What is a Siamese Cable?

Siamese cable is a versatile and widely used type of cable that combines video and power transmission in a single package. It is commonly employed in surveillance systems, particularly for closed-circuit television (CCTV) installations.

This guide aims to provide an in-depth understanding of Siamese cable, including its size, maximum distance, applications, and waterproof capabilities.

What is a Siamese Cable?

A Siamese cable, also known as a Siamese RG59 cable, consists of two main components: a coaxial cable for video transmission and a power cable for supplying electrical power. These two cables are bound together in a single jacket, allowing for easy installation and organization.

The coaxial cable typically carries the video signal from the security camera to the recording device or monitor, while the power cable provides the necessary electrical power to operate the camera.

What Size is a Siamese Cable?

Siamese cables are available in various sizes, with the most common being RG59. RG59 is a standard coaxial cable used for analog video transmission. It has a relatively thin diameter, typically around 0.24 inches (6.1 mm).

The power cable bundled with the RG59 coaxial cable is generally 18 AWG (American Wire Gauge), which is suitable for carrying the required power to the security cameras efficiently.

What is the Maximum Distance for Siamese Cable?

The maximum distance a Siamese cable can transmit a video signal without significant degradation depends on multiple factors, including the cable quality, video resolution, and type of equipment used.

In general, RG59 Siamese cable can effectively transmit video signals up to distances of around 500 to 700 feet (150 to 210 meters) without requiring any signal amplification or signal loss compensation. Beyond this distance, signal quality may deteriorate, leading to degraded image quality.

To extend the maximum distance of video transmission, signal boosters or video amplifiers can be employed. These devices help to strengthen the signal and maintain video quality over long cable runs.

Additionally, utilizing higher-quality Siamese cables, such as RG6 or RG11, can enhance the maximum distance capabilities, allowing for longer video transmission without signal degradation.

What Is RG59 Siamese Cable Used for?

RG59 Siamese cable is primarily used for CCTV and surveillance system installations. It is a popular choice due to its flexibility, ease of installation, and cost-effectiveness.

The coaxial component of the cable ensures high-quality video transmission, enabling clear and sharp images from the surveillance cameras.

In addition to video transmission, the bundled power cable simplifies the installation process by eliminating the need for separate power wiring. This feature is particularly advantageous for outdoor or large-scale surveillance systems, where multiple cameras are involved.

RG59 Siamese cable is commonly employed in applications such as residential security, commercial surveillance, retail stores, banks, and educational institutions.

Is Siamese Cable Waterproof?

The waterproof capabilities of Siamese cables depend on the specific model and manufacturer. While some Siamese cables are designed with a water-resistant jacket, providing protection against light moisture and weather conditions, they are not fully waterproof. Therefore, it is essential to consider the environment and conditions in which the cable will be installed.

For outdoor installations or areas prone to heavy moisture, it is recommended to use additional protective measures such as conduit or conduit seal fittings to safeguard the Siamese cable against water damage.

These protective measures ensure the longevity and reliability of the cable, preventing potential issues caused by water infiltration.


The riamese cable is a practical and efficient solution for transmitting video and power signals in surveillance systems. Its combination of coaxial and power cables simplifies installation, reducing time and costs. Understanding the size, maximum distance, applications, and waterproof capabilities of Siamese cable is crucial for designing and implementing a reliable surveillance system.