Proper 120 VAC connection process?

[TxCowboy]

Initially posted this in a related thread where Erika had a bad experience with her 120 volt AC system that caused some damage. Didn't want to detract from that thread so I'll repost my question(s) here.

Some folks are saying that you should turn off the 50 amp breaker (at the park's box, I assume). Why?

I always plug the surge protector into the park's power box first just to test the circuit there. If the park's electrical system fails the surge protector's built-in test (via five lights on the protector), I don't plug it into the RV.

Then I unplug the surge protector from the park's power, connect the 50 amp cable to the surge protector, check to make sure all of the connections are tight, then, and only then, I connect to the park's AC power.

Connecting to the park's AC power takes only a split second.

Have I been doing this wrong?

 

[JohnDar]

I prefer to do it in sequence, starting with turning off the pedestal breaker as well as the main breaker in the rig. Then plug in the shore line and turn on the pedestal. That feeds to the hardwired Progressive surge protector and I can check the display. Then I turn on the main breaker.


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[TxCowboy]

And for those of us with the "plug and play" model of surge protector?

And by "breaker", you mean the 50 amp on the RV, right? Sorry if this question seems obvious but I want to be clear which 50 amp you are referring to...

 

[brianharrison]

It is good practice to flip the 50A breaker on the campground pedestal to its off position before any connections are made to the pedestal. That way the circuit and plug that you are connecting are not live, and the chance of electrical arcing or incidental contact with the plug prongs once they are energized are eliminated. The breakers are designed to connect the electrical line/load in a safe manner.

Sequence of connecting your cords, portable surge protector is then in what ever sequence that works for you; I usually connect all the pieces together and then plug into pedestal and finally flip the breaker to the on position. The surge/power management system will protect the trailer.

The sequence that you outline goes the extra mile and checks park power condition with your portable surge before you connect your RV - if you feel comfortable using the extra steps, then why change?

John does something similar by turning off the 50A house breaker (in his trailer, downstream of his hardwired surge/EMS), letting it check park power condition, before he flips his house breaker to energize the rest of the trailer.

Brian

 

[TxCowboy]

The sequence that you outline goes the extra mile and checks park power condition with your portable surge before you connect your RV - if you feel comfortable using the extra steps, then why change?

Brian

Hi, Brian! That's the way I've been doing it -- testing first then connecting everything. Was wondering (again, based on comments in Erika's thread) whether I'd been doing it wrong all these years. LOL

Paranoid, I guess, but it only takes one mistake to have a serious problem.

 

[avvidclif]

Hi, Brian! That's the way I've been doing it -- testing first then connecting everything. Was wondering (again, based on comments in Erika's thread) whether I'd been doing it wrong all these years. LOL

Paranoid, I guess, but it only takes one mistake to have a serious problem.

Anytime something is plugged into a live circuit there is a small arc when contact is made. Those small arcs can cause problems as they accumulate. Look at the male ends of your plugs for the marks. Another thought, breakers are not designed to be switches and used as such. My 2 cents worth.

I make sure the pedestal breaker is off and then plug in the cord, once connected I turn on the breaker. Yes, I'm using the breaker as a switch but it's not mine and I don't have to replace it if it fails. I listen for the loud "thunk" which means the PI HW50C surge suppressor has checked everything and deemed it safe to power up the rig. If no "thunk" I check the panel for the problem code and get it corrected.

Just my way of doing things. FWIW

 

[swburbguy]

Also the plug should be hard to push in if the park pedestal isn't weak

 

[wdk450]

The park's pedestal breaker should be OFF before connecting or disconnecting your shore power cord. This prevents arcs and receptacle/plug deterioration from the degraded copper prongs/sleeves connections due to arcing. There is no arcing with no load applied.
I personally also have my inside trailer main breakers off before plugging/unplugging the shore power cord to eliminate load induced arcs on the contacts of the main power relay on my Progressive HW-50C power protection system. The generator transfer relay should be normally closed to the shore power current path and therefore not be subject to contact arcing. When switching AC loads there has to be an arc somewhere, and I choose it to be at my inside mains circuit breakers. My logic in this is that the new circuit breaker is relatively available and accessible if it fails due to contact degradation, where the EMS relay is a mail ordered part that is located in the utility crawl space, and therefore hard to replace.

 

[TravelTiger]

Just to chime in here, we make sure the breaker at the pedestal is off, plug in the Marinco twist lock into the back of the rig, plug the other end of the shore cable that has the SurgeGuard already attached into the pedestal. Flip breaker on Pedestal. Once the Surgeguard tests the connection (2min or so), it clicks on and lights the front accordingly. We verify that, then we go inside to verify AC power (the microwave time dots showing on screen.) We usually then crank up the ACs while we unhitch and set up outside.

 

[sjandbj]

It sounds like the connector from the rig to the surge guard does not get removed when you travel from spot to spot. If that is the case the contacts can get dirty since there is not the sliding of the plug against the receptacle. This may have help lead to the problem along with the hot weather causing a greater load. Just my observation from reading all the post.

Regards,
Steve

 

[brianharrison]

Hi, Brian! That's the way I've been doing it -- testing first then connecting everything. Was wondering (again, based on comments in Erika's thread) whether I'd been doing it wrong all these years. LOL

Paranoid, I guess, but it only takes one mistake to have a serious problem.

One last thing - you did not state the model of your surge protector - ie - if it also checks for high/low voltage, high/low frequency, open neutral, open ground. The Progressive Industries EMS-PT50C is the portable model that has all of these features. The smart surge model (no voltage/frequency protection) is a second choice - Model SSP-50. Other manufacturers also have similar units. I like the Progressive Industries product and after sales service/warrranty.

Brian

 

[Gaffer]

Never connect your trailer plug to a hot receptacle. There will always be some load that is not turned off. This load will cause a spark on upon connection that you may or may not see. Every spark will contribute to reduced conductivity. Reduced conductivity equals resistance which means heat.

Initially posted this in a related thread where Erika had a bad experience with her 120 volt AC system that caused some damage. Didn't want to detract from that thread so I'll repost my question(s) here.

Some folks are saying that you should turn off the 50 amp breaker (at the park's box, I assume). Why?

I always plug the surge protector into the park's power box first just to test the circuit there. If the park's electrical system fails the surge protector's built-in test (via five lights on the protector), I don't plug it into the RV.

Then I unplug the surge protector from the park's power, connect the 50 amp cable to the surge protector, check to make sure all of the connections are tight, then, and only then, I connect to the park's AC power.

Connecting to the park's AC power takes only a split second.

Have I been doing this wrong?

 

[TravelTiger]

One last thing - you did not state the model of your surge protector - ie - if it also checks for high/low voltage, high/low frequency, open neutral, open ground. The Progressive Industries EMS-PT50C is the portable model that has all of these features. The smart surge model (no voltage/frequency protection) is a second choice - Model SSP-50. Other manufacturers also have similar units. I like the Progressive Industries product and after sales service/warrranty.

Brian

If this was directed at me, yes our unit did that. Saved us a number of times from low voltage and bad pedestals.

Have a PI unit coming to replace ours that cooked.

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[brianharrison]

Sorry Erika, I was asking TxCowboy but thanks for replying. I have been following your other thread with your power incident and was wondering the same thing about yours. I had a hot prong melt the 50 to 30 adapter (on the 30A male end) once when I was in a park that my EMS showed a voltage of 107 (low shut off). I attributed the high amperage/resistance at the prong partially due to low voltage.

Apologies to TxCowboy for hi-jacking his thread - back to the main show.

Brian