You must have experienced or heard of water damage to electrical appliances. An optical fiber connector is a device closely related to our network life.
Once it is damaged by water, it will cause power supply obstacles, deterioration of signal quality, deterioration of high-frequency signals, etc.
This blog will detail this impact and why we need fiber optic waterproof connectors.
1 . Two manifestations of water entering into optical fiber connectors
①Have you ever encountered a situation where the high-frequency signals become poor, or even snowflakes appear?
This may be due to water entering the connector and causing water to enter the cable.
Changes in the dielectric coefficient of the insulating layer cause the cable attenuation to increase.
This situation has a particularly large effect on high-frequency signals.
②Have you encountered power supply obstacles and signal quality deterioration?
This may be due to water entering the joint causing the joint to oxidize.
This causes problems with the lines fed by the common cable,
affecting the normal operation of the entire downstream amplifier.
At the same time, the signal quality deteriorates along with the increase in the slope.
2 . Why does oxidation occur?
In existing cables, the inner conductor is generally copper,
and the outer conductor is aluminum-magnesium alloy wires or aluminum shells.
Both the inner and outer conductors oxidize in air, especially in environments with water.
Copper can be oxidized at room temperature and high temperature.
Oxidation produces black copper oxide and basic copper carbonate, commonly known as patina.
But basic copper carbonate can be decomposed into copper oxide at high temperatures. These two oxidation products are both electrical insulators and insoluble in water.
So they greatly impact the feed and signal transmission of the cable TV transmission system.
3 . The effect of the oxidation phenomenon on optical fiber.
The verdigris formed at room temperature forms an insulating layer of oxide film between the inner conductor and the connector.
You can think of this as an equivalent capacitor.
High-frequency currents flow more easily than lower-frequency currents.
This is manifested as attenuation of both high- and low-end signals,
but the low-end attenuation is more serious.
In your opinion, this is a low-end low level, and there may be various interference patterns. Due to the existence of the oxide layer,
the conductivity of the inner conductor is greatly reduced,
the voltage drop of the cable in this section becomes larger,
and the voltage at the rear stage is insufficient.
The lower stage amplifier may work abnormally or even not work.
4 . What happens when the cable joint gets water?
If the cable joint is damp or water enters when the 60 V power supply common cable is transmitted.
- It is easy to discharge between the inner conductor and the outer conductor, generating a large amount of heat energy.
- The inner conductor undergoes a violent oxidation reaction to form black copper oxide.
- The density of copper oxide is greater than that of verdigris,and the attenuation of low-frequency signals is greater.
- The conductivity of the inner conductor is weaker and has a greater impact on the line.
And due to the existence of this oxide layer outside the inner conductor.
The electrical constant and the radius of the inner conductor change, and the cable impedance may be seriously mismatched.
There is a possibility of right ghosting in the post-stage circuit.
The outer conductor is usually made of aluminum-magnesium alloy wire.
Aluminum and magnesium are chemically active metals.
Once the water enters the joint, the inner and outer conductors will discharge and generate a lot of heat.
It will accelerate the corrosion of the outer conductor.
Once the outer conductor is seriously corroded, it will cause：
- The signal attenuation will become larger, and the outer conductor will be damaged.
- The conductivity of the conductor is greatly reduced,
- The power supply voltage of the rear stage may be low, and the amplifier does not work properly or does not work.
5 . How to solve the connector’s network failure caused by water?
The general practice to reduce network failures due to water ingress to the connector is to use waterproof connectors.
Due to the complicated construction process of waterproof joints,
the products of various manufacturers are uneven, and the level of construction personnel is uneven.
Moreover, the use of waterproof joints brings inconvenience to future maintenance.
Therefore, waterproof connectors are not used in some places, but ordinary radio frequency heads are used.
Due to the poor waterproof performance of ordinary radio heads,
even if the waterproof tape is used,
it is still inevitable that water will enter the joint.
It is a potential major hidden danger for the cable television system fed by the common cable. In some places, a simple method is adopted: adding a rain cover.
Although this method is relatively primitive, it is effective. To a certain extent,
the problem of water entering the joint is solved,
But at the same time, it brings about heat dissipation problems.
Because the rain cover is not in close contact with the amplifier,
The convection of the air on the outer surface of the heat sink of the amplifier is reduced,
the working temperature of the amplifier will increase, and various performance indicators will inevitably decline.
Therefore, choosing a high-quality optical fiber waterproof connector is the key to solving this problem.
As an experienced supplier of waterproof connectors in China,
Fibconet is willing to contribute to your FTTx problem,
Please do not hesitate to contact us for more information!