Using Dryer's NEMA 14-30 outlet for RV shore power
Hey folks,
UPDATE:
Skip all the banter and jump to the CURRENT PLAN using this link!
Original Post:
I've been reading lots of posts about using dryer hookups for RV shore power at home and lots of them are outdated (using the older NEMA 10-30 outlets). This question is about the newer NEMA 14-30 hookups.
(Edited to add this DISCLAIMER: For the sake of clarity, I am a degreed electrical engineer with ~20yrs experience and have worked around electricity my entire life. I have done plenty of wiring jobs at my own house and at the houses of friends and family. I understand electricity and the risks involved significantly well. I do plenty of electrical work, but do draw the line at installation of a new subpanel or main service entrance. :) I believe this thread is entirely useful for others who may wish to install a NEMA 14-50 outlet in their garage (whether for their RV or their Tesla). But, if you are not qualified to work on electrical systems, PLEASE do not take this thread as a suggestion that such a job is easy and without significant risk. I will not, nor will any other contributor to this thread, be responsible for anything you do as a result of this thread.)
For reference..
OLD style:
Link: Wikipedia NEMA 10 Style
Example:
NEW style:
Link: Wikipedia NEMA 14 Style
Example:
My house (build circa 2007) has the newer style NEMA 14-30 connector. When I put a multi-meter on it, it measures like this:
That seems to me equivalent to the necessary 50A hookup on an RV (albeit with only 30A's "actual"):
It also seems to me that I could use a 2-phase (DPDT) 30A switch to switch between my dryer outlet (inside) and a RV outlet (garage), using a switch such as the Leviton 1288 to switch power between the dryer and the garage outlets.
Leviton 1288:
However, I read over and over about people frying their RV trying to hook up shore power various ways from their house. SO I wanted to try and clarify what I think would work and get feedback.
It seems to me that I can use my dryer dual-30A hookup to power a 50A RV hookup with the stipulation that it will be limited to 30A per leg at the breaker box.
To be clear, our goals would be:
It would seem to me that this circuit would be able to do the job.
My plan currently is:
Lastly, I want to again point out that this scenario would only supply 30A to each 120V leg even though we would be using a 14-50 style 50A RV hookup plug. This limitation comes from the breaker box itself. I cannot replace the breaker with a 50A because it would involve pulling new 50A wiring, and might violate dryer safety.
So, ..... thoughts?
cheers,
..dane
UPDATE:
Skip all the banter and jump to the CURRENT PLAN using this link!
Original Post:
I've been reading lots of posts about using dryer hookups for RV shore power at home and lots of them are outdated (using the older NEMA 10-30 outlets). This question is about the newer NEMA 14-30 hookups.
(Edited to add this DISCLAIMER: For the sake of clarity, I am a degreed electrical engineer with ~20yrs experience and have worked around electricity my entire life. I have done plenty of wiring jobs at my own house and at the houses of friends and family. I understand electricity and the risks involved significantly well. I do plenty of electrical work, but do draw the line at installation of a new subpanel or main service entrance. :) I believe this thread is entirely useful for others who may wish to install a NEMA 14-50 outlet in their garage (whether for their RV or their Tesla). But, if you are not qualified to work on electrical systems, PLEASE do not take this thread as a suggestion that such a job is easy and without significant risk. I will not, nor will any other contributor to this thread, be responsible for anything you do as a result of this thread.)
For reference..
OLD style:
Link: Wikipedia NEMA 10 Style
Example:
NEW style:
Link: Wikipedia NEMA 14 Style
Example:
My house (build circa 2007) has the newer style NEMA 14-30 connector. When I put a multi-meter on it, it measures like this:
That seems to me equivalent to the necessary 50A hookup on an RV (albeit with only 30A's "actual"):
It also seems to me that I could use a 2-phase (DPDT) 30A switch to switch between my dryer outlet (inside) and a RV outlet (garage), using a switch such as the Leviton 1288 to switch power between the dryer and the garage outlets.
Leviton 1288:
However, I read over and over about people frying their RV trying to hook up shore power various ways from their house. SO I wanted to try and clarify what I think would work and get feedback.
It seems to me that I can use my dryer dual-30A hookup to power a 50A RV hookup with the stipulation that it will be limited to 30A per leg at the breaker box.
To be clear, our goals would be:
- Park the RV in front of the house before/after trip for loading/unloading
- Have Lights, A/C, and fridge running while loading/unloading
- *NOT* planning on daily living use (microwave, etc)
It would seem to me that this circuit would be able to do the job.
My plan currently is:
- Turn off dryer circuit breaker (safety first!)
- Disconnect existing circuit from dryer outlet
- Connect circuit from breaker to a DPDT switch such as the Leviton 1288 (linked above)
- Connect one set of switch outputs to Dryer outlet
- Connect second set of switch outputs to Garage RV outlet
Lastly, I want to again point out that this scenario would only supply 30A to each 120V leg even though we would be using a 14-50 style 50A RV hookup plug. This limitation comes from the breaker box itself. I cannot replace the breaker with a 50A because it would involve pulling new 50A wiring, and might violate dryer safety.
So, ..... thoughts?
cheers,
..dane
