Starting at $269.00
  • Usually ships in 1-2 weeks



  • Range of voltage ratings available to cover all process related signals
  • Maximum surge current 10kA (8/20μs waveform)
  • Single and dual pair versions
  • Fully auto resetting, maintenance free
  • Plastic ABS enclosure rated to IP65 (NEMA 12 and 13)
  • Ready fitted with cable glands
  • Easy installation with mounting via M5 external earth stud
  • Multi-stage hybrid protection circuitry — high surge absorption capability
  • 10 year product warranty


The MTL mSA series of surge protection devices are designed to safeguard remote electronic equipment from surges on signal and data cabling. Models are available in a range of working voltages to cover all process-related signals such as RTDs, THCs, 4/20mA loops, telemetry outstations, shut-down systems and fire and gas detection. Isolated applications are particularly at risk as they are regularly exposed to lightning activity and therefore suffer frequent damage. The mSA series surge protectors increase system reliability, prevent costly damage to equipment and reduce maintenance costs at remote sites.

Modules are available over a comprehensive range of voltage ratings: 6V, 16V, 30V, 51V and 75V , covering all process related signals such as RTDs, THCs and 4-20mA loops. Single and dual pair versions allow installation flexibility and are ideal for 3 and 4-wire RTD applications. The mSA design incorporates test points to enable fast maintenance checks. Removable links enable the ‘high' and ‘low' energy sections to be tested independently.

The mSA series is also suitable for Telecom applications — private wire installations can be protected using the standard mSA range. Public Switched Telephone Networks (PSTNs) are served by the specifically designed mSAPN Series which utilizes the same rugged enclosure as the mSA range. mSAPN devices are available with either single or dual linepair protection networks, like the mSA units, and are supplied with IDC-type terminals. An IDC insertion tool is supplied for ease of convenience.

The weatherproof enclosure of the mSA series is rated at IP65 making it particularly suitable for remote locations which are regularly exposed extreme weather. These self-resetting devices continue to protect even after a surge has passed making them maintenance free, again ideal for remote locations. The maximum surge handling capability of the mSA range units is 10kA. Sophisticated hybrid circuitry protects vulnerable equipment without affecting normal operation, passing ac or dc signals with little attenuation while diverting surge currents safely to earth and clamping output voltages to safe levels.