Square D by Schneider Electric HEPD25 Universal Whole House Surge Protection Device, 1-Phase, 3-Wire for 120/240V, 25kA, Black

One of the best you can buy for the price! Installed easy and includes a lit indicator. Highly recommend for adding another layer of surge protection for the house

Installed this Type 1 SPD in a Square D Main panel (will work with any panel with 1/2” knock outs) using the Direct method to L1/L2 posts below Main breaker as per device instructions. The Direct method Saves needing/using a dedicated breaker or wiring to existing breaker in panel. If mounting the SPD to the Main breaker lugs you will need to turn off the Main breaker when changing the SPD out if it fails after a surge. If using a separate breaker you only need to turn that single breaker off to change the SPD. I don’t gamble and always turn off the Main breaker when working on a panel so Direct wiring to L1/L2 is no issue for me. If you are electrically savvy, it’s a 15 minute job (using Direct method), 30 minutes if you aren’t. If you need to move breakers to get an open spot under the main you’re probably looking at an hour depending on how many you need to move. Understand that no Surge Protection Device protects from a direct lightning strike to your home. You should use SPD’s (Type 2) on each sub panel and quality outlet surge protectors at home electronics device outlets. Layered protection is best. Using a single SPD is a gamble.

Installed four for family over the holidays, this was the only one of the external units, since all but 2 breaker slots were occupied, and never throwing away the final 2 expansions!Installation was trivial, even bolted to the backplane bolts (see instructions for that detail). A 2 lug breaker/dummy isn't necessary, however, leave extra length for the 2 hot leads, and have someone experienced with working in panels made those 2 connections.Presuming you know how to connect ground and neutral safely in a circuit panel, you would later be able to power down the whole panel, cut the hot leads with enough excess length to wire nut the replacement unit's hot leads to the original wires when your initial suppressor has fried. You shouldn't need to clamp into the bus bars ever again.This needs to sit outside the panel, and the deepest 1/2" punch outs closest to the wall might not leave enough room for the box, we used a middle punch out. I used an extra threaded conduit nut on the inside and outside of the panel box so the surge suppressor case itself wasn't stressed. The green light is very reassuring that the panel is hot and surge suppression is active, but you might need a bit of electrical tape to cover if it is mounted in a bedroom or similar. If this can't be mounted directly to a panel because it is embedded in the wall, then order their recommended mounting kit, you won't regret it. (We were lucky and didn't need it.)

Added this as the first layer of protection to all of my electrical devices in my house. Still have surge protectors near some devices.

This unit will work with pretty much any mfg. breaker box.Square D reputation and reliability is stellar.80KVA is probably the minimum size to use for whole house surge protection. It won’t protect “better”, but because they are sacrificial units they will last longer before needing to be replaced.This unit is designed for AC power line protection only.Units that protect cable & phone will require (re)running those lines to your breaker box. I didn’t want to do that.Unless you are installing outdoors, the NEMA rating really doesn’t matter.Install is generally straightforward, but is a little “fussy”. Read the directions!Remember to shut off your main breaker 1st and note that the input lugs are still always hot.The Hot lines should be connected as close as possible to your 1st two circuit breaker circuits.The unit should be installed as close as possible to the chosen breaker.Keep your lines as short as possible- no loops or kinks. If possible, twist your leads.The leads are long 30”), heavy gauge, and pretty stiff. Maybe from the way they are compactly wound for packaging.The only glitch I had was that the unit didn’t want to work when I 1st powered things up.The second power cycle was the charm and it’s been up ever since.

While I preferred the surge protector to be inside the panel box, my Square D panel box was 30 years old and did not have the newer 'plug on neutral bar.' This surge protector was the alternative. While there was a little more work to install it (cutting holes, running wires, sheet rock repair and paint), I completed it in a couple of hours. Decided on a whole house surge protector after my washing machine was affected by a power surge and needed a $300 part. If you think about it, most appliances, your furnace, TVs, etc. all have vulnerable and expensive circuit panels and most are not surge protected. Probably why the electrical codes in most states now require whole house surge protectors to be installed.