Mitel SX 200 DIGITAL Pabx Superset 3 Telephone Description Manual

							SECTION MITL9109-094-125-NATrunk Types
13.05 The E&M trunk module applies signals to the M lead and moni-
tors the E lead. In the on-hook condition, the Type 1 interface
grounds the M lead; an open presented to the E lead indicates idle, a
grounded E lead indicates an incoming call. In the off-hook condition,
the Type 1 interface applies -48 volts to the M lead; a ground sent to
the E lead indicates an incoming seizure.
Note:As of the date of issue of this Practice, Type 5 E&M signaling
is not approved for connection to the public network or for
use as an On-Premise Tie Trunk between systems.
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							Circuit Card Descriptions
14. MUSIC ON HOLD/PAGING MODULE
Brief Description
14.01 The Music on Hold/Paging module provides an input for music
on hold, a paging output and a relay to switch an external
paging amplifier. The module plugs into the Universal card. The Music
on Hold/Paging module has a power rating of 1.
Major Components
14.02Major components of the Music on Hold/Paging Module include:aaudio filter/amplitude limiter
lMite1 8961 filter/codec
lpaging driver amplifier
lpaging control relay.
Electrical Description
14.03 The music input is isolated by a transformer and has an imped-
ance of 600 ohms. The signal should be between 50 and 500
mVrms. High frequencies are attenuated and amplitude limiting is ap-
plied as required by FCC rules part 68. Amplitude limiting is applied
when the signal exceeds approximately 390 
mV rms.
14.04 The paging output is isolated by a transformer and has an
. impedance of less than 200 ohms. The output level into a 600
ohm load is typically -6 
dBm (388 mV rms).
14.05 The control relay contacts are rated as follows:
maximum switching voltage 90 Vrms
maximum carrying current 0.4 Arms
Note:This relay contact may be connected only to a secondary
circuit that has no direct connection to a primary circuit, and
receives its power from a transformer, converter, or equiv-
alent isolation device situated within the equipment.
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							SECTION MITL9109-094-125-NAPage 32 
						

							Circuit Card Descriptions
15. DID TRUNK CARDBrief Description15.01 The DID trunk card contains six l-way Direct Inward Dial cir-
cuits. It plugs into the digital peripheral bay. One-Way Direct
inward Dialing (DID) provides for direct access to PABX subscriber
lines from the public telephone network.
15.02 DID trunk cards can be used in any digital peripheral bay high
power (upper) slot. The maximum number of these cards is four
per bay. This provides a maximum of 24 ports per peripheral bay.
15.03 The card is 157.5 mm (6.2 in.) high and 366.4 mm (14.4 in.) long.
Major Components15.04 Major components in the DID Trunk Card are:
lMite1 8962 FilterKodec (one per trunk circuit)
0Feed Reversal relay (one per trunk circuit) Alarm LED.
Facilities15.05 The facilities 
provide,d by each trunk circuit are:
0Trunk activity LED
0Line protection
02-wire / 4-wire conversion (external to internal)
0Analog-to-Digital / Digital-to-Analog conversion (plaw)
0Immediate, Delay Dial or Wink Start supervision
0Direct Inward Dialing access to PABX subscriber lines
lConformity with the EIA loss level plan for plaw-compatible
PABXs in North America.
Operation15.06 A 
.trunk is idle if the resistance across Tip and Ring is 4000
ohms or more. In idle condition the PABX provides forward
battery feed to the line. The Tip is grounded and the Ring is at -48
Volts.
15.07 The CO initiates a call to the PABX by terminating Tip and Ring.
The supervision circuitry. detects the flow of loop current and
alerts the system software. The PABX signals it is ready to receive
dialing by briefly applying a battery reversal to the line. Ring is
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							SECTION MITL9109-094-125-NAgrounded and Tip is at -48 Volts. There are two types of controlled
address signaling: Delay Dial and Wink Start.
15.08 A Delay Dial signal must start no later than 150 ms after trunk
seizure. It is held until the PABX is ready to receive dialing. The
minimum hold time is 140 ms.
15.09 A Wink Start signal must start at least 100 ms after trunk
seizure. It is sent when the PABX is ready to receive dialing and,
can be held a maximum of 290 ms.
15.10 Where the CO does not provide controlled address signaling,
the PABX must be prepared to receive dialing 65 ms after trunk
seizure.
15.11 When called station or PABX attendant answers, the PABX
places battery reversal on the line for the duration of the call.
The trunk then returns to the idle state.
15.12 A trunk may be busied out by the system software. This pre-
sents an open circuit to the Tip and Ring of both the trunk and
trunk card circuit. The trunks default to the busy-out state if system
power fails.
15.13 Each circuit has a LED on the front panel which lights to in-
dicate the trunk is in use. A seventh LED at the bottom of the
panel lights to indicate a failure on the card.
Electrical Description
15.14 Line protection comprises high voltage varistors to energy
dump ground from Tip and Ring and fusible links incorporated
fin the battery feed resistors. EMI is controlled by inductors in series
with Tip and Ring.
15.15 The maximum loop resistance is 1800 ohms. The maximum loop
length is 5850 m (19,200 ft) when using 26 AWG wire, 15,240 m
(50,000 ft) when using 22 AWG wire.
15.16 The card circuitry performs 2-wire to 4-wire conversion, split-
ting the signal on the trunk into outgoing and incoming speech
paths. The analog signal coming from the trunk is converted to Pulse
Code Modulation (PCM); the signal to be sent to the trunk is converted
from PCM to analog audio. These conversions are performed by a 
Mite1
Codec chip.
Battery Feed Reversal and Busy-out for each trunk are controlled by
relays, as shown below.
ConditionRelay 1
Relay 2
Forward Feed (Idle)
ONOFFReverse Feed (Talk)
ONONPage 34 
						

							Circuit Card Descriptions
16. LWGS TRUNK CARD
Brief Description
16.01 The Loop Start/Ground Start trunk card mounts in any digital
bay and interfaces six trunk circuits to the system. The card is
158 mm high x 368 mm long (6.2 in. x 14.5 in.). Figure 16-1 illustrates
the card and the 
LUGS jumper.
Facilities
16.02 Facilities provided by the 
LWGS Trunk Card include:
l
Loop Start or Ground Start selectable by jumper
0M and MM signaling leads available
0Trunk activity indicated by LED (one per trunk)
aTransient suppression on Tip, Ring, and signaling leads Alarm
LED.Electrical Description
16.03 The Loop Start/Ground Start trunk card mounts in
bay and interfaces six trunk circuits to the system.
circuit is programmed as loop start or ground start by a
prior to installation.any digital
Each trunk
jumper clip
16.04 Each trunk has Tip and Ring leads and M and Ml
v1 leads for
additional signaling, if required. All leads are protected by varis-
tors against transients between line and ground. There are also varis-
tors between Tip and Ring and between M and MM. Each lead is in
series with an inductor near the edge connector to reduce elec-
tromagnetic interference 
(EMI).16.05 Each trunk has an LED on the front faceplate of the card that
lights to indicate the circuit is busy. An LED at the bottom of
the faceplate lights to indicate a failure on the card.
Operation
- Loop Start
16.06 To place an outgoing call, the trunk card places a termination
across tip and ring. The CO detects the current flow and re-
sponds with dial tone. Now the user may begin to dial.
16.07 The Trunk card recognizes an incoming call when it receives
ringing voltage or battery reversal from the CO. The Trunk card
will respond by placing a termination across Tip and Ring. The trunk is
released when the loop current is broken. This happens when the near
party goes on-hook or the line is physically broken.
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							SECTION MITLSI 09-094-l 25-NA
MARKED END
SHOWN FORLOOP START TRUNK
I
IIII
I
III *IIk
m--------+-------+--------
: *IIII a
IIIIIi *
ITTRUNK’ OTRUNK2II
II
(Figure 16-1 Loop Start/Ground Start Card and Jumper Location
Ic-TRUNK 2
W-TRUNK 3i
YRUNK 4‘&TRUNK 5
I
7684ElRlPage 36 
						

							Circuit Card Descriptions
Operation- Ground Start
16.08 To place an outgoing call, the Trunk card grounds the Ring lead.
The CO responds by grounding the Tip lead. The Trunk then
places a termination across Tip and Ring and ungrounds the Ring lead.
The CO then sends dial tone, indicating that it is ready to receive
dialing.
16.09 The Trunk card recognizes an incoming call when the CO
grounds the Tip lead. The CO may also send ringing voltage.
The Trunk card will respond by placing a termination across Tip and
Ring. The trunk is released when the loop current is broken. This
happens when either party goes on-hook or the line is physically
broken.
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							SECTION MITL9109-094-125-NAPage 38 
						

							Circuit Card Descriptions
17. ONS LINE CARD
WARNING
ANY CONNECTION OF THIS CARD TO AN OFF PREMISE APPLICA-
TION, AN OUT OF PLANT APPLICATION, OR TO ANY OTHER EXPOSED
PLANT APPLICATION MAY RESULT IN A SAFETY HAZARD, AND/OR
DEFECTIVE OPERATION, AND/OR EQUIPMENT DAMAGE.
General Description
17.01 The On-Premises (ONS) Line card interfaces standard subscrib-
er telephone sets to a PABX in the same building. It contains 12
line circuits and plugs into any digital bay.
17.02 The card is 158 mm high x 368 mm long (6.2 in. x 14.5 in.).
17.03 There are 13 LEDs on the front face of the card. The top 12 are
each connected to a line circuit and light to show that the
circuit is in use., The LED at the bottom of the panel lights to indicate
an alarm (failure) condition.
Facilities
17.04Each line circuit provides the following facilities:
lLine protection
aAnalog-to-Digital / Digital-to-Analog conversion (plaw)
lLine circuit status monitoring
aSignaling (ringing, message waiting).
Electrical Description
17.05 The following description applies to each line circuit.
17.06 Tip and Ring are each protected against transients by a 200 volt
varistor to ground. A bridge rectifier provides four protection
diodes for the line circuit transistors. The -28 volt line is protected by
a 35 volt transzorb.
17.07 The line circuit performs 2-wire to 4-wire conversion, splitting
the signal on the line into outgoing and incoming speech paths.
The analog signal coming from the telephone is converted to Pulse
Code Modulation (PCM); the signal to be sent to the telephone is
converted from PCM to analog audio. These conversions are per-
formed by a 
Mite1 Codec chip.
Page 39