I use one when allowed and have had absolutely no problems in fact I am currently using mine at the shop to tie two 20 amp circuits together as I live in my coach during the week and have been to busy to have a plug put in. I don't believe that it gives me a full 40 amps but it does allow me to run the fridge, the water heater and one roof ac with no issues.
Quote: How do you damage the pedestal wiring by tying both neutrals together with the cheater box? Aren't "both" the neutals actually just one neutral back to the main at the panelboard? Two hots require one neutral, single phase, no?
It depends on how the pedestal wiring was done. If it is wired as a single phase 120V with wire sized for the 30 amp connector & the 20 amp tapped from it, it will be protected by a 30 amp breaker at the campground's distribution panel, and using a cheater won't hurt anything, but won't give you any more power since the campground's 30 amp breaker is the limit.
If larger wire is run from the campground panel to multiple sites & the pedestal breakers are used to provide the individual receptacle protection there can be a problem. It is possible the tap feeding the pedestal is sized for the largest breaker (30 amps). By using both receptacles, it is possible that you could draw 30 amps from one & 20 amps from the other. If the pedestal is wired as a single phase 120V, the neutral current will be 50 amps since both receptacles are on the same leg & the current is additive. There is no breaker in the neutral, and it would be sized for 30 amps.
If the 30 amp & 20 amp receptacles are on different legs of a single phase 120V/240V service, the neutral currents would be subtractive - using a cheater box won't cause a problem. This would be an unusual way to wire the pedestal if there isn't going to be a standard 50 amp 120V/240V receptacle. The end user can use a multimeter to determine if the two receptacles are on the same or separate legs.
The worst case is where the campground has done multiple wirings over the years. In that case there may be a separate run to each receptacle (the 20 amp & 30 amp) to the campground service. There will be a 50 50 chance that the hots are on opposite legs. In the worst case, they may even run to different services, in which case there may be a voltage difference between the two neutrals making sparks as you plug it in.
If they are on the same leg running to the same service panel, the neutral current will be additive, however how much is carried by each neutral is determined by the resistance of each neutral, not by the wire size. Although it is likely that the larger wire will carry more current, there is no guarantee. Poor connections, a shorter run for the smaller wire, even a broken neutral could cause a problem. Worst case - you might put 50 amps on an unprotected #12 wire. This would be unusual, but possible if the 30 amp neutral was broken. The unknowledgeable end user might even believed he or she "fixed" the 30 amp receptacle since it didn't work by itself because of the broken neutral - the cheater box lets the 20 amp neutral carry the 30 amp current.
Although there are cases where neutrals can be paralleled, it is only allowed where the wire sizes are so large that single wires would be difficult to pull through conduit and code requires they be exactly the same length, size, etc.
Since it is difficult for the non electrician user (or even for electricians) to know how the campground is wired, cheater boxes should be used with care. I don't blame campground owners for banning them - they may appear to work while causing damage to the campgrounds electrical system.
* This post was
edited 04/06/08 11:26am by vermilye *
vermilye wrote: If larger wire is run from the campground panel to multiple sites & the pedestal breakers are used to provide the individual receptacle protection there can be a problem. It is possible the tap feeding the pedestal is sized for the largest breaker (30 amps). By using both receptacles, it is possible that you could draw 30 amps from one & 20 amps from the other. If the pedestal is wired as a single phase 120V, the neutral current will be 50 amps since both receptacles are on the same leg & the current is additive. There is no breaker in the neutral, and it would be sized for 30 amps.
If the pedestal was wired that way, it would be in violation of the NEC. Neutrals must be sized maximum possible current. If they are feeding a 30A plug and 20A plug, the combined neutral must be rated for 50A.
Matthew_B wrote: ....it would be in violation of the NEC.
Even with my limited experience with campground wiring, this would not be a first! LOL
vermilye, thanks for the extensive explanation, you saved me a lot of typing.
Matthew_B, in general, the problem with combining neutrals is that once this is done, the current that travels down a "hot" doesn't necessarily have to travel back through the corresponding neutral. So with a 30A/20A case, as an extreme example, it's possible that the neutral for the 30A might carry all 30 Amps of it's own hot, plus 15A of the 20A's hot. Thus the 30A's neutral would be forced to carry 45A. The breakers won't trip to protect this because the fault is on the neutral.
Putting conductors in parallel can lead to unpredictable results, especially as conductors, connections and receptacles deteriorate with age, use, weather, abuse, etc.
~Rick
2005 Georgie Boy 3625 DS on a Workhorse W-22 (Class A)
Rick, Gail, 1 girl (12-Angel), 1 girl (7), 2 boys (8 & 5), 1 plump Golden Retriever.
2001 Honda Odyssey with Demco Aluminator tow bar & tow plate, SMI Silent Partner brake controller.
While my use didn't cause damage (that I am aware of), I can relate a similar "neutral bonding" situation that did. On my uncle's previous class A, he tried adding in a separate 20A circuit to his 30A rig, basically doing what the cheater boxes attempt to do. He wasn't careful about keeping the neutrals isolated. In this case the problem was the neutrals that were subjected to the extra current were in his RV's main panel. Fortunately, he was tipped off by a burning smell one time and was able to shut things down before any fire damage occurred. He was lucky. But the dark brown neutral wires weren't a pretty sight.
Moral of the story: combining neutrals is not a good idea.
Building a cheater box is not very difficult for anyone who knows about electrical wiring. Basically it uses a 50 amp stove receptacle (same as the RV 50 amp plug) and then uses 2 "Hot" and one netural and 1 ground wire.
The cheater box inside has two #10 gauge power cords coming into it, with both white connected to the netrual connection, the blacks hooked up to the left and right "Hot" connections (but not together) and the greens connected to the ground screw.
A friend had one, and they rented two camping spaces in a park they liked to visit, but only had 30 amp services to the RV's. Then used a 25' extension cord to the site where he parked his truck, and it powered the fifth wheel fine.
It is possible to have problems. Like if one of the receptacles is wired with the netural and hot backwards, then when you plug in and turn on the circuit breaker of both, there will be 30 amps going directly to the netural of the cheater box. So be sure to check the polarity with a checker, like the ones with three little lights.
I have also found that most RV campgrounds have GFI's on the 20 amp receptacle, so you would probably need to rent two spaces to get two non-gfi receptalces. I have only seen a couple of campgrounds with 30 amp GFI's (My motorhome will not be able to plug into a GFI because if it's inverter/charger) and have yet to see a campground with a 50 amp GFI circuit breaker.
It is possible to have a 50 amp GFI circuit breaker, they are used to feed spa equipment and pools in commercial buildings, but the circuit breakers are more than $200!
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a Porsche or Country Coach!
I have one, I have never used it. I tried once but alas the GFCI prevented it
I'm not going to sell it though.. Should I ever find my self in some areas in August.. Well. one park manager lets folks use them during the "Slow Times" (August) cause there is no other way to survive (It's hot there in August)
I have considered the dangers and consider them to be minimal However the places where I can use them are too
The greatest danger is that many parks have a "One to a customer" rule and in those parks if you use a cheater box you may be asked to leave, NO REFUND
Nothin adds excitment like something that is none of your business John is Near Kenwood TS-2000 housed in a 2005 Damon Intruder 377
Logthumper wrote: At least two companies manufacture a “Cheater Box”, which is sold thru several RV suppliers.
But I’m NOT looking for theories as to why they should not be used or why they are of a poor design.
THIS IS WHAT I'M LOOKING FOR:
I am looking for information from people with personal experience where a Cheater Box actually caused problems/damage to your RV or campground wiring?
The original question was: .....personal experience where a Cheater Box actually caused a problem........
I wonder how many of the nay-sayers have ever used a cheater box?
Most of the answers are knee-jerk responses as to why "THEY THINK" it won't work. As Imentioned before, it does work as advertized, it gives you the potential for 50 useable amps, half of what your 50 amp RV would like to have but 20 amps more than you would have without it. IF you don't have a GFI shorepower.
hershey - albuquerque, nm Someday Finally Got Here
My wife does all the driving - I just get to hold the steering wheel.
Expedition - Suzuki Grand Viagra
Offline
LOL
Online
 (Custom) (Custom) (Custom).JPG)
