30 AMP or 50 AMP connection.

[Mustang65]

Most volt meters have options to read Volts, DC Amps and Ohms. Those small inexpensive meters have a max of 10 Amps/DC. They do not read AC amps.

Don

My Registry

RVing with SOLAR

 

[bedrck46]

Most volt meters have options to read Volts, DC Amps and Ohms. Those small inexpensive meters have a max of 10 Amps/DC. They do not read AC amps.

Don

My Registry

RVing with SOLAR

DON I do disagree with your statement!!

A VOLTMETER Will only read VOLTS
A AMPMETER will only read AMPS
A OHMMETER will only read OHMS

HOWEVER A MULTIMETER WILL READ ALL THREE BUT MOST MULTIMETERS are limited in what they can read IN AMPS.

The statement(that was posted earlier by another member) saying "Your amperage can be measured with a voltmeter"
is also wrong.

To read AMPS you need either a amp meter properly hooked up in the line or a CLAMP ON AMPMETER that needs to be clamped on one leg of the incoming voltage line

 

[Mustang65]

DON I do disagree with your statement!!

A VOLTMETER Will only read VOLTS
A AMPMETER will only read AMPS
A OHMMETER will only read OHMS

HOWEVER A MULTIMETER WILL READ ALL THREE BUT MOST MULTIMETERS are limited in what they can read IN AMPS.

This is very true...but in most cases, Volt meter is the commonly used term to cover all the above. Not that it is correct, just the way it is used now. 99.% of its use is to check for voltage, which is probably why it is generally called the Volt meter.

Back when I was going to DeVry (yes they had electricity then) it was known as a VOM (Volt Ohm Meter, which used tubes in its circuitry, remember them, probably not... it took 5 minutes for the tubes to warm up and then you calibrated it, before using it) it also measured Amps, volts, ohms. The next generation was TRVM (Transistorized Volt Meter) again, it was used to measure, Volts, Ohms and Amps. Then it went to Multi-meters, which is by far the most accurate name for it.

In general conversation, especially in a lot of the posts on this site and others, the term Volt meter is used as a generic name which covers all the above, but by its name it can be deceiving.

Good catch!

Don
My Registry

RVing with SOLAR

 

[bedrck46]

Don Careful your giving your age away
Rumor has it you were just a teenager when the Dead Sea was just sick


And yes I remember


One of the first meter I used was a Simpson 260


I have mainly used the term meter or multi meter Comes from being in the navy when we used the old


Ideal 61-076 Vol-con tester AKA Wiggy Voltage Tester

 

[shrpshtr]

So, a constructive comment on this theory to try to help everyone understand a little more. The breaker protects the wiring and the devices. If you have a 30amp main breaker, the device (your RV) cannot draw more than 30 amps, so your cable is protected. Amperage from a 50A pedestal does not run down the wire and stop at your main breaker (think of water against a dam and then understand that electricity does not work exactly that way.)

The power is drawn by the device (your RV) as required. There's not 50A of power sitting there cooking your cable when it's not being demanded by your device. So, the thought about "losing some protection for your cord" should be further considered and then dismissed. You can't really draw more than 30A (from a 50A outlet, or even a 1000A outlet for that matter) if your main breaker is 30A. Once you draw about 85-90% of the amperage (or so, manufacturers differ) you will trip the main and stop the flow of current.

If that were not the case, there would be no such thing as dogbones to get you from 50 to 30 or even 15, because every one of us would then be starting fires. If you plug your 120v appliance directly to a pedestal using a 15F to 50M dogbone (I have one) and all 50A (100A if both legs used) was somehow "backed up" in the cord, you would then immediately burn up the cord and the appliance. However, this does not happen because the appliance only draws the current it needs and therefore the wire is not burdened with all the amperage available on the outlet on the pedestal.

Think of electricity like you think of plumbing.

Voltage is measured in volts, current is measured in amps and resistance is measured in ohms.

An analogy to help understand thinking about plumbing pipes. The voltage is similar to the water pressure, the current is similar to the flow rate, and the resistance is like the pipe size.

Look here for a lot more detail than you probably want.
Water circuit analogy to electric circuit
Water circuit analogy to electric circuit

In any case, the only time wire sizes come into play is when the current (AMP flow) is greater than the wire's rated size. I can hook my cell phone charger to a 1000A supply, but it's only going to draw 2.1A, so my wire is safe.

Under normal operating conditions anyway...

 

[wags999]

So, a constructive comment on this theory to try to help everyone understand a little more. The breaker protects the wiring and the devices. If you have a 30amp main breaker, the device (your RV) cannot draw more than 30 amps, so your cable is protected. Amperage from a 50A pedestal does not run down the wire and stop at your main breaker (think of water against a dam and then understand that electricity does not work exactly that way.)

The power is drawn by the device (your RV) as required. There's not 50A of power sitting there cooking your cable when it's not being demanded by your device. So, the thought about "losing some protection for your cord" should be further considered and then dismissed. You can't really draw more than 30A (from a 50A outlet, or even a 1000A outlet for that matter) if your main breaker is 30A. Once you draw about 85-90% of the amperage (or so, manufacturers differ) you will trip the main and stop the flow of current.

If that were not the case, there would be no such thing as dogbones to get you from 50 to 30 or even 15, because every one of us would then be starting fires. If you plug your 120v appliance directly to a pedestal using a 15F to 50M dogbone (I have one) and all 50A (100A if both legs used) was somehow "backed up" in the cord, you would then immediately burn up the cord and the appliance. However, this does not happen because the appliance only draws the current it needs and therefore the wire is not burdened with all the amperage available on the outlet on the pedestal.

Think of electricity like you think of plumbing.

Voltage is measured in volts, current is measured in amps and resistance is measured in ohms.

An analogy to help understand thinking about plumbing pipes. The voltage is similar to the water pressure, the current is similar to the flow rate, and the resistance is like the pipe size.

Look here for a lot more detail than you probably want.
Water circuit analogy to electric circuit
Water circuit analogy to electric circuit

In any case, the only time wire sizes come into play is when the current (AMP flow) is greater than the wire's rated size. I can hook my cell phone charger to a 1000A supply, but it's only going to draw 2.1A, so my wire is safe.

There is a small possibility of pulling more than 30 amps in your cord IF something happens to the cord, ahead of your RV breaker, it would pull the maximum the pedestal breaker would allow. It would not be something I would worry about, but it is possible to draw more power than your cord is rated for.

 

[nwminnesota]

Interesting read. Some false and true information above.

I am not 100% sure what the op was asking and what his electrician told him.

If you have a 30 amp circuit you can draw up to 30amps from it no problem. However if you sart to go over 30amps lets say 31 amps I bet you that you can draw that for an hour or indefeintly depending on ambient temp where the circuit breaker is, age of circuit breaker and how many times it has tripped. The higher above the 30 amps you go the faster it will trip.
So if you have a 30amp circuit you can draw up to 30 amps of power. However when sizing a circuit for continuous loads you have to size the circuit 20% more so another words if your continuous load should never exceed 80% of your circuit per NEC.
Pluging your 30amp cord in 50amp receptacle and your 30amp cord is not protected at 30amps you could potentially over load your cord.

Excuse my spelling and grammar. ..

 

[Mustang65]

That set me to thinking. So, I'm wondering. [B]If prepared with a 50 to 30 amp dog bone, would it be beneficial to use the 50 amp service and plug the coach to the 30 amp side of the dog bone? Would that give me a total 30 amps of power or am I just wasting my time?[/B]

Reaching out to those with experience ......

On my TT the 30Amp breaker trips at 28 amps, based on the data it recorded when the Microwave was running and the AC kicked on. There were a few other things running also. So, based on the 28Amps (close enough to 3 amps), if I were to plug my 30Amp shore-power cable into the 50 amp pedestal outlet, I would still trip the breaker inside the TT at 28Amps. No gain here.


The unknown here is at what amount of Amps does it take to trip the pedestal's 30Amp breaker? 28Amps? 27Amps? .... I have yet to trip a pedestal breaker, which to me indicates that I am operating on the safe side of 30Amps.

My question is why do you want to go to 50 amps? Are you tripping breakers in your RV? In the pedestal? Adding a 2nd AC unit?

If you are having electrical issues, try a little planning.. like don't use the microwave with the AC on, move the thermostat setting from AC to FAN mode while using the microwave or hair dryer.. as we do. It just takes a little thinking (not much labor involved).

If you are not into adapting to coordinating high wattage items and when they can or can not be used, you can convert your RV to a REAL 50Amp hookup. This would take a little extra wiring and an electrician could do it very easily, or if you can work with 110VAC wiring you could do it yourself. Just move the AC to its own 50Amp circuit (and 20Amp sub panel and run a heavier gauge wire from the newly installed 50Amp receptacle mounted on the RV to the RV's existing 110VAC service panel. Now you have the proper wiring inside the RV. Then purchase a 50Amp Shore-power cable to use.

BUT you will still need a 30Amp to 50Amp dogbone for those CG's that do not have 50Amp service.

If you are not having electrical issues, don't do anything and enjoy camping.

Don

My Registry

RVing with SOLAR

 

[RayBo-JAY]

Correct.

 

[RayBo-JAY]

There is a small possibility of pulling more than 30 amps in your cord IF something happens to the cord, ahead of your RV breaker, it would pull the maximum the pedestal breaker would allow. It would not be something I would worry about, but it is possible to draw more power than your cord is rated for.

I agree and don't refute you. However, life and "lightning" happens so we try to plan things that won't start us a biggole fire. At least so I think. Regardless, there is no need to fear hooking your 30A to a 50A dogbone, because what I said earlier is still true. If you have a lightning strike or a major short to ground, different story. But, that's about 1% of the time, most. You're not going to draw any more than your "device" needs, so the wire gauge doesn't matter unless you have additional draws.

 

[wags999]

We have the '16 Greyhawk MV with 30 amp service. In a conversation with an electrician, he stated that using 30 amp service will not give you a full 30 amps of power. He stated that same goes for 50 amp service.

That set me to thinking. So, I'm wondering. [B]If prepared with a 50 to 30 amp dog bone, would it be beneficial to use the 50 amp service and plug the coach to the 30 amp side of the dog bone? Would that give me a total 30 amps of power or am I just wasting my time?[/B]

Reaching out to those with experience ......

If your power is 120 volts it will give you 30 amps of power, actually a little more for a short period of time. Breakers work on electromagnetic energy to trip them. If the voltage is running below 120 volts, which is very common in busy campgrounds, then yes, you would not have a full 3600 watts, or 30 amps of power due to the voltage drop. You would gain Zero by plugging into a 50 amp receptacle, since the breaker in your RV would still only allow 30 amps to 120 volts or less than 30 amps if the voltage dropped below 120 volts. Actually what your concerned about is the wattage available. 30 amps at 120 volts gets you the full 3600 watts of power. As the voltage drops you multiple voltage by amps to get available wattage. Wattage is the amount of power your appliances will use.

Perhaps that is what your electrician was trying to say. I was an licensed electrician for 25 years. The voltage typically is not much different between a 30 amp or 50 receptacle in the same pedestal.

I would carry a 50 amp dog bone for reasons others have stated, but, to gain power would not be one of them.

Your RV will only allow 3,600 watts of power maximum, no matter what you plug into.

Plug into the respective receptacle for your RV unless there is an issue with that receptacle at the pedestal.

Happy Camping.

 

[RayBo-JAY]

There is a small possibility of pulling more than 30 amps in your cord IF something happens to the cord, ahead of your RV breaker, it would pull the maximum the pedestal breaker would allow. It would not be something I would worry about, but it is possible to draw more power than your cord is rated for.

Not the truth. If you have a breaker, like we all do, it is rated at a certain amperage, so you can not draw more than the power cord is rated because of your main breaker. PM me if you can't understand that and I'll explain, but don't keep spreading fear to people that somehow "greater power" is going to cook them. Power in can't exceed power out.

Your threat is just not the truth. A breaker BREAKS the circuit when the flow (AMPS) gets too high. Most pedestals are GFCI, so even if you cut the cord and sink it under water, you're still going to trip the breaker. It's incredibly simple, please don't scare people with unresearched rhetoric.

 

[wags999]

Not the truth. If you have a breaker, like we all do, it is rated at a certain amperage, so you can not draw more than the power cord is rated because of your main breaker. PM me if you can't understand that and I'll explain, but don't keep spreading fear to people that somehow "greater power" is going to cook them. Power in can't exceed power out.

Your threat is just not the truth. A breaker BREAKS the circuit when the flow (AMPS) gets too high. Most pedestals are GFCI, so even if you cut the cord and sink it under water, you're still going to trip the breaker. It's incredibly simple, please don't scare people with unresearched rhetoric.

Your 100% incorrect. If the cord got cut from being run over or damaged it would pull the maximum the pedestal breaker would allow. The breaker in your RV only protects from the breaker and beyond, not before. I'm not spreading fear I'm telling the truth. May want to understand what a breaker does, it protects from that point and down stream, not upstream. Accidents, shorts, damage does happen, not often but it does. In your example a wire coming from the electric pole into your home which had a 200 amp breaker could never carry more power than 200 amps....100% totally wrong. If shorted it would have 1000,0s of amps available.


If you cut the cord and sink it in water if till pull the amount of power (in this case 50 amps) available at the pedestal not the 30 amp breaker on the RV.

 

[nwminnesota]

Your 100% incorrect. If the cord got cut from being run over or damaged it would pull the maximum the pedestal breaker would allow. The breaker in your RV only protects from the breaker and beyond, not before. I'm not spreading fear I'm telling the truth. May want to understand what a breaker does, it protects from that point and down stream, not upstream. Accidents, shorts, damage does happen, not often but it does. In your example a wire coming from the electric pole into your home which had a 200 amp breaker could never carry more power than 200 amps....100% totally wrong. If shorted it would have 1000,0s of amps available.


If you cut the cord and sink it in water if till pull the amount of power (in this case 50 amps) available at the pedestal not the 30 amp breaker on the RV.

X2,, wags999 is right. I don't think he is trying to scare anyone. He is just telling you how it works. The cord that is plug in to the 50amp receptacle will be protected by the 50amp breaker that feeds the receptacle. When you have a short circuit it can be upwards towards 10,000amps look at the side of the breaker and it will have an interrupting rating.

Excuse my spelling and grammar. I'm just a dumb master electrician.

 

[wags999]

The confusion comes in because he believes your RV breaker is protecting the cord. I'ts not, it's protecting everything AFTER it enters your RV breaker.

The pedestal breaker most likely is connected to a 60 amp breaker at the campground main box. Camp sites are typically daisy chain wired...meaning every other campsite is wired together. Each main at the campground main box controls two camp sites (for that amp receptacle). What the means, is, when your working on the breaker you have 60 amps of power available, not 30 that is the breaker size.

The thing to remember is, whatever you plug into, that is what your cord can POTENTIALLY carry, until the next breaker is hit, then after that breaker it is protecting the system.

When plugged into a 50 amp receptacle with a 30 amp RV cord you would be using one of the legs in that 50 amp receptacle, thus, exposing your cord to 50 amps at 120 volts. IF your cord shorts ahead of the RV breaker it COULD pull the full 50 amps of power before the pedestal breaker would trip...the RV breaker may never trip in this example.

Best policy is to always plug into the appropriate receptacle when it's safe. You gain nothing in power by plugging into a higher amperage receptacle. IF, the 30 amp receptacle is damaged then, I would use a dog bone to connect to the 50 amp receptacle. BUT I would also IMMEDIATELY notify the campground and hopefully they would rectify the problem so you can use the appropriate receptacle.

Happy Camping

thank you nwminnesota for corroborating what I said.

 

[Robbbyr]

Most pedestals are GFCI, so even if you cut the cord and sink it under water, you're still going to trip the breaker.

I have not encountered campground pedestals that have GFCI protection on the 30- and 50-amp outlets. GFCI protection is very common (usually code-required) on the household-style 20-amp receptacle in the box, but not on the RV outlets. It also isn't recommended to "daisy chain" GFCI outlets, can cause unneeded GFCI trips when there isn't a true ground fault. And if the 30- and 50-amp outlets were GFCI-protected you would have that situation since circuits in the RV are GFCI protected.

And in my long career as a firefighter I saw numerous occasions where a structure's electrical service was pulled down and damaged. Literally sitting there on the ground incinerating itself. No pole breaker was tripped since it did not reach the trip threshold. Also never tripped the house or building's main breaker since there was no overload downstream. They would fry until they finally burned through. Several times the wires set the grass on fire! Can that scenario be scaled down to RV level? Yes, I've seen it.

I have seen where a damaged cord can heat up and cause damage without tripping the pedestal breaker. The "load" on that circuit is the short circuit or excessive resistance, in addition to any RV load there might be. Exceed the pedestal breaker rating, it will "pop" and open the circuit. Can it heat up and damage the wire without popping the pedestal breaker, absolutely! I have seen RV power cables that were turned into "crispy critters" unbeknownst to the camper until they broke camp and found their cord literally fall apart as they picked it up! No blown breakers in the RV or at the pedestal!

 

[Vicr]

X2,, wags999 is right. I don't think he is trying to scare anyone. He is just telling you how it works. The cord that is plug in to the 50amp receptacle will be protected by the 50amp breaker that feeds the receptacle. When you have a short circuit it can be upwards towards 10,000amps look at the side of the breaker and it will have an interrupting rating.

Excuse my spelling and grammar. I'm just a dumb master electrician.

X2
EL01 Licenced Journeyman Electrician
IBEW Local 46
Seattle, WA
35 Years experience in the field

 

[Vicr]

The confusion comes in because he believes your RV breaker is protecting the cord. I'ts not, it's protecting everything AFTER it enters your RV breaker.

The pedestal breaker most likely is connected to a 60 amp breaker at the campground main box. Camp sites are typically daisy chain wired...meaning every other campsite is wired together. Each main at the campground main box controls two camp sites (for that amp receptacle). What the means, is, when your working on the breaker you have 60 amps of power available, not 30 that is the breaker size.

The thing to remember is, whatever you plug into, that is what your cord can POTENTIALLY carry, until the next breaker is hit, then after that breaker it is protecting the system.

When plugged into a 50 amp receptacle with a 30 amp RV cord you would be using one of the legs in that 50 amp receptacle, thus, exposing your cord to 50 amps at 120 volts. IF your cord shorts ahead of the RV breaker it COULD pull the full 50 amps of power before the pedestal breaker would trip...the RV breaker may never trip in this example.

Best policy is to always plug into the appropriate receptacle when it's safe. You gain nothing in power by plugging into a higher amperage receptacle. IF, the 30 amp receptacle is damaged then, I would use a dog bone to connect to the 50 amp receptacle. BUT I would also IMMEDIATELY notify the campground and hopefully they would rectify the problem so you can use the appropriate receptacle.

Happy Camping

thank you nwminnesota for corroborating what I said.

X2, and I have the license to back them up.

 

[Vicr]

I have not encountered campground pedestals that have GFCI protection on the 30- and 50-amp outlets. GFCI protection is very common (usually code-required) on the household-style 20-amp receptacle in the box, but not on the RV outlets. It also isn't recommended to "daisy chain" GFCI outlets, can cause unneeded GFCI trips when there isn't a true ground fault. And if the 30- and 50-amp outlets were GFCI-protected you would have that situation since circuits in the RV are GFCI protected.

And in my long career as a firefighter I saw numerous occasions where a structure's electrical service was pulled down and damaged. Literally sitting there on the ground incinerating itself. No pole breaker was tripped since it did not reach the trip threshold. Also never tripped the house or building's main breaker since there was no overload downstream. They would fry until they finally burned through. Several times the wires set the grass on fire! Can that scenario be scaled down to RV level? Yes, I've seen it.

I have seen where a damaged cord can heat up and cause damage without tripping the pedestal breaker. The "load" on that circuit is the short circuit or excessive resistance, in addition to any RV load there might be. Exceed the pedestal breaker rating, it will "pop" and open the circuit. Can it heat up and damage the wire without popping the pedestal breaker, absolutely! I have seen RV power cables that were turned into "crispy critters" unbeknownst to the camper until they broke camp and found their cord literally fall apart as they picked it up! No blown breakers in the RV or at the pedestal!

Completely true Robby. There are also breakers that don't trip at all! Zinsco, Pushmatic, Bulldog and Stab-lok are all know to have caused fires because they did not trip. For some reason people on these boards like to argue with experts.

 

[wags999]

I have not encountered campground pedestals that have GFCI protection on the 30- and 50-amp outlets. GFCI protection is very common (usually code-required) on the household-style 20-amp receptacle in the box, but not on the RV outlets. It also isn't recommended to "daisy chain" GFCI outlets, can cause unneeded GFCI trips when there isn't a true ground fault. And if the 30- and 50-amp outlets were GFCI-protected you would have that situation since circuits in the RV are GFCI protected.

And in my long career as a firefighter I saw numerous occasions where a structure's electrical service was pulled down and damaged. Literally sitting there on the ground incinerating itself. No pole breaker was tripped since it did not reach the trip threshold. Also never tripped the house or building's main breaker since there was no overload downstream. They would fry until they finally burned through. Several times the wires set the grass on fire! Can that scenario be scaled down to RV level? Yes, I've seen it.

I have seen where a damaged cord can heat up and cause damage without tripping the pedestal breaker. The "load" on that circuit is the short circuit or excessive resistance, in addition to any RV load there might be. Exceed the pedestal breaker rating, it will "pop" and open the circuit. Can it heat up and damage the wire without popping the pedestal breaker, absolutely! I have seen RV power cables that were turned into "crispy critters" unbeknownst to the camper until they broke camp and found their cord literally fall apart as they picked it up! No blown breakers in the RV or at the pedestal!

I can only speak of campgrounds out west, but I agree with you, I have never seen a campground that has GFCI on 30 or 50 amp receptacles. In fact it's rare even on the 20 amp outlet. We did install a few 30 am GFCi breakers and had issues about 40% of the time. A RV would come in and plug in and it would trip the breaker. They had issues inside the RV, the guy before him and after him had no issues..it got so frustrating having to either swap out the breaker or moving them to another site we gave up and took the GFCI breakers out.

Daisy chaining is not on GFCI lines, but is typical on all of the receptacles. Two camp sites controlled in the main panel by one breaker. My guess is to save running multiple lines, it does work well 99% of the time.

You are correct I have also seen plugs melted from loose outlets or damaged plugs...

Thank heavens the vast majority of time there are no issues or at least no major issues.

Spring training camps open in a couple of weeks... spring is just around the corner ! Time to start making those camping plans