Hardware18.03.2014

DEHN Protection South Africa introduces combined lightning current and surge arrester for protecting coaxial systems, DEHNgate

By weich

DEHNgate (DGA) is a family of lightning current / surge arresters designed as a cable adapter for protecting coaxial systems such as CCTV, mobile radio stations and antenna systems from potential damage. Hybrid filter technology ensures the device functions over a wide frequency range while offering the greatest protection levels. The coaxial DGA arrester family comes in different designs to suit a wide range of applications, with the various types of connectors and arrester technologies providing optimal solutions.

The space-saving DGA FF TV can be mounted onto a DIN rail to protect video, camera and satellite systems with several outputs; and is available with direct (VCD) or indirect (VCID) shield connection to avoid ground loops. For single applications, such as broadband cable connections, the device can be simply snapped into a wall-mounted adapter. The DGA FF TV arrester is the first of its kind to have an integrated measuring output for antenna signals, allowing the system to be easily tested.

If a DC supply is required for the antenna system, such as for a remote radio head, electrical down tilt, tower top amplifier, and so on, a hybrid arrester such as DGA LG can be used. The DGA LG utilizes a hybrid quarter wave shorting stub and de-coupled gas tube to pass the required RF frequencies while allowing the DC to pass through the device. With this technology you benefit from essentially 3 devices in one, a band pass filter, and lightning protection for both the RF and DC signals. Because the gas tube is decoupled from the shorting stub, the majority of the lightning energy is diverted to ground by the stub itself, allowing the gas tube to only come into action during a direct strike. This ensures the device will remain useable and maintenance free for more than 10 years.

The use of quarter-wave surge arresters is advisable if high partial lightning currents could be coupled into antenna lines, or if very high transmission performances are required. If additional remote supply is needed for the antenna, a combination of a gas discharge tube and quarter-wave technology (DGA LG) should be used.

All DEHNgate arresters are designed for superior RF performance in the signal path, offering the lowest VSWR (R/L) and, most importantly today, maximum PIM values of 150dBc. The filter technology ensures that better than 99 percent of the energy from the strike will be safely sent to ground, ensuring safe and consistent operation of your system for many years to come.

Spark-gap-based surge arresters have an internal gas-filled surge arrester and can be defined as a low pass. This also allows direct current (d.c) transmission. Voltage spikes exceeding the sparkover value of the gas discharge tube are discharged. These surge arresters provide large-area contact surfaces for a defined contact of the inner conductor with the gas discharge tube. This minimises material burn-off during the discharge process and ensures a constant transmission performance.

The arresters are manufactured of top grade materials, finished in a robust tri-metal plating, and are designed to give outstanding performance and endurance.