30 Amp vs 50 Amp

[DJ Cruz]

Hello Campers,

I have a 2018 Cougar 29BHSWE. It can run on 30 Amps fine. However I was warned that I may draw too much amperage to run the microwave and the heater/ac at the same time. (I've operated both at the same time on a 30 amp and all was well; like no fuses blown)

My question is, can I use a 50 amp camp site and be ok? Or is it just a waste of money to spend the extra dollars for a 50 amp when I just need a 30 amp?

Thanks!

[DocP]

You're still only going to get 30 amps at a 50 amp site, and will need an adapter to take you from 50 amps at the campground pedestal down to 30 amps at your trailer.

[JRTJH]

Your trailer has a "main circuit breaker" located in the power distribution panel that is rated at 30 amps. That breaker will not allow more than 30 amps to flow through the power cable and into the trailer distribution panel. It doesn't matter whether you're attached to a 30 amp campground pedestal, a 50 amp campground pedestal or a 100 amp campground pedestal, the maximum power that can pass through that circuit breaker is 30 amps. Typically, the air conditioner uses about 12 amps and the microwave about 10 amps. That's 22 amps with both running. When the A/C starts, it uses about 18 amps which would "push the use" to the maximum available in the power center. Usually there are "hidden users" of power that aren't typically considered. The refrigerator uses about 1.5 amps, the converter (supplies all 12 VDC power) uses about 5-8 amps, the water heater uses about 10 amps. Any 120VAC appliances like a hair dryer, coffee pot, toaster, small heater, etc would also add to that power consumption.

It really makes no difference which power plug you connect to at the campground pedestal as long as it's rated at/greater than 30 amps. What does make a difference is how many other campers are on that leg of power, how much they are reducing the available power (brownout) and whether you have a "true 30 amps" available on that leg of the campground distribution. Usually there are fewer trailers connected to the 50 amp system and those plugs are in better physical condition (not as worn with loose connectors in the plugs) so it often is "advantageous" to use the 50 amp power plug.

I'd question whether you should pay for (or be charged for) using the 50 amp plug with a 30 amp trailer. you can argue the point that the maximum you could possibly draw is 30 amps, no matter which plug you use, so effectively you can never "use 50 amp service" with a trailer rated at 30 amps.

That said, if you start plugging in additional extension cords, that's more than 30 amps, but that's not typically what happens......

[flybouy]

Your breaker in the inside panel has a 30 amp main breaker so that limits it. IF, and it's a big IF the cg is providing 120 volts than you have the full 30 amps to use. If the voltage drops, then the amperage draw will rise (Ohm's Law) and your devises will draw higher amps. My camper has the 15K roof top unit and I can get away with the microwave and the ac on IF the cg is providing 120 volts but then again I have an Autoformer - https://hughesautoformers.com/ to help out with high demand.

[sourdough]

As has been explained, it would be pointless to pay for a 50 amp site - you cannot pull more than 30A. Now if you opt for a 50A site you will probably pay more if those sites are limited. Many parks only have a certain number of 50A sites and those are more regardless of what you plug into them, some have 15, 30 and 50A in all pads and some have no 50A at all. Just go with the 30A and use what you can depending on the site's ability to deliver power.....make sure you have an EMS/surge protector.

[xrated]

According to the info that I'm finding on the Cougar 29BHSWE that unit comes with a 50 service, not a 30. DJ....if you can look at the cord that came with the trailer and let us know if there are three prongs on the end of the cord or if there are four prongs on the end of it. I'm thinking you have a 50A service as per the manufacturer's information that I've seen. Let us know.

[Hodgy]

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So I watched the video about the Autoformer, no explanation of how it works. Smoke and mirrors ?

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[travelin texans]

You could get the surge protector/EMS for 1/2 of the price of the Auto Former. Which you choose is up to you, the main thing is some sort of protection is absolutely necessary, I won't it in without it.

[JRTJH]

According to the info that I'm finding on the Cougar 29BHSWE that unit comes with a 50 service, not a 30. ...

The 2018 29BHSWE is a travel trailer and according to the "options list" at the bottom of the page, that trailer comes standard with 30 amp service and 50 amp service is optional.... It's the 12th item in the options list at the bottom of the page: http://www.keystonerv.com/cougar-half-ton/

[DJ Cruz]

Thank you EVERYONE here for your input and knowledge. I appreciate the responses and I'm glad we can contribute to a better camping experience.

We reserved a spot at a KOA which supplies a 30 amp service.

[flybouy]

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So I watched the video about the Autoformer, no explanation of how it works. Smoke and mirrors ?

.

It's basically a capacitor bank with electronics to engage it. The people that run very high amperage car audio amplifiers use large capacitors to compensate for high amplifier demands. Motors, like the compressor in the air conditioner use them in the start wiring circuit to offset the high current in rush during start up to correct the power factor.

[Hodgy]

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Thanks for explaining.

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[Tinner12002]

Well the OP never did say if he had a 30 or 50amp RV so at this point its all speculation. Is he trying to save money by wanting to use a 30 instead of 50 if his rv is setup to use that or is his rv set to run on 30 amp??

[Dave W]

This is what works for me:D

The easiest 'rule of thumb' to me is watts in a service and how I explained it to my non technical DW

30 amps = 3600 watts @120VAC (36 100 watt bulbs)
50 amps per leg is 12,000 watts(120 100 watt bulbs)

Since I carry both 30 and 50 amp cords and adapters make my decision on expected outside temperatures and whether I need both air conditioners. I also factor in length of stay when traveling. Overnight, normally the much easier to handle 30 amp cords, And the DW, she has been 'trained' to not operate too many ' hogs' at the same time.

What 'they' don't tell you is that a 50 amp RV service is really 100 amps and that each leg or conductor is capable of carrying 50 amps.

Easy formulas
20x120 = 2400 watts
30x120 - 3600 watts
50x2x120 = 12000 watts

If the voltage varies, so will the wattage. If a CG system is less or more, then your wattage will change accordingly

[xrated]

It's basically a capacitor bank with electronics to engage it. The people that run very high amperage car audio amplifiers use large capacitors to compensate for high amplifier demands. Motors, like the compressor in the air conditioner use them in the start wiring circuit to offset the high current in rush during start up to correct the power factor.

You are mistaken about it being a capacitor bank. Here is a link to do some reading about autoformers if you are interested.....

https://www.google.com/search?source=hp&ei=Y0tnWu6iC4WwtQXJ07pg&sjs=1&q=how+does+an+auto+transformer+work&oq=how+does+an+auto+transformer+work&gs_l=mobile-gws-hp.3...4535.20350.0.22253.0.0.0.0.0.0.0.0..0.0.... 0...1.1j4.64.mobile-gws-hp..0.0.0....0.4TxK-b8jX54

[Gail2568]

Something else to note between the 30 and 50.

Thirty amp is strictly 120VAC, hot, neutral, and ground.
Fifty amp is 120/220VAC, hence the four wire plug. you have TWO hot wires, a neutral, and a ground.

Had a friend get his trailer fried because the local handy man transferred the wires from the fifty to the thirty because the thirty was having problems and he didn't know what he was doing. Instead of grabbing the hot, neutral, and ground, the idiot grabbed the two hots and a ground pumping 220 into the 110 trailer system. Can we say smoke signals anyone?

[Tinner12002]

I'll just use my 50amp cord with my 50amp RV and be happy! Lol!

[travelin texans]

In all our years fulltiming there have only been a couple parks that charged more for 50 amp, some have different areas with 50 amp, on occasion we've had to stay a parks with only 30 amp, but most all parks we've been to have had both at the pedestal & whether I need 2 acs, or none, I'm plugging into 50 amp every time & will pay the couple bucks difference if need be.
Anyone reading this thread that doesn't have a surge protector/EMS ,GET ONE before plugging in your next outing. With all the electronics nowadays it's mandatory to protect it. Yes the protection is expensive, but so is replacing acs, fridges, multiple tvs.

[bobbecky]

Something else to note between the 30 and 50.

Thirty amp is strictly 120VAC, hot, neutral, and ground.
Fifty amp is 120/220VAC, hence the four wire plug. you have TWO hot wires, a neutral, and a ground.

Had a friend get his trailer fried because the local handy man transferred the wires from the fifty to the thirty because the thirty was having problems and he didn't know what he was doing. Instead of grabbing the hot, neutral, and ground, the idiot grabbed the two hots and a ground pumping 220 into the 110 trailer system. Can we say smoke signals anyone?

Be cautious about looking for 220, (actually the proper voltage would be 240 volts), because there are a few parks out there that you will see 208 volts across the two hot legs, instead of 240 volts, because the transformer supplying power is a wye connected transformer instead of a delta connected transformer. You need to only verify that you have 120 volts to ground or neutral from each hotleg. This is the label at the shore cable connector on our rig.

[Dave W]

Be cautious about looking for 220, (actually the proper voltage would be 240 volts), because there are a few parks out there that you will see 208 volts across the two hot legs, instead of 240 volts, because the transformer supplying power is a wye connected transformer instead of a delta connected transformer. You need to only verify that you have 120 volts to ground or neutral from each hotleg. This is the label at the shore cable connector on our rig.


In that case, the surge protector would say No Way.

Interesting as I have never seen any power service warning label beyond personal safety at any campground

[xrated]

In that case, the surge protector would say No Way.

Interesting as I have never seen any power service warning label beyond personal safety at any campground

I'm not sure that it would say..."No Way". If I'm not mistaken, the surge protectors are looking for 120VAC on each of the hot legs with respect to the neutral. So as long as you have 120V - N on one leg, then 120V - N on the other leg, life will be good. I don't think it monitors for the voltage phase to phase.

[Javi]

I'm not sure that it would say..."No Way". If I'm not mistaken, the surge protectors are looking for 120VAC on each of the hot legs with respect to the neutral. So as long as you have 120V - N on one leg, then 120V - N on the other leg, life will be good. I don't think it monitors for the voltage phase to phase.

Product Features:

Over/Under voltage Protection
Open Ground, Open Neutral & Reverse Polarity Detection
Open Ground, Open Neutral & Reverse Polarity Protection
Accidental 240V Protection
Miswired Pedestal Indication
Surge Failure Indicator
Amperage Meter Display
Previous Error Code
A/C Frequency Protection
Time Delay (136 seconds)
Adjustable Time Delay
Thermally Protected
Built-in Scrolling Digital Display
Remote Display
Field Serviceable
UL Certified and Canadian Approved
Lifetime Warranty
Made in the USA
​
Product Specs:
Surge Protection: 5-Mode / 3,580J / 88,000A
Ratings: 50A / 120V/240V / 12,000W
Operating Temperatures: -40C to +105C

[Dave W]

I think the surge protector would show as one leg under voltage on the digital readout and not energize at all. In that case, out come the 30 amp cords

[xrated]

I think the surge protector would show as one leg under voltage on the digital readout and not energize at all. In that case, out come the 30 amp cords

I'm curious why you would think that one leg would show undervoltage? Both legs, with respect to neutral would be 120VAC!

I'm thinking that it would work as it was made to do, as each leg is monitored separately as an input to the unit. I've sent an email to their tech support, so hopefully I'll have an answer soon and I will post up the answer here....that way we will all know for sure.

[shiggs68]

I'm curious why you would think that one leg would show undervoltage? Both legs, with respect to neutral would be 120VAC!

I'm thinking that it would work as it was made to do, as each leg is monitored separately as an input to the unit. I've sent an email to their tech support, so hopefully I'll have an answer soon and I will post up the answer here....that way we will all know for sure.



https://uploads.tapatalk-cdn.com/20180128/0540e1f7f790914cd319b30ecfb15c36.jpg
Notice the attach specifications for the Progressive Industries Surge Protectors with EMS, both 30 and 50amp modules monitor for 104 to 132vac range. Any voltage outside this range will shutdown the connection.

On a side note, if your RV has a Energy Management System, the 50amp shore power is monitored for 240vac hot to hot. If not present, the system assumes you are using a 30amp adapter and shreds various loads to keep you under the 30amp limit.

Also the 120/240 volt availability is the result of a center tapped transformer, not a 3-phase delta connection. It’s sometimes called split-phase. Same as the service provided to your sticks and bricks home.



Sent from my iPad using Tapatalk

[Hodgy]

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What are the brand names and model numbers of the surge protectors you guys are talking about ?

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[xrated]

https://uploads.tapatalk-cdn.com/20180128/0540e1f7f790914cd319b30ecfb15c36.jpg
Notice the attach specifications for the Progressive Industries Surge Protectors with EMS, both 30 and 50amp modules monitor for 104 to 132vac range. Any voltage outside this range will shutdown the connection.

On a side note, if your RV has a Energy Management System, the 50amp shore power is monitored for 240vac hot to hot. If not present, the system assumes you are using a 30amp adapter and shreds various loads to keep you under the 30amp limit.

Also the 120/240 volt availability is the result of a center tapped transformer, not a 3-phase delta connection. It’s sometimes called split-phase. Same as the service provided to your sticks and bricks home.



Sent from my iPad using Tapatalk

Do you know for sure..100% that it is monitored for 240V? I was thinking that it monitored each individual hot leg, with respect to neutral. And also the question that I am wondering is that when they designed the system, did they build in the monitoring voltage to include a 208 wye connected system....and thus allow for the sensor to accept the 208 volt in addition to the normal 240V that it would see with a center-tapped single phase transformer.

I don't think I ever mentioned the words...."3-Phase Delta connection". But if the park is using a 3 phase wye type setup, then the first pedestal would most likely have phase A and phase B and a neutral. The second pedestal would have phase B and phase C and a neutral, then the third pedestal would have phase A and phase C and a neutral......then repeat for pedestals 4, 5, and 6.....and so on.

And the part above that you have circled in red, proves nothing, other than what the system monitors as far as 120 volts. As long as your voltage is within those parameters, it doesn't care if the voltage is coming from a single phase center-tapped transformer that you would traditionally see at your house, or if it is two of the three phases from a 3 phase wye connection......the monitoring points inside the EMS is looking for the 120 volts on both of the legs....or should I say, that the voltage is within the parameters that is set ...104 - 132 volts. It doesn't say anywhere that I can find that it is monitoring for 240Volts.

[xrated]

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What are the brand names and model numbers of the surge protectors you guys are talking about ?

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Progressive Industries......EMS-HW50C. They make models for 30A and for 50A and they also make those same units with and without the display. In addition to those, they also make portable units for both 30A and 50A. Here is a link to their product page.....

http://www.progressiveindustries.net/our-products

[Javi]

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What are the brand names and model numbers of the surge protectors you guys are talking about ?

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This is what I run... won't own an RV without one... http://www.progressiveindustries.net/ems-hw50c

[Hodgy]

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Thanks for the link.

Quite a difference in price between the plug in and hardwire.

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[Javi]

Do you know for sure..100% that it is monitored for 240V? I was thinking that it monitored each individual hot leg, with respect to neutral. And also the question that I am wondering is that when they designed the system, did they build in the monitoring voltage to include a 208 wye connected system....and thus allow for the sensor to accept the 208 volt in addition to the normal 240V that it would see with a center-tapped single phase transformer.

I don't think I ever mentioned the words...."3-Phase Delta connection". But if the park is using a 3 phase wye type setup, then the first pedestal would most likely have phase A and phase B and a neutral. The second pedestal would have phase B and phase C and a neutral, then the third pedestal would have phase A and phase C and a neutral......then repeat for pedestals 4, 5, and 6.....and so on.

And the part above that you have circled in red, proves nothing, other than what the system monitors as far as 120 volts. As long as your voltage is within those parameters, it doesn't care if the voltage is coming from a single phase center-tapped transformer that you would traditionally see at your house, or if it is two of the three phases from a 3 phase wye connection......the monitoring points inside the EMS is looking for the 120 volts on both of the legs....or should I say, that the voltage is within the parameters that is set ...104 - 132 volts. It doesn't say anywhere that I can find that it is monitoring for 240Volts.

Go back and look at my earlier post... it says Accidental 240V Protection

[travelin texans]

.

Thanks for the link.

Quite a difference in price between the plug in and hardwire.

.

It all depends on your situation. If you plan to keep the rv for a long time, yes the hardwired is cheaper, but if trading in a couple years you'll have to pay for another hardwired one. I've used my portable for the last 10 years on 3 different rvs, so in my situation the portable was a lot cheaper than buying 3 hardwired ones.

[Hodgy]

It all depends on your situation. If you plan to keep the rv for a long time, yes the hardwired is cheaper, but if trading in a couple years you'll have to pay for another hardwired one. I've used my portable for the last 10 years on 3 different rvs, so in my situation the portable was a lot cheaper than buying 3 hardwired ones.


The prices I looked at the hardwired was twice the price of the plug in.

I can't see us getting another TT.


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[shiggs68]

Do you know for sure..100% that it is monitored for 240V? I was thinking that it monitored each individual hot leg, with respect to neutral. And also the question that I am wondering is that when they designed the system, did they build in the monitoring voltage to include a 208 wye connected system....and thus allow for the sensor to accept the 208 volt in addition to the normal 240V that it would see with a center-tapped single phase transformer.

I don't think I ever mentioned the words...."3-Phase Delta connection". But if the park is using a 3 phase wye type setup, then the first pedestal would most likely have phase A and phase B and a neutral. The second pedestal would have phase B and phase C and a neutral, then the third pedestal would have phase A and phase C and a neutral......then repeat for pedestals 4, 5, and 6.....and so on.

And the part above that you have circled in red, proves nothing, other than what the system monitors as far as 120 volts. As long as your voltage is within those parameters, it doesn't care if the voltage is coming from a single phase center-tapped transformer that you would traditionally see at your house, or if it is two of the three phases from a 3 phase wye connection......the monitoring points inside the EMS is looking for the 120 volts on both of the legs....or should I say, that the voltage is within the parameters that is set ...104 - 132 volts. It doesn't say anywhere that I can find that it is monitoring for 240Volts.



The PI EMS monitors each line for voltage within the stated ranges and does not care about it being a true 50amp split phase system. That allows the 50amp model to work when using a 30 to 50 adapter.

You didn’t mention the “3-phase delta”. However, it was mentioned above by Gail2536.

And my comment on the monitoring for 240vac is for systems like the Precision Controls Energy Management System used in numerous Motorhomes and higher-end 5th wheels. That is the method to detect that a 30 to 50 adapter is being used. I mention this as their are campgrounds that cheat and provide the same phase to each leg. Which causes the user’s system to think its connected to a 30amp source.

Sorry for the confusion.


Sent from my iPad using Tapatalk

[Javi]

The prices I looked at the hardwired was twice the price of the plug in.

I can't see us getting another TT.


.

I installed mine in about an hour and 3 feet of cable... So removing it would probably take even less time..

As a note... I was looking at a new 5th wheel (375RD Avalanche) yesterday and the sales fellow asked me what I needed to buy it... I told him I didn't need nothing but that trailer needs a Progressive EMS, slide awnings, the washer dryer connections plugged and Maxxair vent fans in every vent with covers...

[xrated]

Go back and look at my earlier post... it says Accidental 240V Protection

In my mind, that would basically mean that it is looking for an open neutral, which would then cause it to see the 240volts on the two line leads...vs. the 120 to neutral that it should be seeing.

The other "possibility" that might trigger the 240V protection is that if, when plugged in at a pedestal, one of the line leads and the neutral wire were swapped. That would generate and "E1" error code.

So, I still stand by my question....will the 208 wye connected supply voltage allow the unit to work as it should. I did email tech support at Progressive, but have not heard back from them yet.....it is the weekend and I really didn't prioritize it as something that needs attention NOW...so maybe tomorrow or Tuesday.

[Javi]

In my mind, that would basically mean that it is looking for an open neutral, which would then cause it to see the 240volts on the two line leads...vs. the 120 to neutral that it should be seeing.

The other "possibility" that might trigger the 240V protection is that if, when plugged in at a pedestal, one of the line leads and the neutral wire were swapped. That would generate and "E1" error code.

So, I still stand by my question....will the 208 wye connected supply voltage allow the unit to work as it should. I did email tech support at Progressive, but have not heard back from them yet.....it is the weekend and I really didn't prioritize it as something that needs attention NOW...so maybe tomorrow or Tuesday.Generally I've gotten an answer from them within a day.

Javi

[bobbecky]

In my mind, that would basically mean that it is looking for an open neutral, which would then cause it to see the 240volts on the two line leads...vs. the 120 to neutral that it should be seeing.

The other "possibility" that might trigger the 240V protection is that if, when plugged in at a pedestal, one of the line leads and the neutral wire were swapped. That would generate and "E1" error code.

So, I still stand by my question....will the 208 wye connected supply voltage allow the unit to work as it should. I did email tech support at Progressive, but have not heard back from them yet.....it is the weekend and I really didn't prioritize it as something that needs attention NOW...so maybe tomorrow or Tuesday.

The Progressive unit, and we have the 50 amp hardwired one, does not monitor phase to phase voltage, only phase to ground and phase to neutral. It will work with either a 50 amp four wire source or a 30 amp three wire source equally well. It doesn't care how you get your 120 volt legs, whether they are two different legs like a normal 50 amp source or the same 120 volt leg, normally what you would have hooked up to a 30 amp source and with a 30 amp to 50 amp dogbone adapter. Because it doesn't look at the phase to phase voltage, it doesn't see 240 volts, 208 volts, or in the case of a 30 amp source split to feed both hotlegs of a 50 amp trailer, it would see 0 volts, because there is no voltage difference between two like legs. The accidental 240 volts it monitors is when an outlet, whether it is a 30 amp or a 50 amp, has a hot leg and neutral or ground in the wrong place, or as we have seen before when an electrician wires a 30 amp outlet like a dryer outlet with two hotlegs instead of just one 30 amp leg and everything in the rig burns up from 240 volt instead of 120 volts. If you look at the Error Code Chart in the Progressive manual, none of the error codes say anything about phase to phase voltages, only Line 1 Low or High Voltage or Line 2 Low or High Voltage. Hopefully, this answers any questions about what voltages are acceptable in these rigs. And, the photo that I posted earlier in this thread of the label that talks about 208 or 240 volts is what Keystone applied to our trailer below the shore cable connector where the 50 amp shore cable plugs into, and we have been in parks with 208 volts and everything worked as it was supposed to.

[Hodgy]

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So do some CG 30 amp plugs have two hot legs ?

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[chuckster57]

.

So do some CG 30 amp plugs have two hot legs ?

.



Better not! 3 wires:

Hot
Neutral
Ground

[Hodgy]

Better not! 3 wires:

Hot
Neutral
Ground


I know that is what it is supposed to look like. I thought I saw in one post that some CG's had hinky wiring.

.

[chuckster57]

That’s why I have a surge protector. Mine is hard wired, and with remote display, I can monitor my power while comfortably inside.

[xrated]

The Progressive unit, and we have the 50 amp hardwired one, does not monitor phase to phase voltage, only phase to ground and phase to neutral. It will work with either a 50 amp four wire source or a 30 amp three wire source equally well. It doesn't care how you get your 120 volt legs, whether they are two different legs like a normal 50 amp source or the same 120 volt leg, normally what you would have hooked up to a 30 amp source and with a 30 amp to 50 amp dogbone adapter. Because it doesn't look at the phase to phase voltage, it doesn't see 240 volts, 208 volts, or in the case of a 30 amp source split to feed both hotlegs of a 50 amp trailer, it would see 0 volts, because there is no voltage difference between two like legs. The accidental 240 volts it monitors is when an outlet, whether it is a 30 amp or a 50 amp, has a hot leg and neutral or ground in the wrong place, or as we have seen before when an electrician wires a 30 amp outlet like a dryer outlet with two hotlegs instead of just one 30 amp leg and everything in the rig burns up from 240 volt instead of 120 volts. If you look at the Error Code Chart in the Progressive manual, none of the error codes say anything about phase to phase voltages, only Line 1 Low or High Voltage or Line 2 Low or High Voltage. Hopefully, this answers any questions about what voltages are acceptable in these rigs. And, the photo that I posted earlier in this thread of the label that talks about 208 or 240 volts is what Keystone applied to our trailer below the shore cable connector where the 50 amp shore cable plugs into, and we have been in parks with 208 volts and everything worked as it was supposed to.

Thank you for that explanation and confirmation of what I had stated earlier that I believed. Hopefully, that should clear it up for everyone....myself included. :D

[xrated]

The Progressive unit, and we have the 50 amp hardwired one, does not monitor phase to phase voltage, only phase to ground and phase to neutral. It will work with either a 50 amp four wire source or a 30 amp three wire source equally well. It doesn't care how you get your 120 volt legs, whether they are two different legs like a normal 50 amp source or the same 120 volt leg, normally what you would have hooked up to a 30 amp source and with a 30 amp to 50 amp dogbone adapter. Because it doesn't look at the phase to phase voltage, it doesn't see 240 volts, 208 volts, or in the case of a 30 amp source split to feed both hotlegs of a 50 amp trailer, it would see 0 volts, because there is no voltage difference between two like legs. The accidental 240 volts it monitors is when an outlet, whether it is a 30 amp or a 50 amp, has a hot leg and neutral or ground in the wrong place, or as we have seen before when an electrician wires a 30 amp outlet like a dryer outlet with two hotlegs instead of just one 30 amp leg and everything in the rig burns up from 240 volt instead of 120 volts. If you look at the Error Code Chart in the Progressive manual, none of the error codes say anything about phase to phase voltages, only Line 1 Low or High Voltage or Line 2 Low or High Voltage. Hopefully, this answers any questions about what voltages are acceptable in these rigs. And, the photo that I posted earlier in this thread of the label that talks about 208 or 240 volts is what Keystone applied to our trailer below the shore cable connector where the 50 amp shore cable plugs into, and we have been in parks with 208 volts and everything worked as it was supposed to.

Update...... This was confirmed by a tech. at progressive Industries for me today. So the bottom line is that if you happen into an RV park that is using a 3 phase, 208V Wye connected transformer to feed the pedestals, and is hooked up correctly, your P.I. brand 50 amp E.M.S. system WILL operate correctly and offer full protection of your trailer. That type of system provides 120 volts between a hot and neutral. It would be wired so that there are 2 of the 3 hot legs coming to the receptacle that you plug your camper into ( just like a single phase center-tapped transformer like at your house) and of course the neutral and ground being there too.