DC Isolator Switch

DC Isolator Switch for Solar PV Systems

A DC isolator switch disconnects the direct-current side of a solar PV system so installers can safely isolate PV strings, inverters or combiner boxes during maintenance. For solar applications, choose a DC-rated isolator with the correct voltage, current, polarity, breaking capacity and IEC 60947-3 compliance.

ETEK supplies DC isolator switches for residential, commercial and utility solar PV applications, including 1000V DC and 1500V DC systems. Options cover common current ratings from 32A to 125A for PV strings, combiner boxes, inverter inputs and maintenance isolation.

How to choose a DC isolator switch

• Match the isolator voltage rating to the maximum PV string voltage: 1000V DC or 1500V DC.
• Choose the current rating according to string current, parallel strings and safety margin.
• Use DC-rated switching devices designed for arc extinguishing under direct current.
• Check IEC 60947-3 compliance, enclosure rating and installation location.
• For OEM projects, confirm handle type, pole configuration, wiring direction and labeling requirements.

DC Isolator Switch FAQ

What is a DC isolator switch used for?

A DC isolator switch is used to disconnect the DC side of a solar PV, battery or EV system for maintenance and emergency isolation.

Do solar PV systems need a DC isolator?

Most solar PV installations require a DC isolation device near the inverter or combiner box according to local electrical rules and system design.

What voltage rating should a solar DC isolator use?

Common solar systems use 1000V DC or 1500V DC isolators. The isolator rating must be equal to or higher than the maximum PV string voltage.

Is a DC isolator the same as an AC isolator?

No. DC current is harder to interrupt because it has no natural zero crossing, so a DC isolator needs a DC-rated arc extinguishing design.

Where should a DC isolator be installed?

It is typically installed between PV strings or combiner boxes and the inverter, in a location accessible for maintenance and emergency shutdown.

Can ETEK supply OEM DC isolator switches?

Yes. ETEK supplies DC isolator switches for solar PV systems with wholesale and OEM options for distributors, installers and equipment manufacturers.