I have a Surge Guard. It makes no sound. It's been plugged into the side of my garage since I bought it (September 2013). It's been through torrential rain, torrential snow, sub-zero temperatures, and high heat (in September), and still works perfectly fine. Here it is on the side of my garage where it plugged in 24 x 7 (since September), except when camping.
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Here's a photo of our camper and how I set up the Surge Protector. Look at the photo and see if you can tell where it is?
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Give up? I run a 25 foot 30 amp extension from the electric pedestal, under the trailer, to the wheel well on the door side of the camper. I then plug in the protector. I then run the trailer cord to the wheel well and plug it into the protector.
First, someone passing by will not see the protector hanging from the electric campground pedestal because it's not there.
Second, you really have to make an effort to see it under the wheel well. And if someone attempts to steel it, they have to be pretty bold to climb around under and around the camper to wedge it out from on top of the wheel.
Now that you know, here's a blow-up of the same photo. Although not 100% theft proof, it's portability is perfect for us.
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