Data Center

5 Common Telcordia GR Questions Answered

Matt Baum

Singlemode fiber optic connector technology is relatively mature, but there are changes being made to optical performance that may impact how singlemode fiber optic connectors are measured and tested.

Telcordia Generic Requirements (GRs) provide Telcordia’s take on proposed criteria for telecommunications equipment, systems and services – essentially vendor-neutral technical specifications, including requirements, features, characteristics and performance testing for connectors and jumper assemblies.

 

The documents take into consideration a wide variety of factors: interoperability, network integrity, the needs of industry members, etc. Now part of Ericsson, Telcordia represents companies participating in the development of these GR documents.

 

To help you learn more about Telcordia GRs, we’re answering five of the most common questions we hear.

 

1. What do the Telcordia GR documents apply to?

Telcordia GR-326 is specifically for singlemode field-terminated connectors and jumper assemblies – not for multimode connectors or cable.

 

With a focus on outside plant environments, Telcordia GRs measure product reliability and quality to protect optical fiber in all types of operating conditions.

 

2. What is the purpose of the Telcordia GRs?

Telecommunications carriers can use GR documents to select products that meet deployment and performance needs. The GRs cover five sections:

 

  1. General Requirements, which discuss documentation, packaging, shipping, design features, product marking, safety and intermateability.
  2. Performance Requirements, which cover potential connector tests, as well as the performance criteria applied during testing.
  3. Service Life Tests, which mimic the stresses faced by connector assemblies in telecommunications plants.
  4. Extended Service Life Tests, which verify long-term connector reliability.
  5. Reliability Assurance Program, which ensures satisfactory, long-term operation of fiber optic connectors in a telecommunications plant.

3. How do Telcordia GR documents differ from other standards?

Just like ANSI/TIA-568 offers specifics on premise fiber cable and components, Telcordia GR-326 isdesigned specifically for telecommunications. This industry typically uses connectors in harsh environments that have wide temperature fluctuations, high levels of humidity and other types of contaminants exposure.

 

To make sure singlemode field-terminated connectors and jumper assemblies can perform well without being impacted by these factors, Telcordia GR documents call for longer, more intense tests.

 

4. What are the Telcordia GR tests like?

There are two tests that singlemode field-terminated connectors and jumper assemblies go through as part of GR testing.

 

Section 4.4.2 is a series of environmental tests conducted for a full seven days (168 hours). Loss and reflectance measurements are taken before and after each test. The difference is then documented. The tests include:

  • Thermal Age Test: Conditions include exposure to uncontrolled humidity and a temperature of 85 degrees C.
  • Thermal Cycle Test: Conditions include exposure to uncontrolled humidity and temperature cycles varying from -40 to 75 degrees C.
  • Humidity Aging Test: Conditions include exposure to 95% humidity and a temperature of 75 degrees C.
  • Humidity/Condensation Cycling Test: Conditions include exposure to 90% to 100% relative humidity at points indicated, with cycling temperatures ranging from -10 to 65 degrees C.
  • Post-Condensation Thermal Test: Once the singlemode fiber optic connector or jumper assembly dries out for 24 hours, the Thermal Cycle Test is run once again with the same conditions.
  • Dust Test: Conditions include exposure to severe dust.

Section 4.4.4 is a series of material and environmental tests that subject products to various potential contaminants:

  • Dust Test: Same conditions as mentioned above.
  • Adhesive Test: Conditions include exposure to a two-pound load to test the adhesive bond between the fiber and ferrule.
  • Airborne Contaminants Test: Conditions include exposure to a gas mixture.
  • Salt Spray Test: Conditions include exposure to distilled water with 5% salt content at 35 degrees C.
  • Immersion/Corrosion Test: Products are completely immersed in 250 mL of deionized or distilled water at 85 degrees C for two weeks.

Mechanical tests are also completed as part of the Telcordia GR documents (in Section 4.4.3).

 

5. Why are Telcordia GRs important?

If you want to be sure that singlemode fiber optic connectors and jumper assemblies will function well outdoors in telecommunications plant environments, choosing products with a Telcordia GR rating can help provide peace of mind.

 

As new singlemode fiber optic connector technology is unveiled, Telcordia GR documents will continue to be updated. GR documents for multimode connectors, small-form or miniature connectors, and LAN connectors may be coming from Telcordia in the future.

 

Belden has achieved Telcordia GR ratings – or is in the process of achieving them – for several products, including its new FX Fusion Splice-On Connectors. Belden will keep you updated as more products receive this rating, and as Telcordia updates its GR documents. Sign up for our blog notifications so you don’t miss a thing!