User Manual
CBM Optical Isolation Patch Panel





Version 2.0
October, 2000











CBM of America warrants that its equipment is free from defects in materials and workmanship. The warranty period is one year from the date of shipment. CBM of America's obligation under this warranty is limited to the repair or replacement of the defective equipment provided it is returned to CBM, shipping prepaid, within a reasonable period of time. This warranty shall not apply to equipment that has been subject to accident, misuse, alterations, or repairs not made or authorized by CBM.

This publication and the equipment it describes contain proprietary information. No part of this document may be copied or reproduced in any form without permission from CBM of America. The information in this document is subject to change without notice. CBM of America assumes no responsibility for damages resulting from the use of this document, including but not limited to, lost revenue, lost data, or other damages. If you have any comments or suggestions regarding this document please e-mail or call 800-881-8202.

This manual describes how to install and configure the CBM Optical Isolation Patch Panel. This document is intended for use by trained technicians and installers and assumes a working knowledge of central office procedures and protocols.

The information contained in this document is arranged in two parts:

  • Product Overview provides a physical description of the Optical Isolation Patch Panel and it's associated features.
  • Installation and Operation details the necessary procedures required to install and operate the Optical Isolation Patch Panel.

Antistatic Precautions
Electrostatic discharge ( ESD ) results from the buildup of static electricity and can cause damage to electronic components. ESD precautionary practices are required when installing, configuring, or repairing the Optical Isolation Patch Panel. Use of a wrist strap is recommended. Do not use conductive tools to change parts or jumper settings in the Optical Isolation Patch Panel.

NEBS Compliance
This Class 2 data communications equipment has been Level 3 NEBS compliance tested and approved under the guidelines specified by the Bellcore GR-63-CORE, and Bellcore GR-1089-CORE Technical References. The CBM Optical Isolation Patch Panel conforms to the UL Standard for Safety, ANSI/UL 1950, Third Edition.

CBM of America maintains a 24 hour support organization for the installation and operation of this product. Call 800-881-8202 with the serial number of the product and a technical support representative will return your call promptly.

Product Description
The CBM Optical Isolation Patch Panel was designed to protect telecommunication network elements from ground loop induced equipment failures. The Optical Isolation Patch Panel converts data signals to light pulses and creates an optical gap to isolate any grounds. This allows the user to connect network elements from both the toll area and the switch through common equipment regardless of the individual power sources. The Optical Isolation Patch Panel can be equipped with any combination of isolated and non-isolated ports by adding or removing the isolation circuit cards.

Physical Specifications and Features

  • Twenty - four individually isolated circuits or port pairs at data rates up to 115 Kbps ( RS-232D ).
  • Isolation exceeds 750 volts between the ports of the port pair.
  • Ground to ground isolation exceeds 1000VDC.
  • Four groups of six RJ45 jacks on the panel. Each group is accessed from the back by a 50 pin Telco cable.
  • Standard WECO pin-outs from the 50 pin connector to the RJ45 jack.
  • Transmit and Receive activity from each port is displayed by dual color LEDs above each RJ45 jack.
  • Standard 19 inch relay rack mounting ( adapts to 23 inch with included brackets ), 3.5 inches high, 6 inches deep.
  • Power loss and individual port failure alarming to scan points.
  • Fully NEBS compliant.

Operational Specifications

  • Input power : 35 watts @ 48VDC nominal ( 110 AC available ).
  • 1 amp internal fuse. Fuse 3/4 amp at input.
  • Voltage range: 36VDC to 72 VDC.
  • Maximum output power: 5VDC at 4 amps
  • Operating temperature -10 to 40 degrees C.

Part Numbers

Part DescriptionPart Ordering Number
Optical Isolation Patch Panel *OPTOISO232-24
Optical Isolation Circuit CardOPTOISO232PCB
Pass Through Non-Isolation CardOPTOISONULLPCB

* Unless specified, the Optical Isolation Patch Panel ships with only the pass through non-isolated circuit cards installed. If the Optical Isolation Cards are ordered at the same time as the Patch Panel, they will be factory installed and tested prior to shipment.

Installation and Operation

Unpacking and Handling
Inspect the Optical Isolation Patch Panel carefully for any damage that may have occurred during shipment. If any damage is observed, contact CBM of America with the serial number and the packing list from the unit. Save the shipping container to return any damaged units. Always wear a ground strap when handling the optical isolation circuit cards.

Installation of the Optical Isolation Patch Panel
The Optical Isolation Patch Panel can be mounted in a standard 19 inch or 23 inch ( with provided mounting adapters ) relay rack. The Optical Isolator is preconfigured prior to shipment so it can be installed upon receipt. In the event isolation cards need to be added or removed, refer to page 2-5. To install:

  • Bolt Optical Isolator to Relay Rack
  • With power removed, connect Power and Alarm Cables to the Connector provided (see diagram below). The Connector then can be inserted into the keyed socket on the left rear of the Optical Isolation Patch Panel. Tighten the two retaining screws. Alarm leads can be wired to assigned scan points or an alarm circuit if available. The Isolator ships with the alarm leads set as 'normally closed'. An open condition will therefore bring in an alarm. This can be changed to a 'normally open' by moving the jumper on the Power Board. See the Power Board Diagram on 2-6.

Adding and Removing Circuit Cards

Isolation and Pass Through Circuit Cards
The Optical Isolation and Pass Through ( Null ) Circuit Cards can be added or removed with the power on ( see diagram below ). Be certain to wear a ground strap during any operation that involves the handling of circuit cards. To replace either circuit card, simply remove the access cover to the Optical Isolation Patch Panel and swap the cards. As you stand at the rear of the unit, the cards are inserted with component and connector side facing to the left ( the cards are keyed and can only fit the correct way ). The access cover is held in place by the two thumbscrews on the rear of the unit ( see page 2-2 ). When a Null card is replaced with an Isolation card, be sure to mark the change on the front of the Optical Isolation Patch Panel with the green triangular isolation indicators, provided with the unit.

Power Board Removal, Replacement, and Optioning
To remove, replace or option the Power Board, power must be disconnected from the Optical Isolation Patch Panel, and the access cover removed. Power is removed by loosening the two screws on the Power and Alarm Terminal Block on the rear of the unit ( see page 2-4 ). The access cover is held in place by the two thumbscrews on the rear of the unit ( see page 2-2 ). Be certain to wear a ground strap during any operation that involves the handling of circuit cards. The Power Board is held in place by two retaining screws on the outer left side ( when viewed from the rear of the unit ) of the Optical Isolation Patch Panel ( see page 2-3 ). Remove the retaining screws and disconnect the four power bus cables. The Power Board can now be removed. Once removed, you will be able to option the alarm conditioning to 'normally closed' or 'normally open' by moving the P1 Jumper ( see diagram below ). The Optical Isolation Patch Panel ships with the P1 Alarm Jumper in the 'normally closed' position. The socketized Internal 1 Amp Fuse is also on the Power Board.

If the Green Power / Fault LED is lit and the Transmit and Receive LEDS are also lit (on active circuits that are optically isolated) the Optical Isolation Patch Panel is working properly. Refer to the table below if any other condition is present.

Pin Assignments
All of the RS232 signals are referenced to Signal Ground on an individual port basis and isolated from any other signal or ground on any other port.


Optical Isolation Connectivity Guidelines Applies to Model 232-24


Installation of a new Optical Isolation Patch Panel:
When making new network element connections through the Optical Isolation Patch Panel, follow the IEEE signaling convention detailed on the diagram below.

Replacement of an existing non-isolated patch panel:
Special attention must be exercised when replacing a non-isolated patch panel with the CBM Optical Isolation Patch Panel. Existing connections between the retired patch panel and the associated network elements must be compliant with the signaling diagram above. Specifically, care must be taken to insure that NO signal is carried through on PIN 1. Many legacy cable assemblies manufactured by AT&T tied Signal Ground to Frame Ground carried through on PIN 1. This included cable and connector part number ED5P055-31 Groups 130, 131, 132, 138, 139, 140, 147, 148, 149, 150, and 151. This condition will negatively impact the signaling characteristics of the circuit, cause intermittent connectivity problems, and may fail completely.