Can I plug my 50amp cord from my class A into a dryer outlet?

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DonTom

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'm sure a lot of things would have been different if you had been in charge with the ability to predict the future.
Perhaps they will someday phase out the RV-30 and we will only have the 100 amps total of 14-50R. Perhaps it has already started to a small degree. But I doubt if I will live long enough to not see any RV-30 outlets.

-Don- Crescent City, CA
 

NY_Dutch

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Perhaps they will someday phase out the RV-30 and we will only have the 100 amps total of 14-50R. Perhaps it has already started to a small degree. But I doubt if I will live long enough to not see any RV-30 outlets.

-Don- Crescent City, CA
You won't live long enough to see no more 30 amp RV's, so I don't expect you'll ever see no more 30 amp RV outlets either. The extra expense to have a 30 amp outlet along with 50 amp and 15/20 amp utility outlets is minimal.
 

DonTom

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The extra expense to have a 30 amp outlet along with 50 amp and 15/20 amp utility outlets is minimal.
I have no issue when they have both. It's when they only have 30-amp, like the place I am at right now. But I think they do have a few 50/100-amp (12,000 watt) sites that are already taken.

I wonder why they didn't use watts from the start with RV outlets.

-Don- Crescent City, CA
 

Ex-Calif

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But with the four-prong, you have two places that can fail instead of only one. But I think you mean both are unlikely to fail at once on the four-prong.

Example:

Pf1 = 0.10 + Pf1 = 0.20 = Probability of single failure

Pf1 X Pf1 = 0.010 = Probability of dual failure

I did this stuff for years and years. One can argue that for two new connections that the MTBF would be the same and they would fail concurrently. Simple variation in assembly and environment ensure the probability of wear out modes causing a double failure is essentially zero mathematically.

In order to get a double joint failure in a plug you would have to do something wrong.

The whole concept of flying twin engine airplanes across oceans is based on this math.

I've studied thousands of engine stoppages and the 10s of multi engine stoppages.

Multi engine stoppages tend to be error - out of fuel or oil - or environment - flew into a volcanic cloud of flew into known icing beyond the capability of the airplane.

But the ground can still fail on either and is just as likely. So is having the neutral still connected without a ground somehow still considered safer? If so, why?

-Don- Crescent City, CA

In a 4 wire system the N and G are bonded at the main service panel. A 4-prong plug offers a redundant path compered to the 3 wire.
 

Ex-Calif

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The 240 VAC systems I'm familiar with have one hot 240v lead and a return at 0 volts. Just like North America's 120 volt system but at twice the voltage.
Home electric dryers didn't become wide spread until well into the 1960's, so I'd expect the 240 dryer outlet was standardized around the same time frame. Most of the world has standardized on 220-240 VAC (with no neutral by the way) with only North America and a few others using 120 VAC derived from 240 VAC.
future. Lacking that ability though... ;)

Yeah I was gonna call foul on this as well.

One could look at US house mains like the RV. Technically we get 2 X 120V legs, 1 X Neutral Leg. We stake a ground bar into the ground to make up the 4th connection.

In Australia they deliver 240V on one leg and Neutral on the other leg into the house. They also call ground Earth.

1660156370373.png
 

Pedro Dog

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I'm going to try and explain how things are/should be. Excuse my poor illustrations. the first drawing is of a 4 prong wired dryer. Notice no current on ground wire

Typ Wiring.jpg
 

Pedro Dog

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This is what happens when a hot shorts to the dryer chassis.

Current now flows through the ground wire and trips the circuit breakers. This prevents electrocution

Line short.jpg
 

Pedro Dog

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This is what happens when the neutral shorts to the dryer chassis.

Current flows through both the neutral (unless it breaks off and shorts) and ground wire. This will not trip the circuit breakers but cause a dangerous situation where the dryer chassis is hot.

Remember the video where the guy had current flowing through pipes, this is that situation.

Neutral Short.jpg
 

DonTom

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In a 4 wire system the N and G are bonded at the main service panel. A 4-prong plug offers a redundant path compered to the 3 wire.
OIC. So the neutral is always grounded anyway, regardless if 3 or four prong, so it really is two grounds.

I ain't an electrician so I didn't know the neutral was always grounded regardless of anything else.

-Don- Crescent City, CA
 

DonTom

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Pf1 X Pf1 = 0.010 = Probability of dual failure
Not always so simple.

Such as if the redundancy is what caused the complete failure!

For an example, a failed A-B relay so neither gets selected. I have seen it happen with a police base station, knocking the channel out of service.

The problem with redundancy is 51% of problems are because of the redundancy! ;)

-Don- Crescent City, CA
 

DonTom

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I have been complaining here about nothing! I totally forgot I do NOT have to unplug my electric motorcycle to do anything at all on the mickey-mouse RV-30 outlet here.

I just took a shower and didn't want to go outside to unplug my charging bike to dry my hair. I have been riding the bike most of the day and used up 60% SOC.

So I used my brain for a change, instead! o_O

I somehow forgot about my inverter on my 300 AH battery! I didn't think about it just because I am not boondocked. I just dried my hair with my hair drier from my inverter. The one I added.

I watched my Victron as I dried my hair.

At 12V lith battery:

1,574 watts.
127.20 amps.

Voltage drop of 1.0 volt.

Rest voltage was 13.22 volts
12.22 under the load above.

The hair drier says it is rated at 1875 watts. But my 1,574- 12VDC watts worked very well for hair drying.

My MW oven is 1550 watts. So there will be no problem there either.

So I have no need for the 50 amp (or hair drier outlet) here.

Somehow, battery recovered to 13.29 volts in a few seconds after the load was removed. Even more than the 13.22 I started with, says my Victron SmartShunt.

-Don- Crescent City, CA
 

Ex-Calif

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Not always so simple.

Such as if the redundancy is what caused the complete failure!

For an example, a failed A-B relay so neither gets selected. I have seen it happen with a police base station, knocking the channel out of service.

The problem with redundancy is 51% of problems are because of the redundancy! ;)

-Don- Crescent City, CA

Don - If you are saying that the A/B relay is a single device that selects circuit A or backup circuit B then that is not redundancy.

Redundancy is a system that is completely separate and is immune to single point failures.
 

Pedro Dog

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Avatar is a few years old. I was blessed with a full head of thick hair. I cut it myself, #8 on top, #5 on the sides and #3 around the ears and back. After washing it, it's towel dry and that's it.
 
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