Electrical/EMS Question

[rhagfo]

Originally Posted by LHaven

I've never owned a 50A rig. Are the legs arranged in two columns, or do they do even/odd positions like they do in residential?

Most RV services have the main in the middle and each half of the main feeds one side of the panel. Some very high end RV’s may have a panel laid out like a residential where the main is at one end or top and each leg feeds every other breaker. Those allow easy access to 240 volts for some appliances.

[TNordine]

I have a 2021 Cougar 24RDS with one a/c unit but the trailer is wired for 50amp. At my house I have a 30amp outlet that I plug a 30 amp cord into then a 30 to 50 amp dogbone. You guys are saying I would need a 50 amp ems?
BTW I have no problem running everything electrical off of this configuration.

[flybouy]

Originally Posted by TNordine

I have a 2021 Cougar 24RDS with one a/c unit but the trailer is wired for 50amp. At my house I have a 30amp outlet that I plug a 30 amp cord into then a 30 to 50 amp dogbone. You guys are saying I would need a 50 amp ems?
BTW I have no problem running everything electrical off of this configuration.

The only way to use a 30 amp EMS would be a plug in and not a hard wired EMS. If your trailer is wired with a 50 amp panel then it's likely wired for a second air conditioner. If in the future you added a second a/c unit then you will need to connect to 50 amps. Even without a second unit on 30 amps you cannot operate everything electrical on 30 amps, i.e. the a/c, the microwave, the water heater, the fridge, and the battery charger/converter. Being a 30 amp EMS would limit your options.

[MikeSmith]

Originally Posted by LHaven

A 50A circuit has two independent positive power connectors (legs); a 30A has one.

Even though your rig does not use more than 30A, the circuits inside it may be wired so that some devices/appliances/lights are assigned to one of those legs and the rest are on the other, so both legs have to work. It's not like one leg is reserved exclusively for your second AC and nothing else.

A 50A EMS monitors both those legs for happiness. A 30A EMS has only the connections capable of monitoring one of those legs, leaving the other unmonitored.

When you use a 50-to-30 adapter, it feeds both of your legs from the same single leg on the pedestal. So at best, your 30A EMS would protect half the stuff in your trailer, leaving the other half to fry. At worse, it would complain that there's something funny going on (like a GFI) and just shut down.

A fusible link is just a box full of smoke. Its job is to let out all that smoke when you screw up, to let you know you screwed up.

Very well worded. I deal with 3 phase 480v at work and understand completely about multiple “hot” legs but explaining it to those that don’t understand or wor work with it can be difficult. You did an excellent job breaking it down for the average person.

[meaz93*]

From my experience...a 50amp coach will run 1 AC and most appliances on 30amp service> but not both AC units; and if it does run it for a short time before blowing it may damage the Inverter overtime and or AC units themselves.
I've been at campgrounds that only had 30amp service available for my 50amp TT.
So I always pack my 30amp Surge Protector from the Springdale days and a 50/30amp dog- bone....just in case!
I like having the Southwire 40301 Wireless Bluetooth LCD Display in conjunction with the Southwire 34951 EMS to monitor all things electrical...and from inside the Outback.[emoji106]

[sourdough]

Originally Posted by meaz93*

From my experience...a 50amp coach will run 1 AC and most appliances on 30amp service> but not both AC units; and if it does run it for a short time before blowing it may damage the Inverter overtime and or AC units themselves.
I've been at campgrounds that only had 30amp service available for my 50amp TT.
So I always pack my 30amp Surge Protector from the Springdale days and a 50/30amp dog- bone....just in case!
I like having the Southwire 40301 Wireless Bluetooth LCD Display in conjunction with the Southwire 34951 EMS to monitor all things electrical...and from inside the Outback.[emoji106]
Attachment 41040Attachment 41041

I guess I'm too lazy and cheap but I need to get the 34951 with remote vs the one I have now without the remote. I suppose I will just buy one as I really would like to see those readouts vs running out and looking at the unit outside. I think the wireless display is worth it IMO.