Analysis of Fine Gauge Network Cables - NADDOD Blog

Analysis of Fine Gauge Network Cables

NADDOD Adam Connectivity Solutions Consultant May 16, 2023

With the explosion of digital information, data centres are becoming more and more crowded with active devices and cables of all kinds. As an indispensable member of data centre network deployment, network cables are densely packed between various network devices. In order to save data centre space costs and to maintain data centre equipment more easily, fine diameter network cables have been widely used in data centre network deployment. Nevertheless, there are still many people who have many doubts about fine diameter cables, this article will answer some common questions about fine diameter cables, and hopefully help you better understand fine diameter cables.

Can Fine Diameter Cables Be Used as Normal Patch Cables?

The answer is yes. Fine diameter cable is a kind of network cable, as the name implies, in the diameter of the thin than ordinary network cable, and ordinary network cable can be used for the connection between two electronic or optical devices to achieve a variety of signal transmission. The American Wire Gauge (AWG) is used to indicate the thickness of the wire, which is 24 AWG for normal wires and 28 AWG for fine wires.

It is a cost effective and convenient upgrade to regular network cable, being 40% thinner and more suitable for use in tight spaces, and is often used for high density cabling in data centres. In high-density data centre cabling scenarios, fine gauge cable can reduce congestion in the cabinet and improve airflow within the cabinet, which is beneficial to the cooling of equipment within the cabinet. Generally speaking, the higher the ambient temperature, the more likely it is that equipment will have problems, so if your environment is not unusually hot, there is no problem using fine gauge cabling.

Disadvantages to Fine Gauge Cables. What about Reliability and Safety?

There are two sides to everything, and it is impossible to use a fine gauge cable without any disadvantages or drawbacks. The more obvious disadvantages of fine gauge cables are the high DC resistance and insertion loss, which limits the distance that can be travelled.

The DC resistance of a wire is a measure of the wire’s ability to resist the flow of current. The DC resistance is influenced by the length and diameter of the wire, the longer the length of the wire the higher the DC resistance, and the smaller the diameter of the wire the higher the DC resistance. Therefore, the DC resistance of a fine-diameter cable is greater than that of a normal cable.

The new TIA 568.2-D standard recommends that when using 28 AWG wire in a link, the transmission distance should be kept within 15 m in order to maintain a DC resistance of 25 Ω or less.

DC resistance
Insertion loss is also an important performance parameter in measuring the quality of a cable and, like DC resistance, is affected by the diameter and length of the cable. As a rule, the smaller the diameter of the cable the higher the insertion loss and since insertion loss is directly related to the length of the link, the total length of the link must be taken into account when using fine diameter cables. For example, the derating factor (reducing the link length to less than 100m is called derating) for 28 AWG fine diameter cable is 1.95 and a 100m network link would need to be reduced to 96m - 90m of permanent link and 6m of cable.

Although the 28 AWG fine diameter cable is limited in distance, most users do not need to worry about this as fine diameter cable is primarily deployed in high density cabling areas of data centres and a 90m link distance is more than adequate for high density cabling areas of data centres.

In addition to the disadvantages mentioned above, security and reliability are key considerations when choosing a fine gauge cable. For example, Feisei (FS) thin diameter cable is made of pure copper conductors, which provides higher safety and overall performance compared to other copper-clad aluminium cables, and is UL listed and RoHS certified to meet high safety and reliability network connection requirements.

Are Fine Gauge Cables Suitable for Power over Ethernet (PoE)?

The answer is yes. While current industry recommendations for the wattage of power transmitted by fine gauge wire vary, it is certain that fine gauge wire can be used to implement Power over Ethernet (PoE). As of today, 28 AWG fine gauge cables can support PoE application type 2 (30W → PoE+, i.e. limited to 30W), with the possibility of supporting higher wattages in the future. This means that the fine diameter cable is currently only suitable for general low power PoE transmission for the time being. If your device is more powerful, it is still advisable to use a normal network cable.

When using fine gauge cables, the density of the cabling is higher due to the finer wires, which generates more heat. It is recommended that you do not bundle too many fine gauge cables into one bundle to avoid unnecessary damage due to overheating.

What Scenarios Are Fine Gauge Cables Suitable for?

Theoretically, fine diameter cables can be used in all applications where a cable is required, including PoE power. Due to their very fine gauge nature, they are often deployed in high density cabling environments, such as data centres and telecoms rooms. It should be noted that 28 AWG thin gauge cables cannot be used as horizontal or backbone cables, only as connections between devices, and they can only be used for a maximum distance of 10m.

Conclusion

Thinner cable equates to better airflow in the cabinet, less overcrowding and heat in the cabinet, space savings and greater manageability, making it an excellent choice for high density cabling with guaranteed transmission rates and reliability.