We've all got one — a power bar with a little light that says 'surge protected'. It feels responsible. But if you think that $30 strip is genuinely protecting your home theatre setup or your home office equipment from a serious surge event, there's something important you need to know.
What is a power surge, exactly?
A power surge is a sudden, brief spike in voltage above the standard 120V delivered to your home. Anything above about 170V can damage sensitive electronics. Surges can be tiny fractions of a second or they can last longer — but modern electronics don't need much to sustain permanent damage.
The culprits: lightning strikes on or near power lines, utility switching events, large appliances cycling on and off (your HVAC, refrigerator, and dishwasher all create small surges when their motors start), and power grid fluctuations.
Why power bar surge protectors fall short
Point-of-use surge protectors (those power bars with 'surge protection' on the label) use MOVs — metal oxide varistors — to absorb excess voltage and redirect it to ground. The problem is they're designed for small, repetitive surges. After they absorb a certain total amount of surge energy (measured in joules), they're done. They often fail silently — the outlets still work, but the surge protection is gone.
More critically: surge protectors only protect the devices plugged into them. Your dishwasher, fridge, HVAC system, pool pump, and any hardwired equipment get no protection at all.
A lightning strike near your home can send a surge through not just your electrical system, but through your coaxial cable, telephone lines, and internet cables simultaneously. No power bar handles that.
Whole-panel surge protection: how it works
A whole-home surge protector (also called a service entrance surge protector) is installed directly at your electrical panel. It intercepts surge events before they travel into your home's wiring — protecting every circuit, every outlet, every hardwired appliance simultaneously.
Modern whole-home units can handle surge currents of 40,000–80,000 amps — far beyond what any power bar can absorb. They also include status indicators so you know they're still working.
The recommended approach: layered protection
- Layer 1: Whole-home surge protector at the panel ($300–$600 installed) — handles the heavy events
- Layer 2: Quality point-of-use surge protectors ($50–$150) on sensitive electronics — catches anything that gets through
- Layer 3: UPS (Uninterruptible Power Supply) for computers and network equipment — adds battery backup for sags and outages
A whole-home surge protector is one of the best value electrical upgrades a homeowner can make. It protects every appliance in your home for a one-time cost that's a fraction of what a single appliance replacement would cost after a surge event.
Installation takes about an hour and is straightforward for any licensed electrician. It can often be added during a panel upgrade or other electrical work to keep labour costs minimal.
Safer Electric Team
Licensed Electricians · Toronto, ON
Our team of licensed GTA electricians writes these guides to help homeowners make informed decisions. Every article is reviewed for technical accuracy.