Debunking the Myths

The debate between coaxial and fiber optic cables in the sewer inspection industry has gone on for years. Many still consider fiber to be fragile and unreliable, but in reality, modern fiber optic cable has proven it’s here to stay. Despite its obvious benefits, fiber is often misunderstood. Let’s clear up the misconceptions and highlight why modern fiber optic cables are the preferred choice for modern sewer inspection systems.​

 

Fiber Optic’s Past Fragile Reputation

 

Early fiber optic cables, especially those without a thicker outer jacket, were susceptible to damage. These early versions were prone to breakage, and at the time, there was a lack of education and field experience to handle them properly. This created a lingering perception that fiber is fragile and unreliable. Unfortunately, this misinformation about fiber’s reliability has carried over, preventing many from taking advantage of its benefits.

 

Armored Fiber Optic Cables: Built for Harsh Environments

 

Today’s fiber optic cables are engineered with armored layers, making them crush-resistant and abrasion-resistant. These modern cables are designed to withstand the harshest environments and handle real-world abuse, such as manhole lids slamming down on cables or trucks running over them.

This durability is far beyond the expectations many people still have of fiber. Unlike fiber, coaxial cables are susceptible to bends due to the way it is constructed. In a coaxial cable, the conductor (typically copper) must be placed in the center of the cable to avoid noise, etc. The center of the cable is also the most prone to bends/breaks, so this is where fiber really has an advantage.

Fiber optic cable uses thin strands (fibers) of silica for its conductor, and can be placed anywhere within the cable bundle. Think about bending a metal paperclip back and forth, over and over – it’s eventually going to break. You don’t have that problem with fiber.

One customer, a contractor who inspects with their PANORAMO® 4K System daily, covered over 500 miles before needing their first re-termination.

 

Fiber Optic Cable for Sewer Inspection

​Superior Image Quality and Reliability

 

One of the biggest advantages of fiber optic cable is the uncompressed HD signal it delivers. While coaxial cables can degrade over long distances or after physical damage, fiber offers a lossless signal, even with partial damage to the cable.

HD inspections should deliver crisp, clear images, with no latency. Fiber doesn’t suffer from common issues like crawling lines, grainy video, or flickering, which are often experienced with coaxial cables. This is especially important as the industry moves toward HD and 4K imaging as its new standard.

 

We put our HD inspection camera (ORION® 3) head-to-head with one of our SD CCTV cameras (ORION® SD) in the same section of pipe. See the details first hand in this side-by-side comparison video.

HD-Over-Coax

 

If your HD inspection system uses a coaxial cable, it is likely using a method called HD-Over-Coax. In this process, your HD signal from the inspection camera is converted to an analog signal. The analog signal is then sent down the coaxial cable to your computer where that is converted back to an HD signal. In the end, you get a better picture than standard definition, but there are some issues that often occur with analog conversion:

• High Latency (Video Lag): Even a 1-2 second delay can frustrate operators and increase the risk of damaging the system.

• Degraded Signal At Long Lengths: Coaxial cables will degrade over longer distances due to resistance in the components of the cable.

• Low Light Causes Distortion: If you find yourself in a dark environment, graininess and visual noise become more pronounced.

• Incorrect Rendered Colors: Accurate color is crucial for identifying defects in different pipe materials

• Over-Saturated Images: Overexposure reduces image clarity, especially in light-colored pipes (PVC). Appears pixelated or blown out.

• Depth Rendering Muted: Analog compression often removes finer image details, including depth cues.

Manufacturers like IBAK, recognized the use-case for fiber optic early on, and completely re-designed their inspection systems from the ground up to provide true HD (1080p) and 4K imagery.

 

Repair From the Field: Simplifying Maintenance

 

Contrary to common myths, fiber optic cables can be repaired in the field efficiently. Any technician with previous cable re-termination experience can perform a fiber repair. The process is nearly identical, with only a few added steps. With the added protection fiber provides, you’re not going to experience nearly as many breaks compared to coaxial cable. Operators who take proper care of their cable should typically expect up to 5x fewer breaks out of their fiber compared to coaxial cable. Protecting your cable with downhole rollers and manhole rollers will extend its life even longer.

If you are interested in learning how to re-terminate an IBAK fiber optic cable, be sure to watch this step-by-step guide:
Fiber Optic Cable Re-termination

 

Other Benefits of Fiber

 

There are many obvious benefits fiber provides for sewer inspections. Better images, lossless signal, and an overall more rugged cable design. Fiber has some less obvious traits that give sewer operators an advantage when conducting video pipe inspections:

• Lightweight: Coaxial cables are heavy by nature. As you may know, pulling a heavy cable is half of the battle during an inspection. That’s why IBAK builds their camera tractors out of dense materials to increase traction in the pipe. Fiber optic cable is much lighter, reducing the strain on your system and increasing the distance you can pull the cable.

• Thick Outer Jacket: With fiber optic weighing much less than coaxial cable, it can afford more protection in its outer layer without affecting performance. In the sewer, you can come across sharp debris and jagged boulders. The added protection will reduce breaks and costly repairs.

• Easy to Locate Faults: If your fiber does break, it is much easier to locate where your cable has failed. There are many 3rd party instruments available that allow us to plug our fiber into one end and shoot a laser through it. In a dark room, you can easily verify where the fiber broke, identified by a glowing red point on the cable. A test meter works great for this as well to identify the length of cable affected.

 

​Implications for Contractors and Municipalities

 

For contractors and municipalities, adopting fiber optic cables in sewer inspections translates to enhanced reliability, reduced maintenance, and superior imaging. Embracing this technology ensures more efficient operations and long-term cost savings.​

Fiber optic cable represents the future of sewer inspections. It’s reliable, repairable, and durable – there’s no longer a trade-off between performance and cost. Contractors and municipalities adopting fiber systems for sewer inspections ensures future-ready operations and long-term cost savings.

If you’re evaluating inspection systems, it’s important to question anyone recommending coax and consider the tangible benefits of modern fiber optic technology.​

 

Ready for the Future

 

Armored fiber optic cables have redefined sewer inspection standards, offering unmatched durability, image clarity, and ease of maintenance. Dispelling outdated myths and embracing these advancements is essential for industry progress.​

 

 

FAQs

Q1: Are modern fiber optic cables durable enough for sewer inspections?
A1: Yes, modern armored fiber optic cables are engineered to handle the harsh environments of sewer inspections. They are crush-resistant, abrasion-resistant, and built to endure impacts and heavy use.

Q2: Can fiber optic cables be repaired in the field?
A2: Absolutely. With basic tools, technicians can perform re-terminations on-site, restoring cable functionality quickly and efficiently.​

Q3: How does the image quality of fiber optics compare to coaxial cables?
A3: Fiber optic cables deliver uncompressed HD signals with no loss of quality over distance or partial damage, unlike coaxial cables, which often suffer from video issues such as flickering, graininess, or crawling lines.