Positron 7715-3 Operating and installation instructions

Standalone Power Supply Unit
48 V dc to -24 V dc, 7715-3
Description and Installation

DOCUMENT CONTROL INFORMATION
Document Part Number: 7715-24-03, Rev 4
Document Issue Number: 4
Publication Date: January 07, 2003
Document ID: (o01j1000.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
o01j1000TOC.fm
1. The Standalone Power Supply Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2. Hardware Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Technical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.1 Mechanical Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1.1 Wall Mount. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.1.2 Teleline Shelf Mount . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2 Electrical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5. Service and Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

(16 pages) Standalone Power Supply Unit, 48 Vdc to -24 Vdc 1
7715-3
o01j1001.fm
1. The Standalone Power Supply Unit
The Standalone Power Supply Unit, model 7715-3 converts floating 48 V dc
from a station battery to -24 V dc referenced to station ground. This large
capacity standalone power supply, can be used to power a fully loaded Three,
Five or Eight-card Shelf. For a view of the Standalone Power Supply Unit, refer
to Figure 1.
The installation kit consists of the Standalone Power Supply Unit, in a durable,
metal enclosure. The kit contains a Description and Installation document,
mounting platform, connecting cables, and mounting hardware.
Attention
This unit cannot be used in conjunction with any other -24 V dc power
supply of the Teleline product line, whether of the standalone or plug-in
variety. For a complete list of incompatible equipment, refer to Table 3.

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2 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
Figure 1 Model 7715-3
3-7/8"
MOUNTING TRAY
RIGHT SIDE VIEW
16-1/4"
FRONT VIEW
POSITRON # 7715-3 POWER
FAST-BLO
1.5 AMP
MOUNTING
TRAY
INPUT CABLE
9-2/3"
INPUT FUSE
ANCHORING BRACKET
OUTPUT CONNECTOR

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 3
7715-3
Its features include the following:
•The unit may be used with both the old and new generation multi-card
Teleline shelf.
•The unit supplies continuous -24 V dc at up to 2 A from a 48 V dc floating
station battery, without compromising its floating nature.
•The supply uses high-reliability solid state switching technology to perform
the DC to DC conversion.
•The unit’s input is protected against overvoltage transients.
•Two 1½amp input fast-blow fuses protect the power supply against ground
faults and the station battery against a malfunction of the supply. The fuse on
the line input wire is also accessible from the front panel.
•The unit is equipped with a current limiting circuit at its input to prevent an
excessive current surge upon connection of the station battery.
•The unit is equipped with a current limiter at the output for short circuit
protection.
•A green “Power On”LED located on the front panel indicates the presence
of -24 V dc output.

7715-3
4 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
2. Hardware Description
For the unit’s block diagram, refer to Figure 2.
Figure 2 Block Diagram
Overvoltage
Protection
RF Filter Rectifier/
Filter
Smooth
Charge
Circuit
Transformer
Solid
State
Switch
Voltage
Regulator
Timing
48 V dc in
-24 V dc out
(referenced to station ground)

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 5
7715-3
The following is a description of the elements of the Standalone Power Supply
Unit block diagram.
Overvoltage Protection
The Overvoltage Protection is supplied by metal oxide varistors (MOVs) in
metallic and longitudinal configuration that will blow the input fuses in case of
sustained overvoltage at the input.
Smooth Charge Circuit
The Smooth Charge Circuit is a current limiter which limits the charging current
on initial connection to the batteries.
RF Filter
The RF Filter prevents switching noise from the power supply being introduced
onto the power leads.
Solid State Switch
The Solid State Switch is the switching circuit of the switch mode power supply.
Transformer
The Transformer provides 1500 V isolation while stepping down the voltage for
the regulator.
Rectifier/Filter
The Rectifier/Filter circuit rectifies the switching current coming out of the
transformer and charges the capacitor of the filter to produce a DC voltage.
Voltage Regulator
The Voltage Regulator steps down the voltage out of the power supply to a
precise and steady -24 V dc.
Timing
Timing is handled by a timing feedback circuit that monitors the output voltage
and increases or decreases the pulse width of the switch to maintain a controlled
voltage before the regulator.

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6 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
3. Technical Specifications
For a listing of the unit’s electrical specifications, refer to Table 1. For a listing of
the unit’s physical specifications, refer to Table 2.
Table 1 Electrical Specifications (measured at 77°F or 25°C,
50% R.H.))
Table 2 Physical Specifications
Parameter Specifications
Input station voltage 42 to 56 V dc
Input power at full load 58 W
Nominal output voltage -24 V dc
Maximum output current 2.0 A
Maximum output power 48 W
Output ripple voltage 100 mVpp
Regulation, line <1.0%
Regulation, load <5.0%
Input/output isolation 1500 V @ 60 Hz for 1 minute
Parameter Specifications
Operating temperature range +32°F to +122°F (0°C to + 50°C)
Height 3.9”(9.9 cm)
Width 16.3”(41.4 cm)
Depth 9.7”(24.6 cm)
Weight 6.8 lbs (3.1 kg)

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 7
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4. Installation
This installation procedure assumes that the Three, Five or Eight-card Shelf
being used has already been mounted as per its installation instructions. For
further information, refer to the Description and Installation documentation for
the Three-card Shelf, model 751127, part number 924-010186-001,
Five-card Shelf, model 751112/1, part number 924-010199-001, or the
Eight-card Shelf, model 751109/13, part number 924-010040-001, respectively.
Caution
•Stand on a thick rubber mat and wear rubber gloves during the
installation procedure. 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 unit utilizes CMOS circuitry that can be damaged by static
electricity. The unit is not to be opened.
1. Verify that you are not using any equipment which is incompatible with the
Standalone Power Supply Unit. Do not use power supply 7715-3 with any
other plug-in or standalone -24 V dc power supply. For a listing of
incompatible equipment, refer to Table 3.
Table 3 Incompatible Equipment
Do Not Use Power Supply 7715-3 with the Following Equipment
A shelf containing one or more -24 V dc plug-in power supply cards
(the -24 V dc plug-in card must be permanently removed from the
shelf if a standalone -24 V dc supply is used)
751313
751316
751324
A shelf powered by any other -24V dc standalone supply 7715-2
7856-3

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8 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
2. Verify that you have the following customer supplied tools and hardware
which are required to install the unit:
•Cable from station batteries
•Center punch
•Electric drill with a 5/32”diameter bit
•7/16”hex wrench
•Phillips screwdriver
•Cable clamps and mounting hardware for routing cables exterior to the shelf
(quantity determined by the cable lengths involved).
3. Unpack the Standalone Power Supply Unit and its installation hardware
from its protective box.
4. Check the contents of your Standalone Power Supply Unit. For a listing of
the items included in the kit, refer to Table 4.
Table 4 Model 7715-3 Kit Contents
5. Confirm that the unit is a Standalone Power Supply Unit by identifying the
model number on its faceplate.
Items Included Qty Part Number
Standalone Power Supply Unit 1 244-040025-401
Description and Installation document 1 7715-24-03
Mounting platform 1 7856-02-09
6.5’power supply input cable (pre-wired to supply) 1 207-010091-401
6.5’power supply output cable 1 207-010087-401
Anchoring brackets 2 7856-02-07
Hex screws with washers (#14A, 1”long) 3 724-990000-011
Mounting bolts (1/2”long) 2 724-020001-029
Washers #10 flat 2 738-990110-005
Lock washers #10 2 738-990010-005

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 9
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4.1 Mechanical Installation
The power supply unit can be installed on a self-supporting wall-mounted tray, or
directly on the Teleline shelf. For an illustration of its installation, refer to Figure
3.
Figure 3 Model 7715-3 Installation
MOUNTING TRAY
ANCHORING BRACKET

7715-3
10 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
4.1.1 Wall Mount
1. Using the mounting tray as a template, position it against the desired
location (above or beside the shelf) and drill three, 5/32”diameter holes
into the 1”plywood surface.
2. Fasten the tray to the wall using the three, #14A screws and washers
provided.
3. Align the holes on the left side of the power supply enclosure with those on
the left side of the mounting tray. Use the two, 1/2”bolts and washers to
attach the two parts together.
4.1.2 Teleline Shelf Mount
1. Attach an anchoring bracket to each side of the power supply enclosure.
2. Position the power supply on the Teleline shelf, against the wall. Anchor the
unit in place by fastening the brackets to the wall.

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 11
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4.2 Electrical Installation
Caution
The station and Central Office (CO) cables should be kept at least six inches
apart upon wiring in order to prevent an electric arc between the two in the
event of damage to, or degradation of, their insulation.
1. Route the station battery cables to the power supply input cable. For a
listing of the Power Supply Unit’s input connections, refer to Table 5.
Table 5 Power Supply Unit Input Connections
2. Connect the power supply output to the shelf. For a Five or Eight-card
Shelf, this may be accomplished via the Station side cable or by using a
separate power cable. For a Three-card Shelf, the only entry is through the
Station side cable. For a listing of the Power Supply Unit’s output
connections, refer to Table 6.
Table 6 Power Supply Unit Output Connections
Station Power Supply Input
48 V dc battery, negative pole Red
48 V dc battery, positive pole Black
Station ground White
Power Supply Output Shelf Terminal Designation
Black GND
White -24V

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12 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
3. Ensure that there are no excess wires dangling into the isolation gap
between the Station and CO side circuits. Then close and secure the shelf
cover with the captive screws.
4. Verify that you obtain -24 V inside the shelf.
Note
Blown fuses are the only circuit components to be replaced by customer
maintenance personnel. Contact Positron should any other maintenance be
required.

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 13
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5. Service and Support
Technical Customer Support
Positron is committed to providing excellent ongoing technical support to its
customers. A team of specialists is always available at our Technical Support
Center in Montreal for either telephone consultations or on-site visits, to assist
Field Technical personnel in the maintenance and troubleshooting of Positron
equipment. During normal business hours, (8:30 a.m to 5:00 p.m. EST), any one
of our Technical Customer Support (TCS) staff may be reached by dialing
1-888-577-5254 from anywhere in the continental United States or from Canada.
Customers outside North America should dial 1-514-345-2200. Staff may also be
contacted via fax at 514-345-2271 or e-mail at [email protected].
Positron TCS staff are available to provide technical assistance and/or to
supervise the installation of Positron equipment. Assistance in the planning,
configuration, and implementation of the installation will be provided as
requested. Arrangements and pricing information regarding field assistance may
be obtained by contacting the Technical Customer Support department. Please
contact Positron for scheduling at least four weeks prior to the actual requested
visit date.
Customer Training
Positron offers full customer training courses, as requested. Seminars are also
available on High Voltage Interface (HVI). For more information, contact a
customer representative by dialing 1-888-577-5254 or use our e-mail address,
[email protected]c.ca.
Warranty
Positron warrants that all equipment shall perform in accordance with Positron’s
specifications. The warranty remains valid for five (5) years from the date of
shipment. The warranty will be honored provided that the equipment has not
been abused and provided that the equipment has been installed and used in
accordance with Positron’s installation instructions and specifications. The
warranty fully covers workmanship, materials and labor.
This warranty is in lieu of all other warranties, whether expressed or implied,
including warranties of merchantability and fitness for a particular purpose.
Positron guarantees that all equipment shall perform in accordance with
Positron’s specifications. Positron disclaims any warranty that Positron

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14 Standalone Power Supply Unit, 48 Vdc to -24 Vdc
equipment will meet customer requirements beyond the product specification.
Positron disclaims any warranty that operations will be uninterrupted or error
free.
Repair Service
Positron Inc. offers repair services by which customers can count on timely and
quality repairs, regardless of customer location.
All warranty repairs are performed at no cost. Positron reserves the right to repair
or replace any equipment which has been found to be defective.
For information about out-of-warranty repairs, contact Positron’s Repair
department at 1-800-661-4911 (from anywhere in the continental United States
or from Canada) or dial 514-345-2228. Due to the varied nature of repairs, no
one time frame for turnaround can be guaranteed. However, average turnaround
time is two weeks from date of receipt. In emergency situations, special
arrangements can be made by contacting our Repair department. All repaired
items are warranted for a period of 90 days. Bulk repairs (more than five items)
will require additional processing time, therefore, please take this into
consideration when requesting a Return Material Authorization (RMA) number.
Before returning any items to Positron for repair, warranty repair or replacement,
call the Repair department to obtain an RMA number. Parts returned without
RMA numbers cannot be accepted. The RMA number must always be clearly
marked on all boxes and crates and on all shipping documents.
Items under warranty are to be shipped prepaid to Positron and will be returned
prepaid to the customer. Items that are not under warranty are to be shipped
prepaid to Positron and will be returned prepaid with freight charges included on
the invoice. Positron cannot accept items shipped collect. A purchase order
number is required for all repairs.
To accelerate the repair process, whenever possible, customers should include a
report detailing the reason for return with the unit(s) being returned. Also, please
include the name and phone number of a person who can be contacted should our
Repair department need further information.
When packing items being returned for repair, please ensure that the item(s) is
properly packed to avoid further damage. Teleline Isolator cards should never be
shipped while installed in a shelf; this will cause damage and will almost
invariably extend the repair period.

Standalone Power Supply Unit, 48 Vdc to -24 Vdc 15
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Ordering Information
Positron’s Teleline equipment can be ordered by telephone, facsimile, or by mail.
All orders should be directed to the Positron Inside Sales department. Ordering
by telephone, or facsimile will eliminate any delays arising from postal services.
However, a hard copy purchase order is required as a confirmation. In addition to
the model numbers of the items being ordered, the following information is
required:
•Company name, contact name and telephone number
•Purchase order number
•“Ship To”address
•“Bill To”address
•Date required on site
All orders must be followed by a confirming order. Equipment will not be
shipped until such confirmation is received.
For a list of our contact information, refer to Table 7.
Table 7 Positron Contact Information
Address Positron Inc.
5101 Buchan St.
Montreal, Quebec, Canada
H4P 2R9
Main telephone number 514-345-2200
Customer Service department telephone
number
514-345-2200, 1-888-577-5254
General e-mail address [e-mail]
Customer Service department fax number 514-345-2271
TCS department toll-free number 1-888-577-5254
TCS department fax number 514-345-2271
TCS department e-mail address [e-mail]
Repair department telephone numbers 514-345-2228 or 1-800-661-4911
Customer representative e-mail address [e-mail]