Surge Protector

[rprochnow]

We have an ATS with builtin surge protector plus we use a Hughes autoformer and Progressive EMS.

When the surge protector blew in our autoformer, we could still power the coach by disconnecting the autoformer, and was able to replace the surge protection circuit in a few days.

Recently our ATS went out, and that prevented us from getting shore or generator power and required replacing the ATS (ATS failed shortly after hurricane power failure, even with having it connected through the autoformer and EMS).

The ATS was much harder and more expensive to replace. Even though the autoformer and EMS didn't protect the ATS this time, we still prefer the extra protection because the external devices can be bypassed or replaced more easily and at lower cost.

[FLRVingBob]

As an electrical engineer who deals with this issue on a regular basis, while an onboard/inboard protector seems like a good idea and may appear to make your life “lazier”, one thing is for sure, once a significant spike/surge is “in the door” so to speak, all bets are off. The way coaches are wired, there are many possibilities for a strike never to make it to the device and cause massive damage. Typically transfer switches are ahead of the device and will get damaged. With the transfer switch ahead of the device, the generator is also at risk. A large enough strike, the surge can actually depart the cable seeking any source of a ground….even a water connection. Lightning and the potential surges it generates is a nefarious living entity that can defy all precautions.

Understand that multiple protection devices is a good thing. Modern MOV and Gas Tube based devices are cumulative. That is, a protector at the pedestal, in front of the cable is one layer. If you have a booster with protection, one more layer and if you have inboard in addition to the outboard, you now have three layers of “cumulative” protection. Fact is I would NEVER plug into a power source without protection at that source, even in my own driveway. If you are worried about theft, get a safety cable and lock. $150 for a decent outboard unit is cheap insurance…..a surge that goes unchecked can coast you thousands…..up to and including fire if the conditions are right…..

[DarkSideJeep]

Originally Posted by FLRVingBob

As an electrical engineer who deals with this issue on a regular basis, while an onboard/inboard protector seems like a good idea and may appear to make your life “lazier”, one thing is for sure, once a significant spike/surge is “in the door” so to speak, all bets are off. The way coaches are wired, there are many possibilities for a strike never to make it to the device and cause massive damage. Typically transfer switches are ahead of the device and will get damaged. With the transfer switch ahead of the device, the generator is also at risk. A large enough strike, the surge can actually depart the cable seeking any source of a ground….even a water connection. Lightning and the potential surges it generates is a nefarious living entity that can defy all precautions.

Understand that multiple protection devices is a good thing. Modern MOV and Gas Tube based devices are cumulative. That is, a protector at the pedestal, in front of the cable is one layer. If you have a booster with protection, one more layer and if you have inboard in addition to the outboard, you now have three layers of “cumulative” protection. Fact is I would NEVER plug into a power source without protection at that source, even in my own driveway. If you are worried about theft, get a safety cable and lock. $150 for a decent outboard unit is cheap insurance…..a surge that goes unchecked can coast you thousands…..up to and including fire if the conditions are right…..

Thanks for the support.

[darrellr]

Originally Posted by FLRVingBob

As an electrical engineer who deals with this issue on a regular basis, while an onboard/inboard protector seems like a good idea and may appear to make your life “lazier”, one thing is for sure, once a significant spike/surge is “in the door” so to speak, all bets are off. The way coaches are wired, there are many possibilities for a strike never to make it to the device and cause massive damage. Typically transfer switches are ahead of the device and will get damaged. With the transfer switch ahead of the device, the generator is also at risk. A large enough strike, the surge can actually depart the cable seeking any source of a ground….even a water connection. Lightning and the potential surges it generates is a nefarious living entity that can defy all precautions.

Understand that multiple protection devices is a good thing. Modern MOV and Gas Tube based devices are cumulative. That is, a protector at the pedestal, in front of the cable is one layer. If you have a booster with protection, one more layer and if you have inboard in addition to the outboard, you now have three layers of “cumulative” protection. Fact is I would NEVER plug into a power source without protection at that source, even in my own driveway. If you are worried about theft, get a safety cable and lock. $150 for a decent outboard unit is cheap insurance…..a surge that goes unchecked can coast you thousands…..up to and including fire if the conditions are right…..

Installed properly, the only difference between the portable plugged into the pedestal and the hardwired one in your coach is that they are on opposite ends of the same wire. As an electrical engineer - how does this logic you provided make sense?

[NXR]

Originally Posted by darrellr

Installed properly, the only difference between the portable plugged into the pedestal and the hardwired one in your coach is that they are on opposite ends of the same wire. As an electrical engineer - how does this logic you provided make sense?

Agreed. Perhaps he's thinking of power strips inside the coach.

And plain old surge protectors are about worthless because a lot of electrical and electronic equipment already have MOVs built in because they're so cheap. Want to double the joules of protection? Double the number of $1 (in bulk) MOVs. They are a massive profit generator.

But a device that detects wiring and power faults and kills the power automatically? Or never allows the power to flow? That's a good thing and that's what I use.

People who say "I always use a surge protector and I've never had a failure" are trying to prove a negative. They have no idea if the same result would have been achieved if they had saved their money.

Ray