Surge Protector

[moosetags]

I was just reading a thread on RV.net forums that is talking about RV surge protectors. It started me thinking that I might need one.

I'm throwing this out here on Airforums to what the consensus is here. I have never had a surge protector for Lucy. We have spent over 1,000 nights in Lucy at several hundred different campgrounds.

Do I need a surge protector, and what type do I need? What are all the other Airstreamers using?

Brian

[Protagonist]

This subject has come up more than once on the Forums, and opinions are divided. I would say that from your own vast experience without one, you probably don't need one.

I have one, and use it religiously (get down on my knees to plug it in, then pray). A surge protector protects you from exactly ONE surge, then you throw it away and buy another. So, if it never stops a surge, I've wasted my money. If it does stop a surge, I'd rather buy another surge protector than replacement appliances. So, I'm in the "better to have it and not need it, than need it and not have it" camp.

As for type, given its throwaway nature, even if you decide to get one, don't spend big bucks on it unless you're protecting something even more valuable. I got mine at my local Route 66 RV parts store; it's a Progressive Industries SSP-30, regular price $99. I bought mine on sale for a bit less.

[Jammer]

Hi Brian.

This comes up from time to time here and on other RV-related forums.

I have a background in physics and electrical engineering though these days I write software for a living.

There are two types of surge protectors for RVs that are on the market. The cheap ones are nothing more than a set of MOVs (metal oxide varistors) connected between power and ground. Those will provide some protection against lightning strikes.

The thing is that shore power connections run underground and are generally supplied by pad-mounted transformers which provide enough inherent protection against lightning that any lightning-related surge will, by the time it gets to your trailer, be weak enough that any electronics you might have present can deal with it. Good quality power supplies have their own MOVs or are otherwise designed to deal with voltage spikes.

At one of my last jobs we had a lab where there was a big red power outlet with warning signs on it and a button you could push to apply surges of varying voltages and durations to it. We tested new products on it just to be sure. We also had, on a similar piece of equipment. an insulated wand designed to provide a carefully calibrated 10,000 volt pulse to whatever it touched, and we'd apply it to all exposed connectors and surfaces.

So I would say that the cheap MOV-only surge protectors don't solve any problem RVers actually have, unless you stay in one of the few remaining campgrounds where the shore power comes to the pedestal via overhead wires.

The autotransformer-type surge protectors additionally provide some compensation for slightly low and high voltage. Hughes Autoformer is the best known brand. These will also disconnect power if the voltage is out of specification. They are heavy and expensive.

In general the input voltage range of the autotransformer devices isn't any wider than what the converter and 120v appliances can accept by themselves. In practice the converter, fridge, microwave, and air conditioner will all run fine on any input voltage between around 100 and 135 volts. I know, I've done it.

The autoformer devices will detect and correct certain overvoltage conditions that result from wiring problems in the campground or in the utility equipment serving the campground. These problems are rare.

I don't recommend surge protectors of any type as I think that the weight, hassle, and dollar cost exceeds the value of the protection they provide.

If you're concerned about your electronics, the best thing to do is run all the electronics from the 12 volt system. The converter and 12v batteries provide much better surge protection, for equipment connected to the 12v system, than even the fancy surge protectors provide for the 120v system.

If you're concerned about damaging your converter, consider replacing it with a Xantrex Truecharge, which is designed to run on any voltage from 90-265 and will shut off by itself if the voltage is too low.

RV technicians like to blame air conditioner failures on "power surges" or low voltage. They find it much more convenient than blaming such failures on shoddy design and workmanship on the part of the manufacturer of the air conditioner. Air conditioners have thermal protectors in them which should prevent damage from undervoltage. Again in practice they'll work fine up to 135 volts or so, maybe more.

I don't have a surge protector on my trailer and doubt if I will ever get one.

[BrandonJenna]

I have a question for Jammer, I have my trailer plugged into the 125 volt outlet I had installed at my sister's house. When I am in the trailer (2012 27FB) watching a movie off my playstation 3 with a 750 watt heater going sometimes all of the AC outlets shut off. I have checked the shore cord to see if the blue led is on or off because maybe it originated from the house but it is still on. It is always when I draw "too much" power. The outlets usually remain unusable for about 5-10 minutes before they auto-magically come on. No fuses are burned nor breakers tripped in the Converter.
Why would this happen? What is happening, I would love to know what really is happening? I'm I truly using too much power? And should I have it looked at by the dealership? Thanks!

[xrvr]

How many amps is that wall outlet? Might be too low. You need 20 amp at least. jim

[Jammer]

Brandon

I would start by re-torquing all the connectors in the 120v breaker panel area (with shore power disconnected, of course, for safety). That's usually it. If not you might have a bad cord or a loose connection where the cord attaches to the trailer.

[TBRich]

As noted above, there is a lot of difference of opinion in this area... We all have used surge protectors in various applications in our homes, etc, and for the most part, they have never come into play. Call me over-protective, but it just makes sense to us to take this simple precaution ... and we feel it's easier to replace a surge protector if it blows than to replace damaged appliances, etc.

We used to have one of the ~$99 models for our Bambi until one hot day in the summer while running the AC, the female end of the protector and the male end of our shore line decided to overheat and begin to melt. Luckily I noticed it and disconnected them before there was a serious issue...having to replace the male end of the shore line and the surge protector was bad enough. Granted, I am not sure what was going on in that particular situation...it may have been a poor connection or a number of other things, but when I went to replace the surge protector I did more thorough research and realized that the protector we had been using was most likely inadequate for the task and was more suited to pop-ups, etc where there are fewer appliances and electronics aboard...and that a larger, more powerful protector was in order.

We ended up getting a Surge Guard 32730 which is geared to 30-amps and has more protections/features than the one we were previously using. It was not cheap and it is a bit bulky, but I seems worth it to us.

Shortly after we got it we were in a park where we had camped several times. While watching movie one night all of a sudden the power went out. I went to investigate and sure enough, the surge protector had interrupted the current and disconnected our rig from the power source. Curious as to why, I plugged the shore power line into the post outlet and discovered the voltage had dropped significatnly below acceptable ranges. So the surge protector had done one if it's jobs... I reinstalled it and when the current was within acceptable ranges again, it reconnected and we were good to go. We would never have known that this was happening without the protector unless we sat there staring at the voltage meter plugged into an outlet all evening. We have no idea why the voltage dropped, but it happend for 4 nights in a row at this park.

So my money is on making use of a surge protector and taking that extra bit of precaution.

[Airtandem]

I have and use the same on that TB has. I bought it after I saw the campground host's trailer get nailed by a surge. ??? only effected the power cord?? We found several other outlets in the park damaged also.
My thought is that I carry insurance on the AS for accidents,why not electrical also.
IT ONLY TAKES ONCE.

[dsrtgrls]

being a good sam member went to campingworld site and pulled the trigger on the above mentioned surge protector as it was on sale and free shipping. i use them in the home to protect stuff so why not the trailer. we do get lightning strikes as one of my neighbors experienced and i do leave the tt plugged in to the house unless i know when a storm is coming to unplug. now i will have a little more peace of mind at home as well at the campground. thanks for the discussion.

[Bluto]

Originally Posted by moosetags

I was just reading a thread on RV.net forums that is talking about RV surge protectors. It started me thinking that I might need one.

I'm throwing this out here on Airforums to what the consensus is here. I have never had a surge protector for Lucy. We have spent over 1,000 nights in Lucy at several hundred different campgrounds.

Do I need a surge protector, and what type do I need? What are all the other Airstreamers using?

Brian

Here's the one I use. Check out this link. Then find the best price. Was able to get mine on sale last year.
EMS-PT30C

[NevadaGeo]

Just a curious question, do these (or any) surge protectors protect from the neutral becoming "hot"? I've had that situation in this house more than once: Tree falls on the power service on the house side of the meter pole. One of the hot wires breaks and then contacts the neutral, which energizes the neutral side of all the appliances in the house, bypassing the ground wire at the breaker box on the house. Most appliances don't like the neutral to be hot. Electric company replaces the appliances. Next storm, tree falls on the power service on the house side of the meter pole.... got the appliances zapped twice, maybe three times. The surge protectors I've seen only protect on the "hot" side...Chain saw all the century old Lombardy Poplar trees that stood after dying for a dozen years, but would come down with a strong South wind.

[NevadaGeo]

And it seems quite possible for an umbilical or camp ground power to become cross wired, giving you a hot neutral wire to the trailer.

[Friday]

I would agree with jammer's assessment, if you knew the quality of the wiring you were dealing with. We had some sketchy issues hooking up in Vegas with our pad, and you'd assume with 500 other RV's on site things would be pretty solid... not so.

Don't forget generators back-feeding into the system as well...

[ROBERTSUNRUS]

Hi, I bought one of these [see picture] and I have only used it a few times. I only use it when there is a thunderstorm. Basic, simple, and in-expensive.

[GetOutDoors]

It's not just surges that concern me.... You could plug into 240 unaware. This thing does much more that just surge protection: http://www.progressiveindustries.net/ems_hw30c.htm

And another tread on this topic: http://www.airforums.com/forums/f199...tor-83648.html

[Jammer]

Originally Posted by NevadaGeo

Just a curious question, do these (or any) surge protectors protect from the neutral becoming "hot"?

Some of the autotransformer-type ones do, as part of their proofing of the supply voltage before turning everything on.

You can also check manually with one of those little three-light ground testers before you plug in. I have one in the shore power compartment of my trailer but hardly ever use it.

I've had that situation in this house more than once: Tree falls on the power service on the house side of the meter pole. One of the hot wires breaks and then contacts the neutral, which energizes the neutral side of all the appliances in the house, bypassing the ground wire at the breaker box on the house. Most appliances don't like the neutral to be hot. Electric company replaces the appliances. Next storm, tree falls on the power service on the house side of the meter pole.

In the North American wiring tradition, neutral and ground are bonded together at the service entrance in residential wiring. Grounding practices elsewhere are different. One disadvantage of the North American way of doing things is that a short between hot and neutral in the distribution system also causes high ground currents to flow and that's what causes the damage.

RVs aren't wired that way -- the ground is isolated from the neutral.

A properly wired RV set up for 30a service won't be affected by reversal of neutral and hot, except that the safety advantages that come from switching the hot instead of the neutral would be lost.

Originally Posted by GetOutDoors

It's not just surges that concern me.... You could plug into 240 unaware. This thing does much more that just surge protection: EMS-HW30C

I think the problems with open neutrals in the campground wiring are really the only plausible reason to have any sort of power conditioning. Open neutrals can show up under heavy load as a result of poor wiring practices and lead to severe under and over voltage at the pedestal. Depending on the situation you could conceivably damage anything that isn't prepared to deal with 240 volts and that is actually drawing power while you're plugged in.

That's one of the reasons I like the TrueCharge converter. It would ride through something like that because of the wide input voltage range.

That leaves the air conditioners, fridge, water heater, and microwave.

The water heater would pop a breaker on 240v before damaging anything.

The fridge will blow the internal fuse if present or require a new element if not. Either way you can still run it on gas until repairs can be made.

Air conditioners would probably be OK because it's so unlikely to get way over 120v as a result of an open neutral while the air conditioners are running because of the symmetry of the load though it is possible that there will be fan motor or compressor damage if they do.

No idea on the microwave. They are inverter designs internally and not usually very picky about voltage.

So, sure, the possibility of damage is there, and open neutrals though rare do sometimes occur. Technically it's the campground's responsibility to pay for repairs (or their insurer's) but I realize that it's nearly impossible to collect on a claim like that.

Most RVers will travel for a lifetime without running into problems like this.

I'd rather take my chances than pay the upfront cost weight and hassle of one of the expensive power conditioners. Remember that the cheap ones don't help with this.

[Jammer]

Originally Posted by TBRich

We used to have one of the ~$99 models for our Bambi until one hot day in the summer while running the AC, the female end of the protector and the male end of our shore line decided to overheat and begin to melt.

Combination of poor quality female connector on the surge thingy and a little corrosion on the shore power line, probably. I try hard to avoid extra connections because of this sort of thing. Without the surge thingy you would have been fine. ::shrug::

...[it] seems worth it to us.

Shortly after we got it we were in a park where we had camped several times. While watching movie one night all of a sudden the power went out. I went to investigate and sure enough, the surge protector had interrupted the current and disconnected our rig from the power source. Curious as to why, I plugged the shore power line into the post outlet and discovered the voltage had dropped significatnly below acceptable ranges. So the surge protector had done one if it's jobs... I reinstalled it and when the current was within acceptable ranges again, it reconnected and we were good to go. We would never have known that this was happening without the protector unless we sat there staring at the voltage meter plugged into an outlet all evening. We have no idea why the voltage dropped, but it happend for 4 nights in a row at this park.

This story is very common and sells lots of these things.

The problem is, though, that chances are that the voltage wasn't off by enough to really matter. The "acceptable range" outside which the surge protectors will pitch a hissy fit is deliberately chosen to be narrow by the manufacturers of the devices to convince their customers that the devices are worthwhile.

[GetOutDoors]

Originally Posted by Jammer

That leaves the air conditioners, fridge, water heater, and microwave.

... and the flat screen, and any other custom electrical device not powered by the converter.

When it comes right down to it, an Electrical Management System (which includes surge protection) is like insurance: you don't have the need until the unexpected happens.

We all buy insurance, some paying more for better coverage - all based on our assets and comfort zone there of ....

Only having surge protection is like having only theft coverage on your insurance policy: it doesn't cover collision or fire.

[TBRich]

Originally Posted by Jammer

Combination of poor quality female connector on the surge thingy and a little corrosion on the shore power line, probably. I try hard to avoid extra connections because of this sort of thing. Without the surge thingy you would have been fine. ::shrug::



This story is very common and sells lots of these things.

The problem is, though, that chances are that the voltage wasn't off by enough to really matter. The "acceptable range" outside which the surge protectors will pitch a hissy fit is deliberately chosen to be narrow by the manufacturers of the devices to convince their customers that the devices are worthwhile.

Maybe. Maybe not.

[steverino]

Wow Brian, with 1000 nights so far, and no events which might justify a surge protector, perhaps your the poster boy for the argument that they are unnecessary

But, as Airtandem says, it only takes once. I have a Surge Guard 32730....