Fibre Cable – let me explain what OM2 means

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Fibre Cable – let me explain what OM2 means

With current light source technology, OM1 fibre cable has reached its performance limit in testing and in the field.

OM1 Fibre Optic Cable has been shown to severely limit a fibre optic link.


The introduction of 50-micron fibre offers as much as 10 times the bandwidth of 62.5 microns OM1 core Fibre Optic Cable.


OM2 Optical cables are quite similar to OM1 Optical cables and follow many of the same standards set out by the Telecommunications Industry Association.


OM2 Optical cable generally also comes with an orange nylon jacket much the same as OM1optical cable, however, the OM2 core size is 50 microns while the OM1 core size is 62.5 microns.


OM2 Fibre Optic cables most commonly use LED light sources.


This produces the same issues as OM1 Optical cable in where the bandwidth of the fibre optic link is severely impacted due to the LED’s inability to rapidly switch on and off.


For this reason, OM2 cable is still used in short-haul applications such as short-haul networks, Local Area Networks, and Private Networks supporting 10 Gigabit Ethernet at lengths up to 82 meters.


OM2 Optical Cable is more commonly used for 1 Gigabit Ethernet applications, however at lengths of up to 550 meters.


Then why is OM2 not routinely deployed?

Since the introduction of TIA standards, OM2 Optical cable has never seen significant growth compared to other cable types.


This can be attributed to factors such as;


–  the cost-benefit of OM2 which provides only slight distance and speed benefits compared to OM1,

– and the lack of future-proofing provided by OM2 due to its data rate and bandwidth limitations.


These limitations generally push fibre optic installers towards other cable types such as OM3 and OM4 Fibre Optic Cable.


These Fibre Optic Cables can be brought for slightly more than OM2 and provides many significant benefits.

However, switching to the required VCSEL sources and equipment needed for OM3 Fibre Optic Cable can be expensive.


Hence, there is a niche market for the LED-powered OM2 Optical Cable.

Image result for fibre optic led vs vcsel


For many years 62.5/125 µm (OM1) and conventional 50/125 µm multi-mode fibre (OM2) were widely the Fibre Optic Cable of choice.


The OM1 and OM2 Optical Cable easily supported required applications ranging from Ethernet (10 Mbit/s) to gigabit Ethernet (1 Gbit/s).


Their large core size made them ideal for use with LED transmitters.

These days Fibre Optic cables can be made to support 10 GbE up to 400 meters.

Laser optimized multi-mode fibre is designed for use with 850 nm VCSELs, eliminating the LED light sources requirement totally.