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The ESP RTD, RTDQ & SL RTD Series is a combined Category D, C, B tested protector (to BS EN 61643) suitable for 3-wire RTD systems to protect monitoring equipment. For use at boundaries up to LPZ 0 (ESP RTD & ESP RTDQ) or LPZ 0 (ESP SL RTD) to protect against flashover (typically the service entrance location) through to LPZ 3.

Available as standard ESP RTD format, or compact ESP RTDQ and Slim Line ESP SL RTD versions for installations where a high number of lines require protection.

Features & benefits

  • Protects all three wires on a 3-wire RTD system with a single protector
  • Very low let-through voltage (enhanced protection to IEC/BS EN 62305) between all lines
  • Full Mode design capable of handling partial lightning currents as well as allowing continual operation of protected equipment
  • Repeated protection in lightning intense environments
  • Low in-line resistance minimizes reductions in signal strength
  • Built-in DIN rail foot for simple mounting to top hat DIN rails
  • Convenient earthing through DIN foot and/or earth terminal
  • ESP RTD can be flat mounted on base or side
  • ESP RTD and ESP RTDQ have colour coded terminals for quick and easy installation check
  • ESP SL RTD has ultra slim 7 mm width ideal for compact protection of large numbers of lines (e.g. process control installations)
  • ESP SL RTD includes two stage removable protection module with simple quick release mechanism allowing partial removal for easy line commissioning and maintenance as well as full removal for protection replacement
  • ESP RTDQ available with Push Terminals (ESP RTDQ/PT) for simple 'spring' connections, to provide fast and reliable cable termination
  • ESP RTDQ and ESP RTDQ/PT have UL497b approval under file E240341