How to manage polarity in MTP® / MPO backbone and duplex optical fibre links
News - January 19, 2017
New Product – LC-LC push & pull tab duplex patch cords
Managing polarity in duplex optical fibre links is essential in ensuring correct transmission performance. Transmit ports on end 1, must communicate with receive ports on end 2 and vice-versa. Generally, this is very straightforward, however when utilizing certain MTP/MPO backbone cabling configurations, the transmit and receive fibre pairs may become reversed.
In many modern data centre environments, MTP®/MPO cabling solutions are becoming more widely accepted due to the many advantages that it offers, including its ability to provide a high density connectivity platform. MTP/MPO links are designed and installed based on pre-defined connectivity methods, each with its own advantages.
ANSI/TIA-568-C.0 defines the various connectivity/cabling methods that can be potentially adopted – Method A, B or C.
| Connectivity method | Array connector cable type | Array Adaptor type | Duplex patch cord type |
| A | A | A | One A-to-B and one A-A per duplex channel |
| B | B | B | A-B |
| C | C | A | A-B |
A common connectivity method for duplex signals is method A, which utilizes Polarity A cassette’s and trunks within a standard cross-connect configuration. In this configuration, one end of the duplex link must have an A-B LC duplex patch cord and the opposite end must have an A-A duplex patch cord, which ensures that transmit and receive ports are correctly aligned. Therefore, 2 different types of patch cords are required and must be known in advance.
Utilising simplex LC patch cords is another option, however in high density networks, this just increases congestion, due to the additional cable diameter.
The Warren & Brown LC Duplex reversible polarity, pull tab patch cords provide an effective means of managing and correcting polarity in the field. This flexible product provides the perfect solution for ensuring the correct alignment of transmit and receive ports in duplex optical fibre links. By simply removing the outer cover, the LC fibre clips can be easily rotated without any tools, which can transition an A-B patchcord to an A-A patch cord in a matter of seconds.
Density has and always will be important in the ICT Industry. The Warren & Brown LC patch cords have been designed with this in mind and sport push/pull tabs that are ideal for high density environments, allowing easy access to the connection point.
Features and options:Furthermore, being specially designed for high density applications in data center environment, LC Duplex Uniboot patch cords are part of Warren and Brown’s MTP®/MPO solution and feature a slim cable construction, with an OD of only 2mm, reducing congestion in cable management areas and pathways. A pull tab feature is also incorporated into this product, which allows for easy connection/disconnection in high density patching fields.
- Available with Multimode OM4 fibre or Singlemode G657A2 fibre
- Available in any length
- High quality connector performance
- Pull tab for easy connection/disconnection
- Reverse polarity in seconds
- LC Duplex connectors
- Small OD -2mm round duplex cable
These LC Duplex, reversible polarity, pull tab patch cords are only one part of the innovative WBT MTP®/MPO solution, which includes patch panels, cassette’s and various cable assemblies.
To view our full range of MTP Solutions ( MPO Solutions ), please visit the product page .