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Old 01-02-2015, 10:52 AM   #21
Irlpguy
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Quote:
quote:Originally posted by trlrboy

I'm not looking to change anything. I was planning to run my fireplace (1500W heater) and a separate heater, also 1500W. I just wanted to know if I plug the second heater into a plug in the same area as the fireplace... will I blow a circuit?
If you plug into the same circuit that supplies voltage to the fireplace then you will for sure throw the breaker. 20amp breakers are the maximum used in the Montana for the 120V lines, two 1500 watt heaters would exceed that 20amps and would much more than exceed the circuit if the fireplace happened to be on a 15amp circuit and you plugged into an outlet on that same circuit.

As Bingo said the worst you could do is trip a breaker, if that happens move the heater to another circuit across the room or whatever.

There seems to be fairly differing ways in which the wise men at Keystone wired the circuits with respect to balancing the load.

You do have 50 amps on each of the two circuits supplying 120V, that was your original question, the message took some wrong turns but was well explained by BB_TX.

Hope we don't further confuse the issue and your questions have been addressed.

Keep the home fires burning and keep warm.




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Old 01-02-2015, 11:18 AM   #22
Phil P
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Hi Ozz

This is the way I find the easiest to see how the 220 /240 v service works.



This is the standard 220 / 240V service provided by the utility companies in the US.

The wires marked 120V are L1 and L2. The natural is the center tap.

The + and – marks are there to help with the theory when it is taught in a class room. AC doesn’t have any fixed + and - they alternate from one side to the other.

You will note the 240V making doesn’t have a line to the center (neutral) tap.

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Old 01-02-2015, 11:42 AM   #23
Phil P
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For all of you!!!

My advice is similar to Iripguy.

Your power cord supplied with the trailer and the power distribution center in the trailer will handle all of this theory.

As long as you add appliances to the existing receptacles in your trailer the power center will prevent any damage.

Like BB TX says the worst that will happen is you trip a breaker in the power center.

Where the dealers and repair facilities find massive damage caused by improper wiring or high voltage is when the owner unplugs his washer drier in the garage and sees what looks like the 30 amp receptacle in a RV Park. The dog bone used to connect to a 30 amp service in the RV Park can be forced into this washer drier 240V receptacle. This causes massive failures of electronic equipment in the trailer.

If you are going to provide power for your trailer at your home or some location that wasn’t wired for an RV then have an electrician install a proper receptacle so you can use the cord that came with the trailer.

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Old 01-02-2015, 12:53 PM   #24
twindman
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This is off topic, but how do 30 amp cords work? Does the same input go to both sides of the panel? i.e. each of the 2 sides for 50 amp? Since there is one less line, I was just curious.
Thanks.
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Old 01-02-2015, 01:49 PM   #25
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I take it you're referenceing a 30 amp to 50 amp Dog Bone adapter. In that case, both L1 and L2 are connected to the single Hot lead from the 30 amp plug. So in that case you are limited to a max of 30, thus you generally can't run both ACs, provided you have two or you can't run the coffee maker, microwave, toaster, and electric frying pan all at the same time. You have to do manual Power Management.
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Old 01-02-2015, 01:55 PM   #26
Irlpguy
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Quote:
quote:Originally posted by twindman

This is off topic, but how do 30 amp cords work? Does the same input go to both sides of the panel? i.e. each of the 2 sides for 50 amp? Since there is one less line, I was just curious.
Thanks.
You will notice that 30amp amp cables use only 3 wires, L1(hot), neutral and ground.
If you were able to inspect the inside of the pigtail used to run a 50amp wired RV from a 30amp service you would see that the single hot wire goes to both the hot wires in the 50amp cable, this is done internally in the short pigtail.

The single hot wire must be split in this fashion in order to feed both sides of the electrical panel on a 50amp service.

In this configuration you only have 120V to the RV electrical panel, whereas in the 50amp service you have two hot wires L1 & L2 each with 120V, measuring the voltage across L1 & L2 shows 240V.
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Old 01-27-2015, 04:09 AM   #27
Slink
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Quote:
quote:Originally posted by trlrboy

I'm not looking to change anything. I was planning to run my fireplace (1500W heater) and a separate heater, also 1500W. I just wanted to know if I plug the second heater into a plug in the same area as the fireplace... will I blow a circuit?
No, I run mine all the time
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Old 01-27-2015, 04:14 AM   #28
Ozz
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Yes, that would overload it. The heaters really pull a lot of amps, you would have to plug the heater into another circuit nearby. If you have to run an extension cord to do the portable heater, try and buy a 12 ga. (heavy duty) extension cord. Then you should be Ok, unless you have a substantial load on that second circuit.
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Old 01-27-2015, 06:43 AM   #29
jamesva
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So what happens inside the electricial circuit when plug into 30 amp and run your ac. This is what set up at my house is 30 amp with 10 gauge wires.
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Old 01-27-2015, 07:58 AM   #30
Irlpguy
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quote:Originally posted by jamesva

So what happens inside the electricial circuit when plug into 30 amp and run your ac. This is what set up at my house is 30 amp with 10 gauge wires.
If you think of the 30 amps being divided to the two 50 amp circuits in your RV (this is what happens) then you have 30 amps on line #1 and its main breaker and 30 amps on line #2 and its main breaker, however combined you still only have 30 amps, therefore if you are using (ie) 20 amps on the circuit that is wired with the AC then you have only 10 amps remaining on that circuit or the other circuit. You only have 30 amps to work with, that total is combined between both circuits in the RV.

Now if you are running your AC and start your microwave which is most likely on a different circuit, you will exceed the capacity of the breaker supplying the 30 amps to the RV and it will trip. Any total current draw in the RV that exceeds the 30 amp supply breaker will cause it to trip.

Due to line loss your supply to the RV should be as short as possible and heavy enough to carry the 30 amps. I don't think 10 gauge wire is sufficiently heavy and would certainly cause the breaker to trip.

I have a progressive power system in my RV and have a fairly long supply line on my 30 amp line, the power monitor sees a considerable voltage drop when I try to use the AC and it trips the Progressive system. If I turn off the monitoring system I can run my AC but am running it at reduced voltage which in time could cause damage to the AC so I don't run it. If I am just running heaters then I don't worry about damage to them at reduced voltage and usually can run a 750 watt and a 1500 watt heater at the same time, as long as combined they do not exceed 30 amps.

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Old 01-27-2015, 08:34 AM   #31
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Quote:
quote:Originally posted by Irlpguy

Quote:
quote:Originally posted by jamesva

So what happens inside the electricial circuit when plug into 30 amp and run your ac. This is what set up at my house is 30 amp with 10 gauge wires.
If you think of the 30 amps being divided to the two 50 amp circuits in your RV (this is what happens) then you have 30 amps on line #1 and its main breaker and 30 amps on line #2 and its main breaker, however combined you still only have 30 amps, therefore if you are using (ie) 20 amps on the circuit that is wired with the AC then you have only 10 amps remaining on that circuit or the other circuit. You only have 30 amps to work with, that total is combined between both circuits in the RV.

Now if you are running your AC and start your microwave which is most likely on a different circuit, you will exceed the capacity of the breaker supplying the 30 amps to the RV and it will trip. Any total current draw in the RV that exceeds the 30 amp supply breaker will cause it to trip.

Due to line loss your supply to the RV should be as short as possible and heavy enough to carry the 30 amps. I don't think 10 gauge wire is sufficiently heavy and would certainly cause the breaker to trip.

I have a progressive power system in my RV and have a fairly long supply line on my 30 amp line, the power monitor sees a considerable voltage drop when I try to use the AC and it trips the Progressive system. If I turn off the monitoring system I can run my AC but am running it at reduced voltage which in time could cause damage to the AC so I don't run it. If I am just running heaters then I don't worry about damage to them at reduced voltage and usually can run a 750 watt and a 1500 watt heater at the same time, as long as combined they do not exceed 30 amps.

There's a very good possibility that the break will not trip in your scenario. A/C units hit maximum amps when starting, around 13 to 15 amps. After that, they cut back to somewhere around 7 to 8 amps (IIRC), so firing up the microwave will have no effect, unless you happen to hit right at the start up of the A/C, and even then, with just those two items running, you will probably be OK. If you have several other items running, like the fridge, TV, etc., then yes you could have problems. But it's unlikely just the A/C and micro will exceed the 30 amp breaker's limits.
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Old 01-27-2015, 11:33 AM   #32
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If your 2010 3400rl is wired the same as our 06, you will find that all the center area 'kitchen' outlets are on circuit 3. The outlet in the stairway to the bedroom, the outlet by the eating area on the big slide (inside and outside), the outlet at the end of the counter and even the vacuum outlet are all on that one circuit. Include the fridge too! The microwave has its own. Circuit 4 includes all the outlets in the TV area, the office, and the two on the back wall. Generally we run the heater on circuit 4, can watch TV (40" LCD, sat box and receiver) and use either the kettle or the toaster on circuit 3 without an issue. If we want the fireplace heat on, we move the portable heater to either the washer or dryer outlet (they are each one their own breaker), but cant use anything like the kettle, toaster, vacuum, or microwave at the same time. If we want one of those, we turn off one heat source. If we wake to a real cold morning, we can run the both heat sources, and the furnace, as long as the park source is 'good'. We have a Progressive EMS and it gets cranky if the park source is marginal.
As an aside, we live with 30 amps for 7 months of the yr, you just need a little awareness of what your electrical draw is to minimize trips out to the park service pole to reset the breaker, that only happens when its dark or rainy!
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