Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 
 


Reply
 
Thread Tools Display Modes
 
Old 04-20-2018, 12:23 PM   #41
Platinum Member
 
markopolo's Avatar
 
Join Date: Oct 2006
Location: New Brunswick, Canada
Posts: 8,828
Default

Just another general observation.

Some campsites only have a 50A receptacle at the pedestal. I spent 4 months on such a site once. Their website advises you to bring a 50A to 30A adapter if needed as they only have a limited supply of adapters to loan. I once chose to use the 50A receptacle at another campground because the 30A receptacle was melted.

I mention this to point out that some form of breaker or interrupt would be needed at the first incoming electrical point of contact to make sure that the shore power cord never sees more than 30A (assuming your rig only has a 30A rated cord).

In more RV traditional setups that 30A interrupt would occur at the RV main panel 30A breaker if the rig was plugged into a 50A receptacle.

I have a Samlex inverter/charger unit that lets the user set the incoming amp limit / protection. I can set it to 12A if using a 12A rated cord for example. I normally have it set at 30A so plugging into a 50A receptacle is not concern. The cord won't see more than 30A for more than 5 seconds.

It appears to me that there could be the potential for overloading the 30A rated shore power cord on the unit being discussed in this topic if connected to 50A shore power and if the charger is running at max output at the same time that heavy current usage is occurring at the downstream RV house panel. The instruction manual referred to in this topic (installation point 8 says to use a 40A breaker to allow for charger consumption in addition to allowing full use of the 30A pass through. That seems to tell you that the shore power cord could be exposed to greater than 30A with nothing to interrupt it other than the campsite power pedestal breaker as incoming power appears to be split at the terminal block to allow powering the charger.

Maybe someone who owns one of those units could confirm if this is correct.
markopolo is offline   Reply With Quote
Old 04-20-2018, 01:40 PM   #42
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 11,917
Default

Marko's scenario can happen for sure. This is a possibility that has always existed, but the direct wiring of the inverters to shore power has made it worse in some cases. AFAIK, most of the RVs have been wired directly into the van from the post through the power cord, many times to a transfer switch and no often through a power conditioner before going to the breaker panel where the first 30 amp breaker is. At minimum you have a 30 amp cord that is subject to 50 possible amps and more likely also have one or two unprotected devices also the same way. Personally, I have never cared for the whole idea of the 50 to 30 adapters for this reason, and I don't understand why a built in breaker or fuse isn't required in them.

In the melted wires scenario, I am having trouble figuring how you could melt the input hot and output neutral from a pure overload condition or a short to chassis. The explanation says the power could go to the van chassis and then back down the output neutral to inverter, but the latest diagram only show a ground buss to box connection, no neutral to box bond.

Normally, if you had a neutral to ground bond at the inverter, which may be happening, and it shorts to chassis, and if you have more amps available than the wire can handle, you would overheat the input hot wire, but the ground and neutral would share load back to the power pole so might survive. I can't see how you would get power coming back on the output neutral unless you had isolated neutral and ground at the inverter and a bond somewhere else on the output side, but even then you would be sharing the ground and neutral from the box back to inverter unless the ground was also open. Looking at the heat damage to the connector, it looks a lot more like there were two loose connections that got hot with the unit in pass though shore power. If it were truly shorted and had more than 30 amps available there would be some other heat related things visible on the other wires, which look normal in the pic. At minimum I would think you would see heat damage at the other end of the output neutral, the input neutral,or at the power plug (which is often the hottest running connection in the system).
booster is offline   Reply With Quote
Old 04-20-2018, 01:59 PM   #43
Platinum Member
 
Join Date: Mar 2018
Location: California
Posts: 132
Default

Quote:
Originally Posted by markopolo View Post
This link might help you understand how it got an ETL Listed Mark: https://ramuk.intertekconnect.com/We...c?OpenDocument


Attachment 5585
Yes, that's the same as UL. Thereafter UL monitors the factory and bill of materials with periodic inspections. Intertek's VP told me they do the same thing. They are investigating but will not report back except to say the investigatation is completed. How many people have new and dangerous inverters?
ContinuousImprovement is offline   Reply With Quote
Old 04-20-2018, 02:13 PM   #44
Platinum Member
 
Join Date: Mar 2018
Location: California
Posts: 132
Default

Quote:
Originally Posted by booster View Post
Marko's scenario can happen for sure. This is a possibility that has always existed, but the direct wiring of the inverters to shore power has made it worse in some cases. AFAIK, most of the RVs have been wired directly into the van from the post through the power cord, many times to a transfer switch and no often through a power conditioner before going to the breaker panel where the first 30 amp breaker is. At minimum you have a 30 amp cord that is subject to 50 possible amps and more likely also have one or two unprotected devices also the same way. Personally, I have never cared for the whole idea of the 50 to 30 adapters for this reason, and I don't understand why a built in breaker or fuse isn't required in them.

In the melted wires scenario, I am having trouble figuring how you could melt the input hot and output neutral from a pure overload condition or a short to chassis. The explanation says the power could go to the van chassis and then back down the output neutral to inverter, but the latest diagram only show a ground buss to box connection, no neutral to box bond.

Normally, if you had a neutral to ground bond at the inverter, which may be happening, and it shorts to chassis, and if you have more amps available than the wire can handle, you would overheat the input hot wire, but the ground and neutral would share load back to the power pole so might survive. I can't see how you would get power coming back on the output neutral unless you had isolated neutral and ground at the inverter and a bond somewhere else on the output side, but even then you would be sharing the ground and neutral from the box back to inverter unless the ground was also open. Looking at the heat damage to the connector, it looks a lot more like there were two loose connections that got hot with the unit in pass though shore power. If it were truly shorted and had more than 30 amps available there would be some other heat related things visible on the other wires, which look normal in the pic. At minimum I would think you would see heat damage at the other end of the output neutral, the input neutral,or at the power plug (which is often the hottest running connection in the system).
Hi Booster,. You're a great detective. I got to the bottom of this incident. The inverter had two problems, both with the same cause: incorrectly terminated wires. The fourth from the right white neutal wire was the cause of the final failure. The stranded wire loosen from the connector, resistance went up, got hot and finally failed. The second from the right black wire would have done the same thing soon. That is the shore power line and the connector is golden brown from getting hot in the past.

All six stranded wires should have been crimped terminated to a pin and then the pin is clamped in the new inverter's set screw connector. https://www.walmart.com/ip/12-10-Ga-Insulated-Pin-Terminals-pack-of-50/101997270?wmlspartner=wlpa&selectedSellerId=488&ad id=22222222228109387881&wl0=&wl1=g&wl2=m&wl3=23372 3746241&wl4=pla-386007741553&wl5=9031611&wl6=&wl7=&wl8=&wl9=pla&wl 10=111830364&wl11=online&wl12=101997270&wl13=&veh= sem

This inverter's return line had an open. Our safety campaign is over shorts. This case was two steps from hazardous or fatal shock. The promaster chassis would be live 115 volts had the broken return wire fallen, laid on the chassis and the Aktiv was plugged into 30 amp shore power.
ContinuousImprovement is offline   Reply With Quote
Old 04-20-2018, 02:19 PM   #45
Site Team
 
avanti's Avatar
 
Join Date: Jul 2013
Posts: 5,321
Default

BlueSea makes this very nice and inexpensive little breaker box, intended to be the first thing on your boat after the shore-power cord:

control panel 2.JPG

It doesn't rigorously protect the 30A cord the way a breaker on the other end would, but it is pretty good.

I installed one along with a Leviton residential surge suppressor at my shore input:

control panel 1.JPG
__________________
Now: 2022 Fully-custom buildout (Ford Transit EcoBoost AWD)
Formerly: 2005 Airstream Interstate (Sprinter 2500 T1N)
2014 Great West Vans Legend SE (Sprinter 3500 NCV3 I4)
avanti is online now   Reply With Quote
Old 04-20-2018, 02:32 PM   #46
Platinum Member
 
Join Date: Mar 2018
Location: California
Posts: 132
Default

Quote:
Originally Posted by avanti View Post
BlueSea makes this very nice and inexpensive little breaker box, intended to be the first thing on your boat after the shore-power cord:

Attachment 5587

It doesn't rigorously protect the 30A cord the way a breaker on the other end would, but it is pretty good.

I installed one along with a Leviton residential surge suppressor at my shore input:

Attachment 5586
Nice, thanks. I'll do that to. Has anyone ever found GFCI to install at the same location? It needs to have lower sensitivity to stop nuisance trips.
ContinuousImprovement is offline   Reply With Quote
Old 04-20-2018, 02:49 PM   #47
Platinum Member
 
GeorgeRa's Avatar
 
Join Date: Feb 2016
Location: Portland, Oregon
Posts: 3,141
Default

I have the same 30A BlueSea breaker as shown on Pete’s post but incorporated into the panel. Practically all my wires are marine type with crimp terminals and shrink tubing. Del City is a great place to get quality connectors https://www.delcity.net/store/Terminals/.

My van has 2 inverters. A 1000W Magnum with built in ATS and all outputs are GFCI. The small and very efficient (no fan) 300W Mornigstar is fully independent with 2 separate GFCI outlets and it is bonded in situ.
Attached Images
File Type: jpg ZGR62370.jpg (288.0 KB, 2 views)
GeorgeRa is offline   Reply With Quote
Old 04-20-2018, 02:51 PM   #48
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 11,917
Default

We don't have a GFCI, or breaker in the inlet line either at the cord or first in line in the van, but it certainly isn't a bad idea. Our inverter does have a 30 amp internal breaker, which is the first in line protection. There are no devices between the power cord plug and the inverter.

As for GFCI, when I updated our system to more batteries and larger inverter/charger, I put the entire van on GFCI by changing out all the breakers in the main breaker box to GFCI. The main is still a non GFCI.

IMO, in a situation like an RV, where you can be generating 120v power with no ground reference or path, it just plain makes sense to have everything on GFCI, regardless of how well you adhere to the good neutral/ground bonding practices.

We have not had any false tripping issues to this point and it has been a few years.
booster is offline   Reply With Quote
Old 04-20-2018, 11:35 PM   #49
Platinum Member
 
Join Date: Jul 2012
Posts: 2,380
Default

Just as a note, Roadtrek has stated that the inverters they install are not the generic models but have been modified to meet the standards required for installation in an RV. Not sure what standards they are referring to or whether they are industry standards or Roadtrek standards but the implication has always been that they are “improved” by these modifications over what you would get in the generic version.

Take this as you want...
gregmchugh is offline   Reply With Quote
Old 04-20-2018, 11:47 PM   #50
Platinum Member
 
Join Date: Mar 2018
Location: California
Posts: 132
Default

Quote:
Originally Posted by gregmchugh View Post
Just as a note, Roadtrek has stated that the inverters they install are not the generic models but have been modified to meet the standards required for installation in an RV. Not sure what standards they are referring to or whether they are industry standards or Roadtrek standards but the implication has always been that they are “improved” by these modifications over what you would get in the generic version.

Take this as you want...
The violation of the bill of materials is for the roadtrek installed inverter. It was tested with and should have been built with 10 gauge wire. 18 is both a code and delivery error.
ContinuousImprovement is offline   Reply With Quote
Old 04-21-2018, 12:13 AM   #51
Platinum Member
 
Join Date: Jul 2012
Posts: 2,380
Default

Quote:
Originally Posted by ContinuousImprovement View Post
The violation of the bill of materials is for the roadtrek installed inverter. It was tested with and should have been built with 10 gauge wire. 18 is both a code and delivery error.
I am just reporting what a very very senior management individual said about their inverter...

I have no idea if it means anything in practical terms...
gregmchugh is offline   Reply With Quote
Old 04-22-2018, 05:42 AM   #52
Platinum Member
 
Join Date: Mar 2018
Location: California
Posts: 132
Default

Quote:
Originally Posted by gregmchugh View Post
I am just reporting what a very very senior management individual said about their inverter...

I have no idea if it means anything in practical terms...
Your comment was good. Btw:. I'm very very senior too. Sometimes we are right.
ContinuousImprovement is offline   Reply With Quote
Old 04-22-2018, 05:41 PM   #53
Platinum Member
 
Join Date: Jul 2012
Posts: 2,380
Default

Interesting article on one RV manufacturer who seems to be doing the right things to improve...

https://www.truckcampermagazine.com/...announcements/
gregmchugh is offline   Reply With Quote
Old 04-22-2018, 07:21 PM   #54
Platinum Member
 
Join Date: Dec 2010
Posts: 2,058
Default

Quote:
Originally Posted by gregmchugh View Post
Interesting article on one RV manufacturer who seems to be doing the right things to improve...

https://www.truckcampermagazine.com/...announcements/
Greg-at one time i was researching truck campers. That truck camper manufacturer has remade themselves several times.
gerrym51 is offline   Reply With Quote
Old 04-22-2018, 07:54 PM   #55
Platinum Member
 
Join Date: Jul 2012
Posts: 2,380
Default

Quote:
Originally Posted by gerrym51 View Post
Greg-at one time i was researching truck campers. That truck camper manufacturer has remade themselves several times.
Yes, the company has an interesting history. I think a company in Colorado that makes a similar pop up lightweight truck camper is owned by people from an earlier encarnation of the original company. My daughter has a basic shell 4 Wheel Camper on her Ford Ranger, it is a very well made camper and maybe the only one light enough for her truck.
gregmchugh is offline   Reply With Quote
Old 04-22-2018, 07:57 PM   #56
Platinum Member
 
Join Date: Dec 2010
Posts: 2,058
Default

Quote:
Originally Posted by gregmchugh View Post
Yes, the company has an interesting history. I think a company in Colorado that makes a similar pop up lightweight truck camper is owned by people from an earlier encarnation of the original company. My daughter has a basic shell 4 Wheel Camper on her Ford Ranger, it is a very well made camper and maybe the only one light enough for her truck.
if i was buying one it would be Northstar. they are not innovative and they do not make slideouts-but they are by far the best built they have many pop ups AND their liberty high top would fit on the ford ranger
gerrym51 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 07:42 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.