Positron Teleline Isolator 7501-16A Operating and installation instructions

Plug-in OPX Card
7501-16A, B and C
Description and Installation

DOCUMENT CONTROL INFORMATION
Document Part Number: 7501-24-16, Rev. 7
Project Level: 7
Publication Date: January 09, 2003
Document ID: o02i1100.fm
CONFIDENTIALITY NOTICE
The information contained in this document is the property of Positron Inc. Except as specifically
authorized in writing by Positron Inc., the holder of this document: 1) shall keep all information
contained herein confidential and shall protect same in whole or in part from the disclosure and
dissemination to all third parties, and 2) shall use same for operating and maintenance purposes only.
DISCLAIMER NOTICE
Although Positron Inc. has made every effort to ensure the accuracy of the information contained
herein, this document is subject to change without notice.
TECHNICAL CUSTOMER SUPPORT
Should a problem arise, contact your customer support department. If the problem cannot be resolved
by your support department or if you have any questions, contact Positron’s Technical Customer
Support department at 1-888-577-5254.
© 2003 Positron Inc.
Teleline Isolator is a registered trademark of Positron Inc.
Product names, other than Positron’s, mentioned herein may be trademarks and/or registered trademarks
of their respective companies.

Contents i
o02i1100TOC.fm
1. The Plug-in OPX Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2. Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Hardware Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Technical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6. Service and Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

(22 pages) Plug-in OPX Card 1
7501-16A, B, C
o02i1101.fm
1. The Plug-in OPX Card
The Plug-in Off Premise Extension (OPX) Card is used to provide high voltage
isolation for a wide variety of telephone voice grade applications involving the
bi-directional transmission of AC and DC voltage.The unit is a plug-in card
designed for use with the Teleline Isolator multi-card shelf. It is available in three
options, as listed below:
•Model 7501-16A is designed for a floating 130 V dc source.
•Model 7501-16B is designed for a -24 V dc source referenced to station
ground.
•Model 7501-16C is designed for a -48 V dc source, also referenced to station
ground.
Its features include the following:
•The card may be used with both the old and the new generation Three, Five
and Eight-card Teleline Shelf.
•The OPX Card is completely bi-directional to all loop signalling, i.e. line
voltages can originate from either Station or Central Office (CO) side loops.
Bi-directional modulator/demodulators are used to realize a circuit which
behaves as an ideal 1:1 isolation device.
•Varistors provide transient voltage protection to the isolation device.
•The OPX Card provides low loss, full duplex DC to voice band
communication.
•The OPX Card transmits on/off-hook, dial pulses or touch tone signalling,
ringing, polarity reversals, AC and DC voltage and current levels.
•Impedances applied to either side of the card are reflected to the opposite
side.
Model variations A, B, and C are all visually similar. For a view of the Plug-in
OPX Card, refer to Figure 1.

7501-16A, B, C
2 Plug-in OPX Card
Figure 1 Model 7501-16A Component Layout (Only Major
Components Shown)
POSITRON
7501-16A
O.P.X MODULE
7-7/16"
12"
STATION SIDE
CO SIDE
2"
ISOLATION
GAP
4¼"
ISOLATION
TRANSFORMER
ISOLATION
TRANSFORMER
mA
C.O.
mA
STATION
EQUALIZE
mA
MONITORING JACK
MONITORING JACK
TRIM
POTS
NOTE: The faceplates of models 7501-16B and C will bear their respective model
numbers, instead of 7501-16A. The rest of the units are visually similar.
1
2
3
4
5
6
GROUND
-24 V dc
TIP (+)
RING (-)
-48 Vdc from shelf
PCB +130 V dc (RU GEN from shelf)
TIP (+)
RING (-)
RMT GND

Plug-in OPX Card 3
7501-16A, B, C
2. Applications
The applications of the OPX Card include the following:
•OPX. For an illustration of this application, refer to Figure 3.
•Direct Inward Dial (DID) loop start. For an illustration of this application,
refer to Figure 4.
•Automatic ring down. For an illustration of this application, refer to Figure
5.
•Radio keying. For an illustration of this application, refer to Figure 6.
•Loop start telephone
•Call waiting pulse
•Forward disconnect
•Caller ID
•Coin telephone (two cards required)
•Simplex continuity when used with four-wire DX signalling
•Fax and dial-up “smart”modems (up to 56.6 Kb modem, speed of 45.3 Kb/s
if line permits)
Refer to Figure 2 for applications.

7501-16A, B, C
4 Plug-in OPX Card
Figure 2 High Voltage Interface Applications
Plug-in OPX Card
Model 7501-16A, B or C
Communications Cable
300 Volt
Point
300 Volt
Point
300 Volt
Point
Zone of Influence
Metal
Conduit
PVC
Conduit
Lightning
Arrestor
CENTRAL OFFICE
HIGH VOLTAGE INTERFACE
SUBSTATION
Fax or Modem
Telephone, PBX

Plug-in OPX Card 5
7501-16A, B, C
Figure 3 Typical Off Premises Extension (OPX) Application
STATION A
STATION B
ISOLATION
CARD
MODEL 751321
OPX CARD
PBX
EXT.
*Note: The isolation card is only required if a ground potential rise is
possible at the remote site (Station B). If Station B is not a power plant,
the telephone card can be omitted.
A
B

7501-16A, B, C
6 Plug-in OPX Card
Figure 4 Typical Direct Inward Dial (DID) Application
CENTRAL OFFICE
SUBSTATION
OPX CARD
PBX
Ring Tip

Plug-in OPX Card 7
7501-16A, B, C
Figure 5 Typical Ring Down Application
0
1
STATION A
OPX CARD
RING
GENERATOR
RING
GENERATOR
STATION B
OPX CARD

7501-16A, B, C
8 Plug-in OPX Card
Figure 6 Typical Radio Keying Application
SUBSTATION
OPX CARD
RADIO

Plug-in OPX Card 9
7501-16A, B, C
3. Hardware Description
The OPX Card is comprised of two sides. The Station side is located on the upper
portion of the card and the CO side is located on the lower portion of the card.
The Station side is separated from the CO side by the isolation transformers
which create a 4¼inch isolation gap. For the card’s block diagram, refer to
Figure 7.
Figure 7 Block Diagram
STATION SIDE
CO SIDE
ISOLATION GAP
ISOLATION
TRANSFORMER
ISOLATION
TRANSFORMER
TRANSIENT
TRANSIENT
TEST JACK
TEST JACK
T
T
R
R
PROTECTION
PROTECTION
MOSFET
TIMING
VOLTAGE
INPUT
NEGATIVE
SWITCHES
MOSFET
SWITCHES
IMPEDANCE
POWER
SUPPLY

7501-16A, B, C
10 Plug-in OPX Card
The following is a description of the elements of the OPX Card block diagram.
Transient Protection Blocks
The Transient Protection Blocks each consist of a varistor, and are designed to
protect their respective circuitry (Station or CO side) from transients.
Timing Block
The Timing Block consists of a crystal oscillator which provides the switching
frequency for the isolation devices.
MOSFET Switches
The metal oxide semiconductor field effect transistor (MOSFET) Switches are
synchronized together to ensure proper transfer of signals.
Negative Impedance Block
The Negative Impedance Block compensates for any signal losses incurred by
the isolation devices.
Isolation Transformers
The two Isolation Transformers are specifically designed and manufactured for
low-loss signal transmission, while providing the high dielectric strength
required for their intended use. They provide the 4¼inch isolation gap for the
card.
Test Jacks
The module faceplate also features two Test Jacks for use in the calibration
procedures described later in the Installation section of this document. Insertion
of a phono plug into these jacks permits the Station and CO side loop currents to
be monitored, and is an essential part of the maintenance and calibration routine
for a pilot wire system.
Power Supply Assembly
The Power Supply Assembly converts the station voltage to a level suitable for
the Station side of the card. Each DC Trip/DC Pilot Wire module variation is
designed for use with a specific station supply. The variations are as follows:
•Model 7501-16A operates from a 130 V dc station battery.
•Model 7501-16B operates from a -24 V dc power supply.
•Model 7501-16C operates from a -48 V dc power supply.

Plug-in OPX Card 11
7501-16A, B, C
4. Technical Specifications
For a listing of the card’s electrical specifications, refer to Table 1. For a listing of
the card’s physical specifications, refer to Table 2.
Table 1 Electrical Specifications (measured at 77°F or 25°C,
50% R.H.)
Parameter Specifications
7501-16A 7501-16B 7501-16C
ISOLATION DATA
Isolation resistance 100 000 MΩ100 000 MΩ100 000 MΩ
Metallic surge 3 kV max 3 kV max 3 kV max
Insulation voltage 30 kVrms (42 kV
peak)
30 kVrms (42 kV
peak)
30 kVrms (42 kV
peak)
SUPPLY VOLTAGE Floating: 105 to
150 V dc
Grounded: -21 to
-27 V dc
Grounded: -42 to
-56 V dc
SUPPLY CURRENT 55 mA maximum 350 mA
maximum
125 mA
maximum
POWER DISSIPATION
INSIDE SHELF
6.2 W maximum 8.5 W maximum 6 W maximum
MAXIMUM VOLTAGE TIP
TO RING
±150 V dc ±150 V dc ±150 V dc
MAXIMUM LOOP CURRENT ±100 mA
continuous
±100 mA
continuous
±100 mA
continuous
MAXIMUM LOOP POWER 5W 5W 5W
RESPONSE TIME (subscriber
to line, or line to subscriber)
<1 ms <1 ms <1 ms
SERIES RESISTANCE Series resistance
of 25Ωis added
to the telephone
loop.
Series resistance
of 25Ωis added
to the telephone
loop.
Series resistance
of 25Ωis added
to the telephone
loop.

7501-16A, B, C
12 Plug-in OPX Card
IMPEDANCE REFLECTION Impedances on
either side appear
on the opposite
side multiplied
by 90% to 110%
within the pass
band.
Impedances on
either side appear
on the opposite
side multiplied
by 90% to 110%
within the pass
band.
Impedances on
either side appear
on the opposite
side multiplied
by 90% to 110%
within the pass
band.
ON-HOOK DATA
Terminal resistance ≥200 KΩat
±100 V dc
≥200 KΩat
±100 V dc
≥200 KΩat
±100 V dc
OFF-HOOK DATA (40 mA dc)
Longitudinal balance (CO
Side)
>80 dB @ 60 Hz;
>56 dB @ 4 kHz
>80 dB @ 60 Hz;
>56 dB @ 4 kHz
>80 dB @ 60 Hz;
>56 dB @ 4 kHz
Crosstalk with adjacent card Betterthan-77dB
from 300 to 3400
Hz measured at
+10 dBm
Better than -77dB
from 300 to 3400
Hz measured at
+10 dBm
Better than -77dB
from 300 to 3400
Hz measured at
+10 dBm
Dial pulse distortion <1% measured at
14 mA threshold
(output duty
cycle with
respect to input
duty cycle)
<1% measured at
14 mA threshold
(output duty
cycle with
respect to input
duty cycle)
<1% measured at
14 mA threshold
(output duty
cycle with
respect to input
duty cycle)
NOISE
Impulse noise (both sides) Less than 1 count
in 30 minutes
above 48 dBrnc
Less than 1 count
in 30 minutes
above 48 dBrnc
Less than 1 count
in 30 minutes
above 48 dBrnc
Phase jitter (4-300 Hz) <0.5°<0.5°<0.5°
Message circuitnoise (quiet
termination)
<30 dBrnc <30 dBrnc <30 dBrnc
S/N ratio (C message filter) 50 dB at 0 dBm 50 dB at 0 dBm 50 dB at 0 dBm
SIGNAL
Bandwidth (-3 dB) 200 to 4 kHz 200 to 4 kHz 200 to 4 kHz
Parameter Specifications

Plug-in OPX Card 13
7501-16A, B, C
Table 2 Physical Specifications Model 7501-16A, B and C
Parameter Specifications
Operating temperature range +32°F to +122°F (0°C to 50°C)
Relative humidity 95% (non-condensing)
Height 12”(30.48 cm)
Width 2”(5.08 cm)
Depth 7-7/16”(18.89 cm)
Weight 3.488 lbs (1.582 kg)

7501-16A, B, C
14 Plug-in OPX Card
5. Installation
The OPX Card plugs into any slot of the Teleline Three, Five or Eight-card Shelf.
However, the card must be installed into the slot which has been pre-wired
according to the installation diagram of the specific shelf.
To view the Ground Start Coin Circuit using two 7501-16 cards, refer to Figure 8.
Figure 8 Ground Start Coin Circuit Using Two 7501-16 Cards
Note
1. Type 7501-16 cards can be powered with either -24 V, -48 V or
130 V dc; the suffix A, B or C specifies the operating voltage the
card is designed for.
2. Two cards are required per coin circuit.
3. Use in adjacent slots where possible.
4. You cannot use cards powered by 130 V dc in the same shelf as
7501-04 cards that require a ringing generator (RUGEN) as the
130V and the RUGEN share the same pin connection.

Plug-in OPX Card 15
7501-16A, B, C
To view the OPX trunk using single 7501-16 card, refer to Figure 9.
Figure 9 OPX Trunk Using Single 7501-16 Card
Note
1. Type 7501-16 cards can be powered with either -24V, -48V or
130 V dc; the suffix A, B or C specifies the operating voltage the
card is designed for.
2. You cannot use cards powered by 130 V dc in the same shelf as
7501-04 cards that require a ringing generator (RUGEN) as the
130V and the RUGEN share the same pin connection.
3. This card may be used for DID trunks where the PBX supplies the
loop battery.
4. This card can substitute for a 751311 type card when: 48 V dc
station side loop power, Caller ID, and/or Forward Disconnect
operations are required.

7501-16A, B, C
16 Plug-in OPX Card
Caution
•Stand on a thick rubber mat and wear rubber gloves during the
installation. It is preferable to perform these procedures on a clear dry
day when a Ground Potential Rise (GPR) or transients are less likely to
occur.
•This card utilizes CMOS circuitry that can be damaged by static
electricity. Observe normal CMOS handling procedures to avoid static
discharge. Manipulate the card exclusively by the faceplate to prevent
any damage to the card and to limit the possibility of electric shock.
When moving the card, carry it in an ESD safe container or the antistatic
bag, provided with the card. Failure to follow ESD precautions may
void the warranty. For further information concerning ESD precautions,
contact Positron’s Customer Support department.
•The remote ground must be brought in on a separate pair. Do not use the
cable sheath. Do not connect remote ground to station ground.
•The 130 V dc supply required by a model 7501-16A is connected
between the RU GEN (+) and the -48 V dc (-) pairs of the station cable
of the Teleline shelf. These conductors are floating with respect to
ground. The station ground terminal of the shelf must be connected to
station ground to create a path for leakage currents. This connection in
no way compromises the floating nature of the station batteries.
Danger
The “mA CO”jack on the module faceplate is connected to the CO side. If a
ground potential rise should occur, the potential difference between station
ground and cables and equipment connected to the CO jack can be very high.