GAI-Tronics 12600-002 User Manual

Pub. 42004-433C

GAI-TRONICS® CORPORATION

A HUBBELL COMPANY

Model 12600-002 and 12600-40x

Line Current Boost Cir cuit Assemblies

Confidential ity Notice

This manual is provided solely as an operational, installation, and maintenance guide and contains
sensitive business and technical information that is confidential and proprietary to GAI-Tronics.
GAI-Tronics retains all intellectual property and other rights in or to the information contained herein,
and such information may only be used in connection with the operation of your GAI-Tronics product or
system. This manual may not be disclosed in any form, in whole or in part, directly or indirectly, to any
third party.

General Information

This manual covers the following models of the GAI-Tronics Line Current Boost Circuit Assemblies:

Model Description

12600-002 Single Channel Line Current Boost Circuit
12600-401 4-Channel, DC-powered Line Current Boost Circuit
12600-402 8-Channel, DC-powered Line Current Boost Circuit
12600-403 4-Channel, AC-powered Line Current Boost Circuit
12600-404 8-Channel, AC-powered Line Current Boost Circuit

Telephone and PBX lines typically provide 20–35 mA or less line current to analog telephone
instruments. Several devices, including GAI-Tronics’ line of RED ALERT
require additional line current to drive speakers, power optical coupling devices, and electronic devices
such as microprocessors. The additional line current provided by the LCBC provides sufficient line
current for a substantial increase in audio power to
the emergency telephone speaker.

The GAI-Tronics Line Current
Boost Circuit (LCBC)
Assemblies are designed to
augment available line current
to an analog 2-wire bridged
ringing telephone line. They are
designed specifically to provide
an additional 30 mA line current
to a GAI-Tronics line-powered
emergency telephone.

®

emergency telephones,

Operation

The LCBC is designed to be installed anywhere
along the telephone line, preferably at a main or
intermediate distribution location. A CMOS
differential amplifier and two threshold compactors
are used to monitor the dc voltage across the phone
line (tip and ring).

Figure 1. Model 12600-002

GAI-Tronics Corporation 400 E. Wyomissing Ave. Mohnton, PA 19540 USA

610-777-1374  800-492-1212  Fax: [phone]

V

ISIT WWW.GAI-TRONICS.COM FOR PRODUCT LITERATURE AND MANUALS

Pub. 42004-433C

Model 12600-002 and 12600-40x Line Current Boost Circuit Assemblies Page: 2 of 5

When the dc voltage between tip and ring falls below 15 V dc, indicating an off-hook condition on the
line, the LCBC automatically adds 30 mA current to the available line current. If the PBX provides 20
mA line current, the LCBC adds an additional line current of 30 mA for a total of 50 mA available to
drive speakers and other devices.

When the device connected to the line is placed on-hook (dc line voltage greater than 20 V), the LCBC
automatically disconnects the 30 mA supplemental line current. The LCBC is transparent to incoming
ring signals allowing operation on a 2-wire bridged ringing configuration.

CHANNEL 1 CHANNEL 2 CHANNEL 3 CHANNEL 4 CHANNEL 5 CHANNEL 6 CHANNEL 7 CHANNEL 8

Figure 2. Front Views of Model 12600-402/404 8-Channel LCBC Assemblies

OTE: Model 12600-401/403 4-Channel LCBC Assemblies contain a blank panel on the right side.

N

48 VDC +/-20%

Figure 3. Rear Views of Models 12600-401/402 DC-Powered (top) and Models 12600-403/404

AC-Powered LCBC (bottom) Assemblies

P ABX Interface Requirements

Minimum loop current: 8 mA dc (LCBC disconnected)
Maximum recommended loop current: 40 mA dc (LCBC disconnected)
Ringer requirements: Type B ringer

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