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15 amp service question

Back on 5/1/10, Michelle provided excellent advice on living with 30 amp service (What will not work on a 30 amp service).  However, my question is - given moderate weather than does not require AC during the day and only the furnace at night - how do the guidelines change when only 15 amp service is available (ie, such as when parking in a friend's driveway for a night or two  ::) )?

FYI, here are her insights from that post:

We lived on 30 Amp all last summer in Maine (5 months).  As a rule, we could run one of the following:

Aquahot on electric
Microwave/oven
One A/C (either A/C or heat pump operation)
Splendide W/D
My hair dryer
The espresso machine

As long as we only had 1 of the above units on, we were fine with the regular usage of computers, fridge, TV, etc.  You learn pretty quickly to "power manage" and it becomes second nature to turn one major appliance off before turning another on.
The selected media item is not currently available.Pat Hatfield
2000 U295 3600 #5666 WTFE (sold 1/7/20)
2014 Jeep Grand Cherokee
previously: 2003 U295 3610 #6228 (sold 5/29/14)
previously:  2009 Honda CRV (sold 6/9/14)

Re: 15 amp service question

Reply #1 –
Pat,

Assuming you have adequate voltage (not a given, as most 15 amp outlets are supplied by small-gauge wire) You can run one A/C IF NOTHING ELSE IS ON.  So, with everything else off (particularly the battery charger or inverter/charger), turn on the A/C while monitoring voltage when you turn it on.  Within 15 seconds, voltage should stabilize at 110 VAC or above.  108 VAC is the absolute lowest that will not harm the A/C.

The exception to the above is if the batteries are very near full charge, in which case the charger or inverter/charger can be left on, as its amp draw is low if not charging a discharged battery bank.  If you are marginal on voltage/amp draw but still want the battery charger on, you can set your inverter/charger to power share/power save which allows you to limit the amount of 120 VAC that it can use. 
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 15 amp service question

Reply #2 –
Thanks, Brett, for the great explanation (as always!).  However, in this instance, my assumption is that the AC will not be used at all... but what other considerations are there for living with 15amp for a day or two?  Thanks!
The selected media item is not currently available.Pat Hatfield
2000 U295 3600 #5666 WTFE (sold 1/7/20)
2014 Jeep Grand Cherokee
previously: 2003 U295 3610 #6228 (sold 5/29/14)
previously:  2009 Honda CRV (sold 6/9/14)

Re: 15 amp service question

Reply #3 –
As long as total amp draw is under about 13 amps continuous, you just make the decision on what to use/what to turn off.  And, you can change that any time you like.  As an example, if you want to use the microwave, you might turn off other loads.  Easiest to do at the 120 Breaker box (foot of the bed).

There two issues here-- one is total amps and the other is how low does voltage drop under higher loads (but still under the 15 amps that would trip the outlet breaker).
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 15 amp service question

Reply #4 –
Pat,
          The refer on electric draws about 3 amps continuously, you can run that on propane to save that capacity. I installed an auxiliary 110 input connector along with a dedicated outlet in the old trash compactor area. We can use that direct line for kitchen appliances (coffee maker, microwave, toaster oven etc) or an electric heater if it is cool. That auxiliary line can be plugged into a shore line that is not connected to the circuit where the primary line is plugged in.
Good luck,
Rick
 
Rick

Re: 15 amp service question

Reply #5 –
I bought our new to us 320 after not rv'ing for 17 years.  Untested 100k 15 year old coach.  Omg.  Well I am good.  We will see.  At a lowes I was looking at power cords and picked up a couple of small adapters.  Was going to dry camp in both mid west sister-in-laws driveways for several days at a time.  No hook ups.  No pedestal  power. Hmmmm

Bought a 10 gauge rigid 100' extension cord.  Both places turned out to have 75 feet to 110 volt outlets in out buildings.  Whew.  Actually worked.  Aqua hot on 110.  Bedroom and bathroom only.  Thermostat kept low.  Refer on gas.  Batteries basically full.  Inverter off.  Large 130 watt solar panel on roof. 

Careful power control.
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: 15 amp service question

Reply #6 –
I would have run the AH on diesel and the  fridge on electric or maybe on gas as well.  Depending on the other loads on the system. I do not think the other pump would put out that much and the fans are 12 volt from the converter.  That was working so I would put on all zones and run it on diesel. Will not run that much anyway if it is not really cold out.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: 15 amp service question

Reply #7 –
Quote from: John S –
I would have run the AH on diesel and the  fridge on electric or maybe on gas as well.  Depending on the other loads on the system. I do not think the other pump would put out that much and the fans are 12 volt from the converter.  That was working so I would put on all zones and run it on diesel. Will not run that much anyway if it is not really cold out.

The aqua hot igniter had failed. Forgot that part. Was Fair weather in mid may in the Midwest other than the rag weed around Omaha.  Killed my allergies.
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: 15 amp service question

Reply #8 –
You can trip a breaker two ways, one is exceed the rating and by heat, a 15 amp breaker will trip at 12 amp with a steady 12 amp load given enough time to heat the trip, and of course it will trip from overload. During my trip to Black Hills, I stoped at Murdo SD, the CG only had 30  amp, so I bite, the 30 amp breaker was so weak just the a/c would heat and trip the pedistal breaker from heat, (Very Hot), no other load than a/c and guess the inverter charger. The voltage was 108 volts, and it did not take me very long before I insisted on a refund and drove down the road to a KOA that was the normal everything.
My opinion is to forget a 15 amp circuit, your playing a game that will eventually cost you money due to low voltage, not to mention the aggrevation of non stop resetting a weak breaker,  Why not run the generator to charge the batteries and when you need a/c, microwave or other high amp loads, TV works great on the battery system.
FWIW
Dave M

Re: 15 amp service question

Reply #9 –
the more and more I read of all these power problems the more I am glad I have all the power we need thru solar. It is safe on batteries and as long as we have sun Yippee ^.^d
I am in the process of ordering more solar panels from AMSolar as they have some 100 watt ones that will fit nicely between my others. Will pick them up on way south at Christmas.
John h
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: 15 amp service question

Reply #10 –
I have a few 50 amp plugs at home a 30 amp and a 20 amp too.  15 amp is just to keep the batteries topped off.  I agree with Dave, if I only have 15 amps and need to run an AC I just turn on the genset.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: 15 amp service question

Reply #11 –
Like Dave said, sooner than later you will damage some expensive stuff. I have one place we stay that only has a 15A GFI all we run is the battery charger, and lights Tv, any other loads we start the generator.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: 15 amp service question

Reply #12 –
A trick to run where you have lw power is to get a portable battery charger and plug that in.  It will keep a charge on your house batteries and you just live off 12 volt and your inverter.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon
 

Re: 15 amp service question

Reply #13 –
How to survive on 15 amp 120VAC service!

Vancouver Island, where I live in the summer, has few campgrounds with more than 15 amp service.

This is quite complicated, took many hours of designing, involves several major changes. What I have done works very well and complies with all safety/electrical codes. These changes should not be attempted by anyone who does not have a clear understanding of what I have done and why.

Inverter subpanel was removed after breakers were moved to the main panel.

Auto A/C selector switches (Triple pole) in the closet and under the bed were replaced with manual A/C selector switches (Double pole) in the top of the main panel (one for "Red Hot" and one for "Black Hot").

The breakers in the main panel were rearranged and increased in number from eight (plus 3 in inverter panel) to fifteen.

The single neutral bar in the main panel was seperated into two neutral bars, one for "red" hot and one for "black" hot.

In the utility bay, two 30 amp twist lock receptacles (hot, neutral, grnd) were installed above the original 50 amp receptacle (red hot, black hot, neutral, grnd).

A #6 wire was run from the main panel to the utility bay to allow each hot (red and black) to have seperate neutral wiring (allows two "ground fault" 15amp or 30amp supplies to be used concurrently).

The Freedom 2500 watt inverter/converter was replaced with a 1800watt pure sign inverter and a 55 amp converter. This allows the inverter to run the microwave while the batteries are being charged by the converter.

Now I can power the "red hot" breakers with a 30amp extension cord while powering the "black hot" breakers with a second 30amp power cord. If only 15 amp is available, an adaptor is required. Often, I can use two 15 amp campground receptacles when adjacent campsites are empty. I can also run the microwave (or hand tools) from the inverter while the water heater and the converter are powered from 15amp shore power (DW thinks we have 30amp service). I can run entertainment systems for the evening with water heater off, then run water heater after going to bed.

I run the generator for air conditioning or the convection oven (once in the last year) because I have 850watts of solar panels on the roof.

PM or phone at 250-477-5680 for details. 
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada