Type 2 whole-house SPD
Siemens BoltShield FSPD140
Siemens' current flagship residential SPD — 140 kA, 20 kA nominal discharge, audible alarm, and the strongest warranty terms in the group.
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Best for
The default whole-house pick on any brand of panel
Specifications
| SPD Type | Type 2 (UL 1449 5th Ed.) |
|---|---|
| Surge capacity | 140 kA |
| Nominal discharge (In) | 20 kA |
| VPR | 700 V L-N / 700 V L-G / 700 V N-G / 1200 V L-L |
| SCCR | 200 kA |
| Enclosure | NEMA 4X polycarbonate |
| Indicators | Status LEDs + red alarm LED + audible alarm |
| Warranty | 10 years, $100,000 connected equipment |
Specifications as published by Siemens. Confirm against the current spec sheet before buying — manufacturers revise models without renaming them.
What's good
- 20 kA nominal discharge rating — comfortably above the 2023 NEC 242.10 dwelling minimum
- Audible alarm and ground-reference monitoring, so a failed unit announces itself
- Mounts beside any manufacturer's load center, not just Siemens panels
What's not
- Successor to the discontinued FS140 — retailers still sell the old model, so check the box says FSPD140
- External mount needs a knockout and a 2-pole breaker's worth of electrician time
Our verdict
The spec sheet leads the residential group in every column that matters — In, SCCR, enclosure, indication and warranty. If you're having exactly one device installed at the panel, this is the one to name to your electrician.
Compare with the alternatives
- Eaton CHSPT2ULTRA — a lifetime-warranty alternative at the top of the market
- Square D HEPD80 — the proven value pick, especially on square d panels
- Leviton P2120-B — service-entrance installs and meter-adjacent mounting
- Intermatic AG3000 — adding a protection layer at the ac condenser or heat pump
- Tripp Lite by Eaton ISOBAR6ULTRA — the point-of-use layer at your electronics