CTC-Technology by CITEL

The next level in surge protection

"Central“ - The central position of the disconnection device

The innovative CTC-Technology uses several MOVs, but only one disconnection device. This solo disconnection is optimally positioned at the center junction of all the installed MOVs.

Compared to traditional SPDs designed with multiple MOVs and multiple disconnections, each MOV is no longer connected to a separate disconnection device, but all MOVs in the SPD are connected to the same disconnection.

This allows for a more compact SPD design measuring in at only 2.5 divisions (45 mm), the DPVN is about one centimeter slimmer than comparable SPDs of similar surge ratings.

"Thermal“ – The central disconnection system is a very efficient use of the principle of Joule heating which increases safety by allowing for quick disconnection from the power system.

The innovative disconnection device of the CTC-Technology is thermosensitive and is highly response to temperature changes at the junction of the varistor blocks and their individual conductor leads. Designed with three identical and very short connections to the central junction point of the disconnection system, the heat generated during the dissipation process (Joule-heating) in each metal-oxide varistor (MOV) is able to reach the disconnector more quickly.

In addition, the connection of all MOVs to a single cut-off point allows the Joule-heating of the MOVs to act simultaneously on the single thermal response point of the centralized disconnection device.

Even during an event of extreme stress or an end-of-life scenario, the outer temperature of the Surge Protective Device (SPD) always remains very low. This is because the heat is concentrated in the CTC itself and the SPD disconnects from the power system before even marginal temperature increases can occur.

"CONTROL“ – All-pole disconnection with a dual mechanism

The innovative CTC-Technology not only disconnects faster but also safer and more reliably.

  • Minimizing the risk of short-circuit:
    Before the MOV goes into thermal runaway, the CTC-Technology disconnects not only the failing MOV but the entire SPD from the power system. This ensures that the operator replaces the entire SPD and that no pre-stressed MOVs remain in the system at a reduced capacity and safety level.

  • More safety through double separation:
    In SPDs with the new patented CTC-Technology, the individual poles are isolated from each other by an insulating safety barrier as a part of the disconnection mechanism. Arcs cannot penetrate this safety barrier. This method is a great improvement over conventional spring-based distance separators.

  • Double separation = double safety.

Benefits of the CTC-Technology

The innovative and patented CTC-Technology (Central Thermal Control) is an entirely new disconnection technology. It is safer, faster, and more compact than previous disconnectors. CITEL's cutting-edge technology is unique in the market and as such has been awarded a number of technical patents.

It counters the weaknesses of previous disconnection devices by:

  • Its thermo-sensitive solo separation point, which is spatially centrally placed in the SPD
  • The additional insulating safety barrier integrated into the isolating device for more reliable separation of the poles in the event of separation.

This game-changing technology brings a number of benefits for you:

  • Space savings due to a more compact design
  • Short conductor lengths between MOV and cut-off device
  • Fast triggering of the cut-off by combining the cumulative heating of all MOVs onto one single heating point
  • Reinforced electrical insulation barrier for even safer pole separation
  • Removal of all stressed components after a single tripping event
  • No risk of varistor short circuits
  • Much lower temperature of the SPD housing during disconnection events ensuring more safety for the user as well as for electrical devices that are in close proximity
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Miramar, FL 33025 USA
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