Category: Fiber Optic Cables

How to cross-over Fiber Cables?

Why cross-over Fiber Cables?
Occasionally, there will be instances in which you need to cross over fiber optics cables. The reasons may vary, but at the end of the day, the transmit (TX) and receive (RX) will need to be crossed in order to make a proper connection.
One of these situations is when you have to make a connection, and the cable manufacturers, instead of crossing the cable from end to end, they run them straight through. In other words, when you try to plug in you take the TX from one end but the other end shall also be a TX, which will definitely not work.
That being said, you need to take the TX and plug it into the RX of the other side of the port -this is what’s actually known as a cross-over. You need to make sure to identify the type of connector you are dealing with. If the fibers were reversed, all you need to do is to pull the fibers out, criss-cross them and put them back in, and then the link should be established.
One thing that should be definitely pointed out is that, whenever you are making a cross-over, you should be able to correct both ends properly. That is a good way to prevent subsequent confusions and misfortunes.
For example, you may have done a single cross-over connection within a panel that contains hundreds of them. So this may be not only inconvenient to you, but to the rest of the team in charge of managing those connections.
Another scenario you may have is to have an LC connectors on both sides. To cross over these fibers, all you need to do is to take the fiber connectors out of the holding bracket and criss-cross them manually. The way to do this is, to first pinpoint how the connectors are put together. If they’re split on the bottom, for example, the fibers should come out of the bottom, so you need to figure out a way to pull the fiber out and repeat the procedure for the other one.
Then make sure to handle carefully and not bend any fiber too much so you don’t break it, and then you reattach the bracket to the fiber and make sure it’s sealed properly just by taking a close look at the mechanism of the connector. Sometimes you will hear a click when you lock the bracket. Also, make sure both connectors are put together at the same height so that when you plug them in you can establish a proper connection.
Another scenario that you may come across, it’s the one in which you may have a different type of holding bracket on one of the ends. In this case, you need to pull the fiber out of the bracket. Just to be very careful to identify the orientation so you can keep it after you tear the bracket apart to make a proper cross-over. Once you have the right bracket, insert the fibers into it and make sure to make an appropriate link.
Be advised that every bracket has a particular mechanism, so look at it closely so you can make a good change. If you feel like you’re forcing the fibers too much, or that the mechanism is not loosing up organically, then you may be making a wrong move and you take the risk of breaking the fiber.
Long story short, the reason fiber cables need to be crossed is rather simple: when connecting fiber from one device to another, the fiber strands need to be cross so that TX goes to RX on each end. So if you face a situation like the ones explained above, you don’t need to worry. Fibers can -and must- be crossed-over. Just make sure you’re making the necessary adjustments in a delicate yet competent way to properly establish the connection you need to make.

Is it OK to bend a Regular Optical Fiber Cable?

One of the most common concerns amongst the installation of fiber cables is related to the possibility of bending a fiber cable or not. Worrying about this issue comes off rather naturally: if one does bend a fiber cable, let’s say around a corner, would that harm the cable? Or even more importantly, would it affect the quality of the transmission?
I’m sorry to share this news, but the answer is… yes. However, you do not need to let this concern grow out of proportion. You just need to take under consideration the following bits of information we’re about to show you, and you will be able to get over any issue you may have in regards to the bending -or not- of your fiber cables.
Under ideal conditions, there should be no loss of light within the fiber cable, which is one of the greatest features of fiber cables in the first place. Nonetheless, the scenario surrounding our actual installations are very far from that dreamy or utopian setting.
Depending on the way we install our systems, from the way we configure the connections through the actual alignment of cables, the inevitable losses of operating within the real world can be reduced or increased -and in this gap, it’s exactly where your control plays an essential role!
That control should be based on solid information. That being said, you should be aware of a parameter called “Bend Radius”, which is the minimum radius a cable can be bent without suffering any sort of damage. In other words, the smaller the bend radius, the larger the flexibility of the cable. Some manufacturers indicate the Bend Radius of fiber cables (Beyondtech surely does, is in its packaging and in their datasheets), but if you don’t have that information, you should know that the typical Bend Radius for fiber patch cables is around 30 mm.
Remember that you should be able to take any action that reduces those inevitable losses, that’s why it’s so important that you know this factor: bend loss starts happening only when the fiber cable is being bent at a higher measure than the cable’s maximum bend tolerance.
When installing your systems, you also need to be careful that the jackets have not only been perfectly built but that they’re also perfectly connected, since flaws in either one of these instances will result in losses in dB across time.
Another factor you need to take into consideration is pressure: if you tight your cables one against the other too tightly, that excess will generate leaks in the long term. Another eventuality you must avoid is when you have heavy objects pressed against the cables, just because that will definitely provoke an increase in losses. (This of course only applies to indoor cables)
As the supervisor of your network, you should develop the habit of constantly taking a thorough look at your installations: sometimes objects move after unforeseeable displacements, or get bigger thanks to high temperatures, so that object that originally didn’t disturb the rest of your installation may actually do it after a while.
Long story short: it is OK to bend your fiber cable, but you just need to be careful. You now know some facts that can lead you to properly design and implement strategies to reduce the losses that will inevitably come your way when using your fiber cables for installing your networks.

What is cable blowing? How it works?

With the rapid development of modern science and technology, optical communication technology in all aspects of life have been applied, which makes it received more and more attention. Optical cables, as the carrier of data transmission for optical communication, the proper laying of optical cable is a good guarantee for the dissemination of information data. For a long time, the most common way to lay the cable is to lay the cable directly into the underground, which has been widely promoted and applied.
Another way is embedding ducts. Put pipes through the ducts when necessary. Later, the cables should be inserted into the duct by pull, that is, drag them into ducts.
By the fear of force of friction may easy to cause break or deckle-edged of fiber cables, lubricant/oil is pre-applied on the ducts. However, the lubricant will accumulated on the bottom of due to gravity.
Later, scientists found a new way to laying cable by changing a thinking, laying air-blowing cables. Sometimes called “cable blowing ” , these methods use a high-volume air flow (7 bar back pressure) to “push” the cable. Most blowing machines also have mechanical “pushing”, where the cable is pushed by traction rollers as it enters the duct.
What is the advantages? The outside duct is of PVC, inner pipe is on silicone. Silicone pipe is soft, flexible, but it’s not liquid, won’t slide to be piled. Fibers will be blown in when necessary.
That is cable blowing. It’s more gentle to laying cables compared the ways applied before.
NKF company from Netherlands invented a new execution methods for cable blowing. They use a PVC duct with diameter of 40mm, which allows a number of cables blown in, so project can be staged construction according to business needs and capital situation. Currently, NKF company has successfully applied this new construction method to the cable trunk project from San Diego to Phoenix, the west coast of USA. The project is about 650km totally, the final design of the cable size is 288 cores(5pcs multiply 60 cores fiber cables), divided to 5 constructions. Initially, they only blew one 60 core cable and 5 pipes. In the following days, blow other cables to the rest deserved pipes according to demands. As the plan, the rest construction will be completed in the following 10 years in 4 different times. This will not only meet the current fiber needs, but also save the initial investment costs, warmly welcome by the operating company.
The key features of the cable blowing:
Protect the cables’ performance better: compared with other cable laying methods, the tension of cable during the laying process is relatively even and much smaller;
The laying process is simplified, it’s faster and more cost-effective to laying cables;
The length of one single laying is much longer: you can adopt longer fiber optic cable to reduce the number of joints and diminish the attenuation;
The number of manholes and hand holes on the pipeline lines can be greatly reduced;
Labors for laying execution is reduced.

the armored fiber optic patch 10G cables are small diameter

Armored fiber optic patch 10G cables uses stainless steel armor inside the jacket, which helps make it resistant of high tension and pressure. It retains all the features of normal patch cord, but much more stronger. When individuals use such armored 10G cables, they don’t need to worry the rodent animals such as the rats may bite the cables and make them broken. It may resist the load of an adult person, and it is difficult to break when bent or dragged. The interior armor can safeguard the entire cable from rodent. With stainless steel tube within the outer jacket to safeguard the central unit from the cable, the armored fiber optic patch cables are simple to use in harsh invironment. Although armored QSFP+ 10G cables are strong, they’re actually as flexible as standard fiber optic patch cords and could be bend randomly without having to be broken.
Installation procedure and maintenance is also easy. They’re ideal option for people who is seeking fiber optic patch cords with addtional durability and protection in addition to light weight. They retain the feature of all common types fiber optic patch cables, they are flexible to deploy in FTTH projects inside the buildings, normally the armored fiber optic patch 10G cables are small diameter and with PVC jacket, suit for indoor only use, outdoor usage fiber optic patch cables can also be found, they are with heavy PE jacket. They can be used directly in full duplex various harsh environment without additional protection.they can save space, reduce construction cost, making the constant maintenance more conveniently. Furthermore, the stainless steel tube prevents optic fiber from damage, which improves security and stability of the system.

which also use the SFP+ Cables cabling

This has caused the Fibre Channel community to create a Fibre Channel over Ethernet (FCoE) specification that helps to preserve the native protocol and its installed base. The InfiniBand community has similarly created its RoCE, or RDMA over Converged Ethernet, standard specification. RDMA is Remote Direct Memory Access, a low-latency and low-power technology used with InfiniBand architecture. So now these four interface, 10GBaseCR, 10GFCoE, 10GFC and 10GRoCE are implemented using the same SFP+ single-lane passive copper cabling.
10G SFP+ usage has grown dramatically because active copper and active optical SFP+ Cables have enabled increased market segments and longer-length applications like digital signage and AV systemsBesides Fibre Channel, other storage interfaces like NAS, iSCSI, iSATA and ATAoE are tunneled over Ethernet 10GBaseCR. These other storage interfaces are also tunneled over Ethernet 10GBaseT using Category 6a and Category 7a cabling.
There are open and closed Consortia de facto standards using these multi-protocols on so-called collapsed architectural fabrics like the Unified Computing System, which also use the SFP+ Cables cabling.Besides UCS, there are several other de facto standard unified style networks, which also use the SFP+ but with different encryption in memory mapping of the embedded plug EPROMs.
One wonders if all of these IO interfaces will expand and use the newly developing 25/26/28Gbit/sec QSFP++ module and cabling system, which is being standardized through the SFF-8661/2/3 specification.

How to Terminate Fiber Optic Cables?

Since the late 1970s, various connectors and termination methods have been brought to market. Now in the common case, cables are terminated in two ways: use connectors to make two fibers jointed or to connect the fiber to other network gears; use splices to make a permanent joint between two fibers. And for the former method, you may have little confusions to deal with it. So today this paper will teach you how to terminate by taking an example of fiber optic cable using epoxy.
First and foremost, use a proper fiber stripper to carefully slide the jacket off of the fiber to a bare fiber. When you are doing this, be careful that try to avoid breaking the fragile glass fiber. After that, mix the epoxy resin and hardener together and load it into a syringe (If you use the pre-loaded epoxy syringes that are premixed and kept frozen until use, then you don’t do that). And next you must inject the epoxy from the syringe directly into the connector ferrule.
Once you have well prepared the epoxy for your connector, you can insert the fiber cable gently into the terminus inside the connector wall and make the bare fiber core stick out about a half an inch from the front of the ferrule. In the case that your cable is jacketed, you may need a crimping tool, such as Sunkit Modular Crimping Tool, to secure the connector to the jacket and strength the cables. Usually two crimp tools would be perfect to this operation.
Next, you can just wait the epoxy to cure. During this process, in order to make sure the end of the fiber is not damaged while curing, you should place the connected end in a curing holder. And when this is done, just place the cable and curing holder into a curing oven. But you may worry about “wicking” while curing with a conventional oven. All you have to do to avoid that is to make the end face down, which can ensure the epoxy does not come out of the back side of the connector and compromise the strength member of the cable. Remember: your epoxy curing must in accurate times and temperatures.
After the epoxy cured sufficiently, fiber cleaver tools will be in use to cleave the excess protruding fiber core so that it could make the fiber close as much as possible to the ferrule tip in case of fiber twisting. Once cleaved, you have to dispose of the fiber clipping. There is a point you should think highly of that you must use a regular piece of tape to retain your fiber debris, or they will easily end up in your skin or even in your eyes or respiratory system.
When you finished the fiber cleaved work, you could need fiber polishing tool to remove the excess epoxy from the ferrule tip and buff out any imperfections on the surface of the fiber. A smooth fiber surface can help to reduce the loss of the light. Last, if you have done all the above work, you may move on to the cleaning of the ferrule and fiber tip. After that, the whole termination procedure is done.