Discuss Split amperage into two circuit breakers in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net

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fhaider

Hi.
I am in holidays at the campsite Camping Olhao in Algarve, Portugal and I have in my caravan an air conditioner that consumes about 9 Amps (220V). Unfortunately the electricity sockets available here for the campers are protected with circuit breakers of 6 Amps (220V) and that cannot be changed to a higher amperage. In order to have my air conditioner working I did run two cables connected to a socket each and inside my caravan I did join the live wires together and the neutral wirtes together in order to split the 9 Amps I need into the two circuit breakers of 6 Amps each. With this operation I manage to use the air conditioner, but it does not split the amperage 4.5 Amps into each circuit breaker (half of 9 amps), I get 6 Amps in one circuit breaker and 3 Amps into another.
I would like to find out if there is any way that I can control the splitted amperage in order to get as closer as possible to 50% (4.5 Amps) into each circuit breaker, by doing so I will be able to use more electrical appliances at the same time.
Thanks in antecipation.
 

Murdoch

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Whosh, bang, call the fire brigade.

Not sure that you should be doing this if you want to remain in safety.
 

Marvo

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You're lucky both the supplies you combined were from the same phase otherwise you'd already be missing eyebrows. Stop what you're doing before you cause damage of a fire. You can't run a single appliance from two separate circuits and balance the current through each. The only way is to replace the circuit breaker with one of higher capacity and only if the wiring is sufficiently sized.
 

plugsandsparks

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You cannot control like that, the load follows the easiest path. BTW how do you known what current is going down each, is there a meter on the box ?

You had a lucky break though.

Happy camping
 
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fhaider

You cannot control like that, the load follows the easiest path. BTW how do you known what current is going down each, is there a meter on the box ?

You had a lucky break though.

Happy camping
First of all I made sure that the live wires I joined together was from the same phase, using a proper tester. Secondly I did protect with circuit breakers of 6 Amps on my caravan before the joining points to make sure that if something goes wrong the circuit breaker will cut off. I have used an clamp amp meter to check the amperage on each circuit.
I am certain that there is a theory that establishes how the amperage is splited, that is what I would like to know.
 

Strima

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Why did I waste my time doing courses, this electrical thing is easy, just join some cables together until it works... :thinking:
 

plugsandsparks

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First of all I made sure that the live wires I joined together was from the same phase, using a proper tester. Secondly I did protect with circuit breakers of 6 Amps on my caravan before the joining points to make sure that if something goes wrong the circuit breaker will cut off. I have used an clamp amp meter to check the amperage on each circuit.
I am certain that there is a theory that establishes how the amperage is splited, that is what I would like to know.
Well you're almost an electrician...:) the theory is ohms law.
Very simply, measure the voltage at each site socket if you can. Then measure the resistance of your two cable layout outs. Its easier with an earth loop impedance tester across line and neutral but i guess thats not readily to hand.
Anyway the voltage that is presented at the caravan down each leg will proportionately take the load depedning on the voltage variation. Your two cables may be different in overall impedance which is making one take more than the other or the two supplies from the camp site might be slightly different.
This may also change over time as others load up so overall a bit of a dynamic situation for you.
Google ohms law, complex numbers, impedance and S and Z transforms to get a complete picture
 

plugsandsparks

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Been on a few caravan sites with my camper over the years, campers can be a resourceful lot, the sites do really have to work hard to keep the electric on as everyone plugs in fires up the microwaves, charge up all the leisure batteries, get the TV going and nowadays the air-con.

I agree without knowing what protection is in place at this site the guy could well do himself an injury, but we have told him already and he has a proper tester, he's probably smart enough to know what is involved here.

The bit that worried me was him expecting the power to be balanced, its when it starts to oscillate i think would be the time to abandon ship.

Anyway he has been warned already, he's an adult, if he reads the theory he will at least appreciate that electricity can do more than just be ordered to go down a wire in an stable fashion.
 

Strima

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Didn't read the 'proper tester' bit, that's OK then, I use a 'proper tester' all the time...
 

HandySparks

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Question for the OP:
Are these sockets that you are taking your supply from RCD protected?
If so, are they both on the same RCD?

Thanks.
 

Rockingit

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I think what the OP may be reaching for here is Kirchoffs Law.

But please, please, obey the first law of common sense before you do anything else. It's unlikely your holiday insurance would fly your corpse home when they discover the manner of your demise.
 
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F

fhaider

Question for the OP:
Are these sockets that you are taking your supply from RCD protected?
If so, are they both on the same RCD?

Thanks.
Yes, these socket are RCD protected and from ther same RCD.
 
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