Trying to wrap my head around the surge suppresor

[HTX]

I installed the Progressive 50 amp on board surge suppressor even though I am running on a 30 service. It shows me two legs, with the AC on one will show 15-16 amps the other one 2-4 amps at any given time and anywhere from 117 to 126 volts depending on the load. With the AC off both show 2-4/5 amps. About the only thing running is the Dometic fridge and a few lights that are LED.

I've turned on 2 AC units and get 15/16 amps on both legs plus have been able to run a computer and TV's etc. at the same time but have only done that for a short period of time, 30-40 minutes.

I guess I am asking "What is the display really telling me?" And will it do what is supposed to do if load too much stuff at one time? Or does it need a full 50 amps in to work as advertised?

HTX

[spindrift]

Your Progressive is not monitoring your energy usage inside the coach. That job is the responsibility of your circuit breakers. The Progressive is monitoring "Source" or "Utility" voltage coming from your campsite pedestal towards your coach. In other terms, it's a one-way monitoring system. When that Utility voltage falls outside of critical parameters, it will interrupt flow to your main circuit panel and you will be without power until such time as the Progressive "see's" proper voltage.

[johnboytoo]

Yep, I think of it as a large filter - too low or too high it just blinks at me

but it is especially appreciated when a bad pedestal is wired wrong or out of phase

one on site guy told me your progressive is broken just remove it and plug into the pedestal without it...
I opted to move to another site where it worked fine

[Rick and Mindy]

Originally Posted by johnboytoo

Yep, I think of it as a large filter - too low or too high it just blinks at me

but it is especially appreciated when a bad pedestal is wired wrong or out of phase

one on site guy told me your progressive is broken just remove it and plug into the pedestal without it...
I opted to move to another site where it worked fine

Yeah, I was told that the surge protector was too precise and that is why it kept shutting my power down. This was in an Arkansas State Park. He told me to disconnect my surge protector and that would solve the issue. I asked if he was going to pay for damages in the event his pedestal burned up all the electronics in the RV and his answer was "NO!". I will not go back to that State Park because I checked many pedestals around mine and they were all spiking. Another fine case of customer service.

[atom ant]

Your coach is wired with two legs at the panel. On 50A, each leg is fed from a separate circuit, but on 30A both legs are fed from the same circuit, but they are still split in the panel and all the way back to the plug (or 30A adapter).

The Amp readouts are the same as if you were to place in induction type ammeter on each leg (those big carbon rings inside the surge box). It's telling you the consumption on that particular leg, even though the ultimate source of power may be the same on both legs.

Like spindrift said, the surge isn't necessarily looking for an overload, it's looking for fault. The surge should pick up spikes, ground fault, etc regardless of whether you are on 30A or 50A, but it may never care if you overload one of the legs.

[Pete385]

50A has 2 legs, neutral, ground. Each leg is 120v. With 2 AC units they would run each from separate legs. When a meter shows amperage it is usage, hence different reading on each leg if only one is running. When checking voltage it is supplied.
You may never get same reading from each leg depending on what is turned on.

Same with 30A except they don't always have neutral and ground, but always 2 legs.

The exception to all of this is if you are running a 240V appliance and that would draw equally from each leg (unless there were 120V control circuits on one leg).

[atom ant]

Originally Posted by Pete385

50A has 2 legs, neutral, ground. Each leg is 120v. With 2 AC units they would run each from separate legs. When a meter shows amperage it is usage, hence different reading on each leg if only one is running. When checking voltage it is supplied.
You may never get same reading from each leg depending on what is turned on.

Same with 30A except they don't always have neutral and ground, but always 2 legs.

The exception to all of this is if you are running a 240V appliance and that would draw equally from each leg (unless there were 120V control circuits on one leg).

The RV 30A supply is only 1 leg, neutral and ground. it only splits into 2 legs when it gets to your trailer cord on a 50A trailer.

[Pete385]

Put a meter on it. Each flat blade to ground(round). 30A

[Pete385]

The breaker in the pedestal is 2 pole 30A or 2pole 50A
A 2 pole breaker is indicative of two hot legs

[atom ant]

I sure hope your RV pedestal does not have a 2-pole 30A breaker, or there are a lot of smaller 30A rigs in the campground that are in big trouble right now with smoke coming from them Plugging an RV into a 2-pole 30A circuit will send 240VAC through the rig because they are only wired with a single leg.

Unlike 50A, the 30A RV has always been unique to RVs and is a 1-pole 30A supply with a different style receptacle than household type outlets for range tops, etc.

Here is the pedestal I am at - 2-pole 50A, 1-pole 30A, and 1-pole 20A

[Pete385]

OK. How does the 30A to 50A adapter work?

[ted 95]

Generally a campground will not supply 30a 2 pole 4 wire 240v plug because the configuration is not the same as a 50a 2 pole 4 wire 240v. Or only supply 30a on a 50a configuration as you will trip their beaker constantly. If you are suggesting the plug is wired 2 hots and a ground on a 30a 1pole 120v. That is impossible as you would fry your panel.

[HTX]

Thanks! That helped a lot now I can go wrap my head around some other issue.

[atom ant]

Originally Posted by Pete385

OK. How does the 30A to 50A adapter work?

Basically like this - the 30A/50A dogbone adapter takes the hot on the one pole of the 30A and energizes both poles on your 50A cord.

That is why a 30A RV service outlet only supports up to 30A of 110VAC devices, even when using the dogbone, whereas a 50A RV service outlet can power up to 100A of 110VAC devices because it is actually 2 poles of 50A.

[atom ant]

Here is some info a little more technical than my explanation - The 30-amp 120-volt 2 pole 3 wir

The 30-amp 120-volt 2 pole 3 wire RV service

The 30-amp service for an RV is 120-volt with a 3 prong receptacle and a single 30-amp dedicated breaker. The 30 AMP is a standard ANSI C73.13, TT-30P (plug) / TT-30R (receptacle). This designation was made specifically for TRAILERS. Plugs and Receptacles are available at Lowe's, Home Depot, Camping World and Electric Supply houses.

The TT–30 is a 30A, 120-volt recreational vehicle standard sometime it is called simply RV 30. Frequently it is confused for a NEMA 10–30 with disastrous results. Due to the appearance of the TT-30 plug, many people assume that it is to be wired for 240-volt, but this is a 120-volt device.

It is imperative that the Electric Service used for RV’s are wired correctly. DO NOT TRUST anyone, yourself, friends, relatives or ANY Professional Electrician. ALWAYS check out all RV Electric Service BEFORE plugging in the first time. The majority of the mistakes and the most damage to the RV’s are made with the incorrect installation of the 120-volt 30 amp Service. For some reason people including Electricians just DON’T GET IT when it comes to the 30-amp 120-volt Service. All you need to do is look at the online Forums where RV’s were damaged by incorrect installations.

Many times the 30-amp 120-volt Service is confused with the OLD 3 wire 120/240-volt Appliance Service. Even if you purchase the correct TT-30 receptacle it may get wired incorrectly with 2 HOT lines. It is harder to make mistakes with the 50-amp 120/240-volt installation but people do screw things up. As long as all the wires are connected to the correct terminals and everything checks out it will work.