SD20/30R  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage: 385 VAC
  • Discharge Current: 20kA / 30kA
  • Max. Discharge Current:
    40kA / 60kA
  • Modes of Protection:
    1+1 (L-N, N-PE)

SD20/30R  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage: 385 VAC
  • Discharge Current: 20kA / 30kA
  • Max. Discharge Current:
    40kA / 60kA
  • Modes of Protection: 2+0 (L/N-PE)

SD20/30R  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage: 385 VAC
  • Discharge Current: 20kA / 30kA
  • Max. Discharge Current:
    40kA / 60kA
  • Modes of Protection: 4+0 (L/N-PE)

SD20S  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage:
    385 VAC (2+0)
    L-N: 385 VAC, N-PE: 255 VAC (1+1)
  • Discharge Current: 20kA / 40kA
  • Modes of Protection:
    2+0 (L/N-PE)
    1+1 (L-N, N-PE)

SD20/30R  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage:
    L-N: AC 385V / N-PE: AC 255V
  • Discharge Current: 20kA / 30kA
  • Max. Discharge Current:
    40kA / 60kA
  • Modes of Protection:
    3+1 (L-N, N-PE)

SD20S  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage:
    385 VAC (4+0)
    L-N: 385 VAC, N-PE: 255 VAC (3+1)
  • Discharge Current: 20kA / 40kA
  • Modes of Protection:
    4+0 (L/N-PE)
    3+1 (L-N, N-PE)
Überspannungsschutzgerät Typ 2 60kA 3+1Überspannungsschutzgerät Typ 2 40kA 2+0 1+1

SD20RS  Type 2


  • SPD Type 2
  • Max. Operating Voltage:
    385 VAC (2+0)
    L-N: 385 VAC, N-PE: 255 VAC (1+1)
  • Nominal Discharge Current:
    20kA / max. 40kA
  • Modes of Protection:
    2+0(L/N-PE)
    1+1(L-N, N-PE)

SD20S  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage:
    L-N: 385 VAC, N-PE: 255 VAC
  • Nominal Discharge Current:
    20kA / max. 40kA
  • Modes of Protection:
    3+1 (L-N, N-PE)

SD20RS   Type 2


  • SPD Type 2
  • Max. Operating Voltage:
    385 VAC (4+0)
    L-N: 385 VAC, N-PE: 255 VAC (3+1)
  • Nominal Discharge Current:
    20kA / max. 40kA
  • Modes of Protection:
    4+0(L/N-PE)
    3+1(L-N, N-PE)
Überspannungsschutzgerät Typ 2 40kA 3+1Überspannungsschutzgerät Typ 2 40kA 2+0 1+1

SD20H270A203-DC  Type 2


  • SPD Type 2
  • System Voltage: 270 VDC
  • Max. Operating Voltage:
    300 VDC (2+0)
  • Nominal Discharge Current:
    20kA / max. 40kA
  • Modes of Protection:
    + — -, - — PE

SD20H230A404  Type 2


  • SPD Type 2
  • System Voltage: 230 VAC
  • Max. Operating Voltage:
    L-N: 275 VAC, N-PE: 255 VAC
  • Nominal Discharge Current:
    20kA / max. 40kA
  • Modes of Protection:
    3+1(L-N, N-PE)

SD25TxxxL100  Type 1+2


  • SPD Type 1+2
  • System Voltage: 120 - 600 VAC
  • Max. Operating Voltage:
    150 - 680 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    1+0(Ld - Ld)
Überspannungsschutzgerät Typ 2 40kA 3+1Überspannungsschutzgerät Typ 2 60kA DC + PE

SD25TxxxA203, Type 1+2


  • SPD Type 1+2
  • System Voltage: 120 - 230 VAC
  • Max. Operating Voltage:
    150 - 550 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    1+1(L-N, N-PE)

SD25TxxxL205, Type 1+2


  • SPD Type 1+2
  • System Voltage: 120 - 480 VAC
  • Max. Operating Voltage:
    150 - 550 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    2+0(L / N - PE)

SD25TxxxL306, Type 1+2


  • SPD Type 1+2
  • System Voltage: 120 - 600 VAC
  • Max. Operating Voltage:
    150 - 680 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    3+0(L-PE)
Überspannungsschutzgerät Typ 1+2 50kA 2+0Überspannungsschutzgerät Typ 1+2 50kA 1+1

SD25TxxxL405, Type 1+2


  • SPD Type 1+2
  • System Voltage: 120 - 680 VAC
  • Max. Operating Voltage:
    150 - 690 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    4+0(L/N-PE)

SD25TxxxL306, Type 1+2


  • SPD Type 1+2
  • System Voltage: 400 - 1000 VAC
  • Max. Operating Voltage:
    880 - 1000 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    3+0(L-PE)

SD25TxxxA404, Type 1+2


  • SPD Type 1+2
  • System Voltage: 120 - 400 VAC
  • Max. Operating Voltage:
    L-N: 150 - 385 VAC
    N-PE: 255 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    3+1(L–N, N-PE)
Überspannungsschutzgerät Typ 1+2 50kA 3+0Überspannungsschutzgerät Typ 1+2 50kA 4+0

SD25TxxxA301/L302, Type 4CA


  • SPD Type 4CA
  • System Voltage: 120 - 480 VAC
  • Max. Operating Voltage:
    L - N: 150 - 385 VAC
    N- PE: 255 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    L1/L2/N-G; L1/L2-N, N-G

SD25TxxxL201, Type 4CA


  • SPD Type 4CA
  • System Voltage: 120 - 480 VAC
  • Max. Operating Voltage:
    150 - 320 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    2+0(L1-G, L2-G)

SD25TS Serie, Type 1+2


  • SPD Type 1+2
  • System Voltage: 480 - 1000 VAC
  • Max. Operating Voltage:
    690 - 1300 VAC
  • Nominal Discharge Current:
    25kA / max. 50kA
  • Modes of Protection:
    1+0(Ld-Ld)
    3+0(L-PE)
Überspannungsschutzgerät Typ 4CA 50kA 2+0Überspannungsschutzgerät Typ 4CA 50kA L1/L2/N-G; L1/l2-N, N-GÜberspannungsschutzgerät Typ 1+2 50kA 1+0 3+0Überspannungsschutzgerät Typ 2 40kA 4+0 3+1Überspannungsschutzgerät Typ 2 40kA 4+0 3+1Überspannungsschutzgerät Typ 1+2 50kA 1+0Überspannungsschutzgerät Typ 1+2 50kA 3+0Überspannungsschutzgerät Typ 1+2 50kA 3+1

SPD for Low-voltage Power Systems

Our surge protection devices (SPD) are suitable for lightning & surge protection of low-voltage systems, power supplies, communication networks, PV systems and street/outdoor lighting.

They meet the requirements of UL 1449 Forth Edition and IEC/EN 61643-11.

Depending on the design, they can be mounted on DIN rails in control cabinets, combiner boxes or optimized for installation in street lights.

They are fail-safe, have an fault display and a remote signaling contact.

They are robust and well protected against harsh environmental conditions and meet the requirements for high reliability in important areas.

Überspannungsschutzgerät Typ 2 60kA 2+0 Überspannungsschutzgerät Typ 2 60kA 1+1 Überspannungsschutzgerät Typ 2 60kA 4+0


α Therm


Alpha Therm GmbH - Your specialist for temperature-dependent

electronic components and circuit protection

Phone: [+49] 6202 / 575688 - 0

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Phone: +49 6202 / 575688 - 0

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