RV News RVBusiness 2021 Top 10 RVs of the Year, plus 56 additional debuts and must-see units → ×
 

Go Back   Keystone RV Forums > Keystone Fleet | Keystone RV Models > Travel Trailers
Click Here to Login

Reply
 
Thread Tools Display Modes
 
Old 05-15-2019, 06:12 PM   #21
JRTJH
Site Team
 
JRTJH's Avatar
 
Join Date: Mar 2011
Location: Gaylord
Posts: 19,623
Quote:
Originally Posted by Logan X View Post
So if Iím understanding correctly, the trailerís circuit breakers will protect the trailer from an amperage overload, the EMS will protect from a voltage overload (and all of the other above mentioned problems). That makes sense.
You are correct. Plus, all the things that x-rated (Vern) listed are conditions and features of MOST EMS units. They all do "about the same thing" and now, Surge-Guard and PI offer "lifetime warranty" on their units, so they are "more alike than ever before".....
__________________

__________________
John



2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS
JRTJH is offline   Reply With Quote
Old 05-15-2019, 06:21 PM   #22
JRTJH
Site Team
 
JRTJH's Avatar
 
Join Date: Mar 2011
Location: Gaylord
Posts: 19,623
Quote:
Originally Posted by Snoking View Post
Biggest issue is plugging the device into a 50amp out outlet with a 30 trailer, as the shore cable and wiring from the trailers inlet to the trailer electrical panel is not protected correctly. We routinely plug in our 50amp TT with and 30 to 50 amp adapter. Just a few minutes ago DW started the microwave while the WH and portable heater were running and we are on a 30AMP outlet. The hardwired PI unit dumped the power based on low voltage.

I see no problem running an adapter on each side of the portable PI unit. The PI unit will still do it's job of looking for open grounds or neutrals, reverse polarity , low or over voltage, freguency etc.

PI units do not error or trip on amperage, that is left to the circuit breakers.
When you consider that the 25' 30 amp shore power cord is "rated 30 amps" at 50 feet, a 25' length of cord (the length most of us have) will carry somewhere between 34-40 amps for a short time without damage. The 30 amp power center in the trailer is "protected by a 30 amp circuit breaker. Theoretically (I haven't held the wire ends to verify this) if you plug the 30 amp shore power cord into a 50 amp outlet on the campground power pole, once you turn on enough "stuff" in the trailer to draw 30 amps, everything will work as designed. If you overload anything in the trailer and begin drawing 31 amps, the TRAILER main circuit breaker will trip, shutting down all power into the trailer (instantly eliminating ALL potential for overload. Since the shore power cord is rated at 30 amps at 50' long, it will carry more than that since it's only 25' long. Essentially, there's no way to damage the shore power cord or to overload it while attached to the trailer (as long as the trailer 30 amp breaker is functional)...

Of course, if you run over the shore power cord with a lawn mower, intentionally connect it to something drawing 50 amps (without circuit breaker protection) or somehow damage it, then all bets are off. However those are NOT "normal use" of the shore power cord, any adapter and the trailer main power center.

The rest of your post is "spot on" and as you said, the EMS will work as designed without problems.
__________________

__________________
John



2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS
JRTJH is offline   Reply With Quote
Old 05-16-2019, 05:36 AM   #23
Snoking
Senior Member
 
Snoking's Avatar
 
Join Date: Aug 2018
Location: Lake Stevens
Posts: 754
Circuit breakers are there for more than a single reason, along with electrical codes. Yes the 30 Amp main breaker in the power center will protect from overloads within the unit down stream of the panel. It will not protect one from a problem up stream of the power center that is supplied with wiring rated for 30amps and is feed from a 50amp supply.

In life beyound RVs this would be a code violation. Example would be a sub panel in your garage wired with #10 wire from a 50amp breaker in main panel. Red tag, failed inspection.

People just need to be aware of the risk no matter how small, as their lives could depend on it. Example could be a loose connection on a lead comimg in to the trailer at the inlet or panel that created enough heat to melt to insulation on the wires and allow a short to occur.
__________________
2019 Laredo 225MK for travel. Bighorn 3575el summer home in Washington, Park Model with Arizona Room for winters.
2015 RAM 3500 SRW CC SB Aisin Laramie
Snoking is offline   Reply With Quote
Old 05-23-2019, 08:50 AM   #24
trmanning
Junior Member
 
Join Date: Feb 2019
Location: Delaware
Posts: 4
Bad idea

Anytime you use a protector over the amperage itís protecting you run the risk of damage to the appliances. Then you have the chance of serious damage. A 30 amp surge protector protects up to 30 amps. Should you put a 15 amp fuse in a 10 amp circuit? I would never do so! Just hate to see it destroy their dreams.
trmanning is offline   Reply With Quote
Old 05-23-2019, 12:25 PM   #25
LHaven
Senior Member
 
LHaven's Avatar
 
Join Date: Feb 2019
Location: Wickenburg
Posts: 1,392
Quote:
Originally Posted by NH_Bulldog View Post
Think of it this way: If you have wiring in your house that will support a 15a load (14ga), and you connect that to a 20a breaker (intended for 12 ga wire), what will happen if you overload that 15a wiring? The breaker won't trip before the wires melt and will start a fire. In this case, unless you have a 30a breaker/surge protector, the wiring in the camper will be toast before it trips that 50a breaker/surge protector. Kind of defeats the purpose of a surge protector doesn't it?
A surge protector isn't a fuse or circuit breaker. Fuses and circuit breakers protect against over-current. Surge protectors protect against over-voltage. Whether you use a 30A or a 50A outlet, the voltage is still 120V between hot and neutral. An RV with a 30A adapter will be using only one of those legs. As long as the surge protector protects each of the legs independently, there's no reason you can't use it to protect a 30A RV.

(Though I do agree this is an awkward unit to manage when you're camping at a park with only 30A outlets.)
__________________
2019 Cougar 26RBSWE
2019 Ford F-250
LHaven is offline   Reply With Quote
Old 05-23-2019, 12:36 PM   #26
LHaven
Senior Member
 
LHaven's Avatar
 
Join Date: Feb 2019
Location: Wickenburg
Posts: 1,392
Quote:
Originally Posted by JRTJH View Post
if you plug the 30 amp shore power cord into a 50 amp outlet on the campground power pole, once you turn on enough "stuff" in the trailer to draw 30 amps, everything will work as designed.
Absolutely. 40 years ago, I had a power engineer explain it to me this way, and I've remembered this analogy ever since to keep my head straight on this issue:

The average lamp in your home has 14ga wire, which is rated only for 15A. You routinely plug them into house outlets that are rated and fused to supply 20A. This is NOT a violation of code or good practice, because the lamp is never going to draw more than some fraction of 15A. Yes, there is a fire danger if some adverse event physically shorts the lamp cord, but that's not considered a normal event. (Especially since it would have to be shorted in such a manner as to consume more than 15A but less than 20A, which is highly improbable.)
__________________
2019 Cougar 26RBSWE
2019 Ford F-250
LHaven is offline   Reply With Quote
Old 05-23-2019, 12:59 PM   #27
vmyoung61
Junior Member
 
Join Date: Jan 2015
Location: Davenport, FL
Posts: 18
Correct me if I'm wrong. Doesn't the 50 to 30 adapter just run the RV off one leg of the 50 service? So ... If you overload one leg, won't it trip? Besides - the Progressive is more than surge protection. You plug it in to make sure the pedistal is safe for the rv. It would still protect the 30 amp RV from bad wiring by showing an error.
__________________
Steve and Virginia Young
2014 Big Sky 382RL
2014 RAM 3500 4x4 Dually
vmyoung61 is offline   Reply With Quote
Old 05-23-2019, 02:50 PM   #28
bobbecky
Senior Member
 
bobbecky's Avatar
 
Join Date: Jul 2013
Location: Box Elder
Posts: 1,827
Most people, including most electricians, believe breakers and fuses protect connected loads. That is not the case. Breakers and fuses protect the system from a fault in the connected circuit, so the rest of the system doesn't fail due to an issue on the single circuit. Then, the main breaker in the RV panel does not protect the RV, but protects the main feed from a fault in the panel that exceeds whatever the main breaker is rated at. This continues all the way up stream, even to the utility sub station, with fuses and breakers protecting the source from failures and faults on the load sides. Yes, the fuse or breaker will open when a load exceeds the amp rating, but that is a potential fault that the device is protecting the rest of the system from.

If you have an RV with a 30 amp panel plugged into a 50 amp receptacle in a pedestal, the 30 amp breaker in the RV will open if the load or a fault occurs, to protect the source side of the RV panel. If the 30 amp shore cord fails due to a cut or some other damage, the 50 amp pedestal breaker will open up to protect the rest of the RV park from the shore cord failure. If something happens inside the pedestal, the breaker that feeds the string of pedestals inside the park's main panel will open up to protect the rest of the park, and so on up stream.
__________________
Bob & Becky
2012 3402 Montana
2012 Chevy 2500HD D/A CC
bobbecky is offline   Reply With Quote
Old 05-24-2019, 04:56 AM   #29
jimborokz
Senior Member
 
Join Date: Dec 2018
Location: Northville, NY
Posts: 249
Quote:
Originally Posted by John&Genny View Post
Some of you are comparing apples to oranges. A surge arrestor, or in this case a Electrical Management System is quite different than electrical breakers or fuses. A EMS monitors the line voltage looking for sags (brownouts) or overvoltage conditions. If it detects something that might be a problem, it will disconnect the power going to the TT. It also checks for improper wiring (disconnected grounds, reversed hot/neutral, etc.) and will not even apply power to the TT unless everything checks out OK. The Progressive 50A EMS is being plugged into a 50A connector at the pedestal, so no problem there. And I fail to see what the problem would be if they used a 50A to 30A dogbone going from the EMS to the TT. It would not be any different if they were plugging the dogbone into the pedestal directly. Certainly the 50A Progressive would handle any current or power requirements that a 30A TT would require.

Having said that, it would still probably be best if they took back the 50A and got a 30A Progressive instead. Not all sites have 50A service, but almost all sites have 30A. Also, itís better in the long run not to have too many electrical adapters in the chain if you can avoid it.
I believe this is spot on. Basically the EMS is monitoring the post which in this case is 50A. The idea that you could overload the 30A camper and not trip the 50A breaker at the post has nothing to do with the EMS. You would still not trip that breaker even without the EMS. You should at that point be tripping the 30A main in the camper.
jimborokz is offline   Reply With Quote
Old 05-24-2019, 06:30 AM   #30
gearhead
Senior Member
 
Join Date: Jul 2013
Location: Liberty, Texas
Posts: 3,464
I run a portable Progressive 50 amp on my 30 amp Bigfoot all the time. Just use a dogbone between the camper wire and the Progressive. I have a 30 to 50 dogbone for 30 only pedestals but don't recall if I ever used it.
I have a 30amp SurgeGuard but don't trust it.
__________________
2018 Ram 3500 Laramie CC DRW LWB 4X4 Cummins Aisin 3.73
Pullrite Superlite 2600
2018 Heartland Landmark 365 Oshkosh
2008 Bigfoot 25C9.4 LB Cabover
gearhead is offline   Reply With Quote
Old 05-25-2019, 03:39 PM   #31
kksfish
Senior Member
 
Join Date: Aug 2016
Location: Rincon
Posts: 191
For all the reasons John and Vern mention........The 50 Amp surge protector and assorted dog ones are what I have used for years and will continue to use! With the 50 I am protected in just about any configuration imaginable!
I have attended a number of seminars conducted by the major manufacturers of over current devices and I instructed 4th year apprenticeship programs and as such have experimented with many OC/grounding scenarios and I am very comfortable with this.....
__________________

__________________
2017 Ram 3500 CC Cummins
2011 Keystone Laredo 266 RL
kksfish is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by the Keystone RV Company or any of its affiliates in any way. Keystone RVģ is a registered trademark of the Keystone RV Company.


All times are GMT -8. The time now is 06:03 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×