Digital Keysets and all IMX AIM
keysets @I-line, ll-line, and S-line) come equipped
mwith LCDs. Standard Digital Keysets and standard Ih$X
24-line and ll-line keysets can be converted to display
sets by installing the appropriate LCD Unit (see RE-
PLACEMENT PARTS for the part number). Non-AM
g-line keysets cannot be equipped with displays.
4.12Each “display” 
keyset has a liquid crystal display(LCD) with two 
16character lines. The display helps
the user to process calls more efficiently and profession-
ally. There are display messages for date and time, num-bers dialed, call cost data, reminders, do-notdisturb,
forwarding, voice mail processing, incoming calls, sta-
tion and system status, system alarms, and program-ming. These displays are indicated throughout the
PEKWRES section of the manual.I
4.13Executive Digital Keysets have four additional
16-character display lines that are associated with the
eight menu selection keys that border them. The menudisplay changes to reflect the functions of the menukeys. Pressing the key next to the displayed option
selects that option. Refer to page 4-41 in IMMURES
for information about the available menu options.
Electret Circuitry
4.14All newer keysets and handsets have been de-
signed using “electret” microphone circuitry, rather
than the “dynamic” microphone circuitry used on many
previous Inter-Tel 
keyset models. Electret keysets and
handsets are not electrically compatible with dynamic
keysets and handsets.
4.15If a dynamic handset is attached to an 
electret
keyset, the handset transmit levels will be noticeably
lower. If an electret handset is attached to a dynamic
keyset, the handset will not transmit. (In both cases, nei-
ther the 
keyset nor the handset will be damaged.)
4.16
Electret keysets can be identified by the man-
ufacturer’s label on the bottom of the keyset. Electret
handsets can be identified by the “El” embossed in the
recess for the wall-mount hook (near the receiver).Optional Headsets
4.17A headset may be attached to any keyset by un-
plugging the handset from the handset jack on the base
of the 
keyset, plugging the headset into the handset jack,
and entering a feature code to enable the headset. The
SPKR key, which is used to turn the headset on and 
of&
is lit when placing and receiving calls and unlit when the
headset is not in use. The 
keysets are compatible with
industry-standard, four-conductor, modular headsets.The headsets can have 
electret or dynamic micro- 1
phones, as needed (or carbon-microphone headsets that
are connected to the 
keyset through an extemally-pow-
ered 
jackset, which makes the headset dynamiccom-
patible). Refer to page 3-77for installation iustructions.Optional Handset Amplifiers
4.18The typical handset amplifier is an external de-
vice that plugs into the 
keyset (where the handset is nor-
mally connected); the handset is then plugged into the
amplifier. Receiver voice volume is controlled by 
tum-
ing a thumbwheel (or similar control) located on the am-plifier. Such amplifiers are generally equipped with a
transformer that requires a 1lOVAC outlet. Refer to page
3-77 for installation instructions. AIM 
keysets do not
require handset amplifiers.
?.,’
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							INTER-TELPRACTICESSPECIFICATIONSlMX/GMX 256 INSTALLATION & MAINTENANCEIssue 1, November 1994
Optional Personal Computer Data Port Module
(PCDPM) for Diital Keysets
4.19For off-hook voice announce receive capability,
and to allow an optional digital 
DWBLFUnit and/or an
optional Modem Data Port Module to be installed, anydigital 
keyset may be equipped with an optional PC
Data Port Module (part no. 550.3014). See page 3-66
for instructions on installing the PC Data Port Module.
NOTE: 
PCDPMs require AC transformers when they
are connected to 
DSS/BLF Units only. PCDPMs do norrequire AC transformers when they are used for 
off-
hook voice announce only or have attached 
MDPMs.
For a diagram of AC transformer requirements, refer to
Figure 2-2 on page 2-24.Optional Modem Data Port Module 
(MDPMY) for
Digital 
Keysets4.20 Digital 
keysets equipped with PC Data Port
Modules may also be equipped with optional Modem
Data Port Modules (part no. 550.3015). The MDPM
contains a jack that can be used to connect a data device
(such as a Personal computer 
equ+d with a modem)
to the 
keyset. Each MDPM is powered by its own AC
transformer.
NOTE: 
MDPMs always require their own separate AC
transformers. For a diagram of AC transformer require-
ments, refer to Figure 2-2 on page 2-24.
4.21The data device attached to the 
MDPM must
have a direct-connection modem. The modem must be
external1 y powered (or capable of operating on 20mA of
loop current) and have an 
RJll CO interface. The data
device can be used by the associated 
keyset to com-
municate with remote data equipment over voice chan-
nels being used for CO or intercom calls. Refer to pages3-78 and 4-101 for installation and operation 
instmc-
tiOllS.Optional Data Port Module for 
IMX 12-Lime and
24-Lime Keysets4.22 
All IMX 12-line and 24line keysets may be
equipped with optional Data Port Modules (refer to RE-
PLACHMRNT PARTS for the part number). The mod-
ule contains a four-conductor, 
RJll modular jack that
can be used to connect 
either a data device (such as a
personal computer 
equ$ped with a modem) or a loud
ringing adapter 
(LRA) and an external signaling device
(such as a loud bell, horn, flashing light, etc.) to the 
key-
set. The Data Port Module is a source for 
20-26mA of
loop current (constant current source). Refer to page
3-78 for instructions on installing the optional Data PortModule.
4.23Specifications for modem-equipped data de-
vice: The data device must have a direct-connection
modem. The modem must be externally powered (or ca-
pable of operating on 20mAof loop current) and have an
RJll CO interface. The data device can be used with the
keyset to communicate with remote data equipment
over voice channels being used for CO or intercom calls.
Refer to pages 3-78 and 4-101 for installation and 
oper-
ation instructions.4.24 Specifications for loud ringing adapter
(I&A): An external LRAmay be connected to the Data
Port Module to provide a relay for controlling externalsignaling devices. The LRA is connected to the Data
Port Module, and the external signaling device is con-
nected to the LRA. Refer to page 3-80 for installation
instructions. Each time the 
keyset rings, the Data Port
Module provides 
20-26mA of loop current to the LRA.
This causes the 
LRA contacts to close and activates the
signaling device. The LRA is not affected by the ring
tone or the ringer volume of the 
keyset. The LRA must
be capable of operating on 20mA current (approximate-ly 
2OvDc).S-Line 
lMX AIM Keysets On Dual Ciiuits
4.25If desired, new 8-line IMX AIM keys& can be
installed two to a circuit using the new “dual-circuit”version 
Keyset Card @SC-D). (To install 8-line AIM
keysets one to a circuit, either the KSC or the KSC-D
can be used.) There are jumper straps on the back of the
8-line AIM keyset to select the baud rate (2400 baud for
two to a circuit; 1200 baud for one to a circuit) and to
select the circuit position (A or B), depending 
on how
the 
keyset’s circuit will be designated in database pro-
gramming.4.26 Each 
8-line AIM keyset is shipped with a stan-
dard (six-foot, three-pair) “flat” line cord for connecting
the 
keyset to its corresponding modular jack assembly.
For most installations, this flat line 
cord is more than ad-
equate. However, when 
8-line AIM keysets are installed
two to a circuit, low-level crosstalk between the two sta-
tions sharing the circuit may occur in certain situations.
This is because the wires in a flat line cord are parallel to
each other for long distances, thereby providing a sus-
ceptibility to audio bleedover. The level of crosstalk is
dependent on the voice volume of the users, the length
of the line cord, and the station cable loop length.
4.27To eliminate this low-level crosstalk, if neces-
sary, replace the flat line cord with a twisted-pair line
cord that has the following characteristics:l
Telcc orientation (rather than data)
0 26-gauge, stranded
l 
6to8twistsperfoot
Page 2-23 
						

							SPECIFICAlIONSIssue 1, November 1994INTER-TELPRACTICES
lMX/GMX 256 INSTALLATlON & MAINTENANCE
0Equipped with connectors designed specifically for
round, twisted-pair line cord
4.28Charcoal and 
grey twisted-pair line cords of vari-
ous lengths can be purchased 
from a local supply house
or directly 
from a cable distributor, such as:
AmericsnSources
Interstate Business Park 
#/806Fredericksburg, VA 22405
Phone: (703) 899-3777
FAX: (703) 371-4350
Pt. No.: 
LCM65OxL (Grey), LCM66OxL (Charcoal)
(whae x = kngth ia feet; e.g., LCM65O2.5L is a 25 ft. grcy cord)
-FIGURE 2-2.DIGITAL AC TRANSFORMER REQUIREMENTS
IEJ= AC transformer required
(for off-hook voice announce only)
NOTE: 
Digital DSS/BLF Units and MDPMs always require their own separate AC transformers. PCDPMs
require AC transformers when they are connected to 
DSS/BLF Units only. PCDPMs do not require AC trans-
formers when they are used for off-hook voice announce only or have attached MDPMs.
.-\:!,,j
. >,.‘.!. ’
Page 2-24