American Fibertek MT-926C User Manual

10/02/2012 JPK

Instruction Manual

MT-926C

Two Channel Video Transmitter

With One Bi-Directional Multi-Protocol Data

Channel And

One Bi-Directional Contact Closure Channel

Table of Contents

Functional Description................................................................................. 3

Installation ................................................................................................... 3

Power Source.............................................................................................. 3

Power Connection ....................................................................................... 4

Fiber Connection ......................................................................................... 4

Video Input Connections ............................................................................. 4

Data Input / Output Connections ................................................................. 4

Typical System Data Connections............................................................... 5

Contact Closure Input / Output Connections............................................... 5

Data Configuration Switches ....................................................................... 5

Data Termination And Offset Bias Switches................................................ 6

RS485 Data Termination And Offset Bias................................................... 6

MT-926C Status LED Indicators..................................................................7

Warranty and Service Information............................................................... 8

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INSTALLATION AND OPERATION INSTRUCTIONS

INTRODUCTION

Thank you for purchasing your American Fibertek Series 926C multimode two channel video
multiplexer with bi-directional multi-protocol data and contact closure. Please take a few minutes to
read these installation instructions in order to obtain the maximum performance from this product.

FUNCTIONAL DESCRIPTION

The MT-926C operates as half of a transmitter / receiver pair for the digital transmission of two
simultaneous NTSC or PAL video signals along with one channel of field configurable bi-directional
data and one channel of bi-directional contact closure over one multimode fiber optic cable. The data
channel may be configured as RS485 data, RS422 data, RS232 data, or Manchester data. The RS485
channel may be configured for 2-wire (half duplex) or 4-wire (full duplex) with or without biasing. Switch
selectable internal 120 ohm terminations are available for RS422 or RS485 data.

NOTE: This unit is shipped with Data Channel 1 in the RS485 4-wire configuration. For other
configurations, please refer to the DATA CONFIGURATION section for changes to the default
switch settings. Data Channel 2 is set for contact closure and can not be reconfigured.

NOTE: This unit is shipped with data terminations off and data bias off for Data Channel 1. For
other configurations, please refer to the DATA TERMINATION / BIAS section for changes to the
default switch settings.

The MT-926C multiplexes two video input signals along with one data signal and one contact closure
signal into a high speed serial data stream. This serial data stream modulates a laser at 1310nm
wavelength. The MT-926C also detects and demultiplexes a return optical serial data stream containing
one data signal and one contact closure signal at 1550nm wavelength.

This unit is contained in a rugged aluminum housing with internal dc voltage regulation. The detachable
terminal blocks and LED indicators provide for easy installation and monitoring of video, data, and
optical power.

The MT-926C is designed for mounting as a modular stand alone unit. For a rack mounted version
please see the RT-926C.

INSTALLATION

THIS INSTALLATION SHOULD BE MADE BY A QUALIFIED SERVICE PERSON AND SHOULD
CONFORM TO THE NATIONAL ELECTRICAL CODE, ANSI/NFPA 70 AND LOCAL CODES.

Mount the unit to a secure surface using #8 (3mm) hardware in four places. See the drawing on the
next page for mounting dimensions. Be sure to allow sufficient room for the required minimum bend
radius of the fiber cable used.

POWER SOURCE

THIS PRODUCT SHALL BE POWERED BY A LISTED CLASS 2 POWER SUPPLY ONLY.
This unit requires a +12VDC power source with a current rating of 1.25 amps for proper operation. The

DC input is diode protected. In the USA and in Canada an American Fibertek PS-12D is supplied with
this unit. The negative side of the power input is directly connected to ground. ANSI/NFPA 70 Class 2
wiring is recommended.

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