Simple Guide to Choose Fibre Patch Leads
1. Single-mode or multimode fibre?
A. It depends on Fiber optic equipment/device
If the equipment/device is single-mode, then fibre patch leads must be single mode.
If the equipment/device is multimode, then fibre patch leads must be multimode.
B. It depends on transmission distance
If the transmission distance is long, like 10km or more, then single mode the right choice.
If the transmission distance is short, multimode is a good choice. Normally, the transmission distance can not exceed 2km if multimode fibre is used.
The table below is showing the transmission distance for different multimode fibre.
|OM1 62.5/125||OM2 50/125||OM3 50/125||OM4 50/125|
|40&100Gb/s||Not required||Not required||100m||150m|
How to distinguish single-mode and multimode fibre cable?
Yellow jacket is single-mode.
Orange jacket is multimode OM1 & OM2. Light blue is OM3 & OM4
The most accurate way is to see the text printed on the cable jacket.
It is single-mode when it mentions “SM”, “Single Mode”, “9/125”, “10/125”, “G652D”, “G657A”
It is multimode when it mentions one or more of them: “MM”, “Multimode”, “OM1”, ”OM2”, “OM3”, “OM4”, “OM5”, “62.5/125″, “50/125”.
Standard fibre optic connectors are SC, LC, FC, ST which are widely used to make fibre patch leads.
FC, ST is used on equipment/device, also sometimes are used on ODF and termination box.
SC is widely used on ONU, patch panel; LC is the most popular ones, it is small and save much space, is widely used in high-density applications like data centre.
3. PC or APC
There are two polish types, PC and APC. If high return loss is required, then APC is a better choice.
One more thing is important, PC can not mate with APC. PC only mate with PC, APC only mate with APC.
4. Insert loss & Return loss
According to IEC standard, there are four grades of attenuation caused by the connector. Please see the table below. High level always means high cost. Normally anfkom’s fibre patch leads are made with insert loss <0.3db, which is between Grade B and C. we also can provide fibre patch leads with insert loss<0.2db or even insert loss<0.1db, which is much better than grade B.
5. Outer Jacket
There are 3 types of Jacket material that widely used to make fibre patch leads in the market.
PE Polyethylene)PE has excellent properties of moisture and weather resistance, and has the good electrical properties over a wide temperature range. It’s also abrasion-resistant. So PE is the standard jacket material for outdoor applications.
PVC (Polyvinyl Chloride )PVC is usually low-cost, flexible, fairly rugged, and a flame/oil-resistant material, so it can be formulated to function in a variety of environments and applications. In other words, it can be used as the jacket materials for both indoor and outdoor cables
LSZH (Low Smoke Zero Halogen)LSZH jacket is free of halogenated materials which can be transformed into toxic and corrosive matter during combustion. LSZH is environmental friendly materials, and it is more expensive than PVC.
PVC and LSZH are popular for indoor applications.
But if high fire-resistance required, ONFP or ONFR material is a choice.
ONFP and ONFR are defined on the UL standard. ONFP fibre patch leads are installed in the plenum area.
6. Cores Number
Normally the fibre patch leads are simplex or duplex, also multicore patch leads will be used in some applications. The multicore cable diameter is big, It is strong and not so flexible. Sometimes, people bundle 48 duplex fibre patch leads instead of using 96F multicore fibre patch leads.