Image reference
Solar PV protection
PV & DC surge protection
Surge Protective Device
WILLING supplies surge protective device options for solar PV DC strings, combiner boxes, inverter DC inputs and electrical protection panels.
Use this page to compare application context, SPD selection factors, installation workflow and the meaning of key electrical parameters before requesting a model-specific datasheet.
Reference status: Values transcribed from supplied product images require confirmation against the current model datasheet and certification scope.
SPD product range
Surge protection configurations for PV and electrical systems.
Confirm circuit type, maximum continuous voltage, pole configuration, discharge ratings and documentation before final product selection.
Image reference
Image reference
Three-pole arrangement
3P DC SPD
Three-module PV DC configuration shown for system and procurement review.
Configuration reference
Four-pole arrangement
4P DC SPD
Final DC electrical configuration, product image and model ratings must be confirmed before quotation.Engineering parameters
Understand the ratings before comparing SPD models.
Uc1000 V DC
385 V ACMaximum continuous operating voltage shown across supplied images
385 V ACMaximum continuous operating voltage shown across supplied images
In20 kANominal discharge current at the stated 8/20 µs waveform
Imax40 kAMaximum discharge current at the stated 8/20 µs waveform
Up≤ 1.8 kVVoltage protection level shown on the supplied product images
TypeT2Type 2 marking visible on the supplied product images
Important: These values are not presented as a universal WILLING series specification. Request the current datasheet, connection diagram and document scope for the exact model being evaluated.
Application workflow
Select, install and maintain an SPD as part of the system design.
Final device selection should be completed by a qualified electrical professional using the project single-line diagram, risk assessment and local requirements.
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01
Select AC or PV DC
Identify the circuit side first. A PV-rated DC SPD and an AC SPD are not interchangeable.
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02
Confirm system voltage
Check maximum continuous operating voltage, PV open-circuit conditions, system topology and environmental limits.
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03
Define the protection point
Coordinate protection at the combiner box, inverter input or AC distribution point according to the project design. Use the PV combiner box engineering guide when reviewing enclosure-level DC protection.
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04
Install with controlled conductor routing
Keep connection paths short and follow the approved wiring diagram, earthing design and manufacturer instructions.
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05
Inspect indicator status
Include visual status, terminal condition and replacement criteria in commissioning and scheduled maintenance.
Standards and compliance review
Use the applicable standard for the circuit and project scope.
A standard reference is not a product compliance claim. Verify valid test reports, declarations and the exact model scope before approval.
| Reference | Scope | Engineering use |
|---|---|---|
| IEC 61643-31:2018 | Requirements and test methods for SPDs used on the DC side of photovoltaic installations. | PV DC product and document review. |
| IEC 61643-32:2017 | Selection and application principles for SPDs connected to the DC side of PV installations. | System selection, placement and coordination review. |
| IEC 61643-11:2025 | Requirements and test methods for SPDs connected to AC low-voltage power systems. | AC-side SPD evaluation. |
The supplied product images display GCL-40, GB/T 18802.11, T2, CE and TUV-related markings. Treat all markings as reference until the current certificate, declaration and exact model coverage are confirmed.
Engineering questions
Surge Protective Device FAQ
Concise answers for EPC, installation and procurement review.What does an SPD do in a solar PV system?
A surge protective device limits transient overvoltage and diverts surge current away from sensitive equipment. It supports protection of PV strings, combiner boxes, inverter inputs and AC distribution equipment, but it does not replace overcurrent protection or system earthing.
Where should a DC SPD be installed in a PV system?
The installation point depends on the PV system architecture and risk assessment. Common locations include the DC combiner box and inverter DC input. Conductor routing, coordination and earthing must follow the project design, applicable standards and the SPD manufacturer's instructions.
What do Uc, In, Imax and Up mean on an SPD?
Uc is the maximum continuous operating voltage. In is the nominal discharge current. Imax is the maximum discharge current for a Type 2 SPD under the stated test waveform. Up is the voltage protection level measured under defined test conditions.
How do I choose between an AC SPD and a DC SPD?
Match the SPD to the circuit side, voltage, current characteristics and system topology. Use a PV-rated DC SPD on the photovoltaic DC side and an AC-rated SPD on the AC distribution side. Do not use an AC-only SPD in a PV DC circuit.
Is a Type 2 SPD sufficient for every solar installation?
Not always. SPD type and coordination depend on lightning exposure, the external lightning protection system, cable routing, installation category and the project risk assessment. Some projects may require Type 1 or combined Type 1 and Type 2 protection.
How should an SPD be inspected and maintained?
Inspect the status indicator, terminals, protective conductor path and signs of heat or damage during scheduled maintenance and after significant surge events. Replace a failed module according to the manufacturer's instructions and verify the circuit is isolated before service.
Project inquiry