WHOLE HOUSE ELECTRICAL SURGE PROTECTION DEVICE

Photo courtesy of Schneider Electric

A Surge Arrestor (NEC® Article 242.18) is “a protection device that limits surge voltage by discharging or passing current.  It prevents continued flow of such current and can repeat that action” — It can be used multiple times.  It operates in electrical systems above 1000 volts. 

For electrical systems 1000 volts or less, a surge protection device (SPD) is used.  A SPD is “a protection device that limits transient voltage by diverting or limiting current.  It prevents continued flow of such current and can repeat that action.”  A Type 1 SPD operates on the line side of the service equipment (Upstream, on the utility side of the service equipment before the main breaker in the main electrical panel or main disconnect). The more common Type 2 SPD operates on the load side of the service (Down-stream, after the main breaker/disconnect).  Other types of SPD’s includes, but are not limited to, Type 3 SPD’s which are found at point of use (Receptacle and powerstrips with surge protection component, not just a multi outlet powerstrip) and Type 4 SPD’s (Metal oxide resisters) are components for manufacture use only.

The Tiny-Off Grid House is designed to independently harvest its own power from renewable solar, wind and hydro energies; away from the hazards often associated from being connected to the utility grid. However, there are still hazards such as surges that can be caused by lightning strikes, static electricity buildup or power hungry appliances such as an air conditioner or a motor . . . for these reasons, a level 2 SPD is necessary. (2020 NEC® 230.67 (A) (B) (C))

Photo courtesy of Schneider Electric

The Schneider Electric HomeLine HOM250PSPD Surge Protection Device will be used to provide type 2 whole house surge protection. It is designed to minimize or dampen transient surges and spikes caused by internal over voltages. It does not directly offer protection from “lightning strikes.” It is also not an “over-current protection device.”

For more information on Lightning Protection, please read “Tiny Off Grid House Lightning Protection.”

For more information on over-current protection devices (Circuit Breaker) please read “Tiny Off-Grid House Over Current Protection Device.”

The Schneider Electric HomeLine SPD, model #HOM250PSPD, is a Plug-on Neutral (PON) SPD that is conveniently installed in the main electrical panel (MEP) without the use of a pigtail. According to Schneider Electric their SPD “provides whole house surge protection for all 120/240 Volts loads fed by the load center where it is installed.” The optimal installation position for most type 2 SPD’s is on the L1 or L2 positions of the main service panel; the first two horizontal positions below the main breaker. There is no known limit to how many SPD’s can be installed in a main service panel.

Please share your thoughts or experiences in the Comments section below.