Microwave and AC Trip Breaker - Dealer Says Normal?

[Tom48]

I think converting to 50 amp from 30, would be a big job. Very expensive and beyond the skill level of many so called RV techs. I have looked at our coach and I COULD DO IT, but WOULD NOT. Splitting some of he breakers off to a separate 20 amp cord is doable, but not worth doing for our needs.

[DrJMB]

Not true on mine. They replaced my microwave as it turned on by itself. It was in a recall. Never tripped breaker.


Sent from my iPhone using Forest River Forums

[oldtool2]

Originally Posted by JimOneil43

What is involved in converting a 30Amp system to 50Amp? And what is the cost?
Thanks

New cord, new plug, new converter and electric panel and new heavier wire between the plug and converter / panel. Everything else would be ok as long as you could split off the individual circuits at the panel. If they split the circuits in the wall or overhead you could have a major problem locating the wiring.

This could be done by a good electrician or a good RV tech but it would not be cheap to do! I don't think it would be worth it.

This is off the top of my head, may be more to do.

Jim

[DoctorT68]

Curious about this myself.

[bgilly]

The ease of converting from 30 amp to 50 amp is not terribly bad but the level of difficulty depends on the type of load center that you have. Most motorhomes have the WFCO WF-8930/50. This does not have the built-in converter. I have the WF-8930 in my coach which is the 30 amp rated load center. It is nearly identical to the WF-8950 which has the additional buss for the other half of the load center. I don't think you will be able to just buy the buss to change the 8930 to an 8950 (though the thought crossed my mind) but buying a 8950 and carcass either the current 8930 or the new 8950 to get the 50 amp of service. Then add the additional #10 conductor to the shore cord as well as replacing the shore cord to support the 50 amp.
Now with 2) 25 amp busses, the load would have to be shuffled around so that each bus is carrying some balance (A/C on one 25 amp buss and microwave and elec. WH on the other 25 amp). Not a project for the average laymen but do-able for someone that knows load centers and load distribution.

Now, similar is possible for the TT or other RV units that come with the built-in converter: WFCO WF-87-- series (30 amp load center) but would be quite expensive because again, you can't just by a buss to change the WF-87-- to a WF-99-- ( the 50 amp load center) so basically you would have to purchase a WF-99-- which includes the converter.
OR just upgrade to another camper

[Tom48]

ANOTHER PLUG FOR SOLAR. Just looked at our system again. AND for those fighting the 30 amp or Generator's ability to carry both the AC and the Micro without blowing something, many times your problem is probably that you have something else running. The power converter can use 30 amps if the batteries are low and the water heater can use as much as 10 or 11 amps. So the Microwave while air conditioning problem is solved for most of us, if the WH electric is turned off and like us, the converter is UNPLUGGED unless in a pinch we need it, as the solar keeps out batteries topped off daily. So the solar helps out even if you are on a hook up, by freeing up amperage demand to cure the A/C and microwave.

[wmtire]

Originally Posted by Tom48

The power converter can use 30 amps if the batteries are low and the water heater can use as much as 10 or 11 amps.

Tom, just to make sure you are not confusing AC amps and DC amps. The converter takes input of 120 volt AC and converts it to 12 volt DC output. The converters are rated like 45, 55, 65 etc, of amps....but this is DC output amps.........and not AC amps.

This may help:

RV Converters and Amp Draw - RV Information (RV Maintenance)

Also, most of the current Suburban electric water heater elements draw 12 amps on 120 volt AC....and the Atwoods are similar.

Watts = volts X amps
1440 watts = 120 volts X 12 amps or 1440 watts/120 volts = 12 amps.

[Tom48]

Originally Posted by wmtire

Tom, just to make sure you are not confusing AC amps and DC amps. The converter takes input of 120 volt AC and converts it to 12 volt DC output. The converters are rated like 45, 55, 65 etc, of amps....but this is DC output amps.........and not AC amps.

This may help:

RV Converters and Amp Draw - RV Information (RV Maintenance)

Also, most of the current Suburban electric water heater elements draw 12 amps on 120 volt AC....and the Atwoods are similar.

Watts = volts X amps
1440 watts = 120 volts X 12 amps or 1440 watts/120 volts = 12 amps.

Thank you. That seemed so wrong when I read it on the Progressive Dynamic site and I should have re-read it then. Their 30amp charger lists max IN RUSH amperage as 32 amps. That would only be about 4 to 6 amps 120 usage after allowing for internal loss and a bit more if the voltage is low. But if you have a bigger converter it would be more too.

So that leaves us with start up amperage on the A/C near 20 and the microwave at around 10 or 12 amps and so the WH at 10 or 11 amps or the converter at 4 or 5 amps either one or both and there goes the breaker.

If my memory serves me when voltage goes down amperage draw increases and that is why motor get hot on low voltage and burn up etc. So spring for the $15 plug in A/C volt meter and watch your line voltage in these often underbuilt/overloaded park systems or marginal generator systems.

SAME DIFFERENCE in the context, but then you for reminding me to reread my sources and proof read my work better. Thanks TOM

[oldtool2]

I would like to see a wiring diagram for a converter. I have a Parallax Power Supply model 7155. If I understand right it will supply 55 DC volts amperage, hence the "55". Yet the main DC fuses are 30 amp fuses? From what I have read it draws 30 amps for the converter to operate but it works as a tridkle charger charging at a 3 to 5 amp rate. I don't see a 110 volt AC breaker so how much 110 VAC amperage does it draw and where is the protection (breaker) for the converter itself? I see the 30 amp main 110 VAC breaker and individual breakers such as air, water hrater, and GFI receptacles
(2 of them) and micro wave. That takes up all 5 slots. I also don't see any fuses marked for the converter output.

Am I reading the panel wrong, are the two 30 amp 12 VDC fuses for the output of the converter? That would make sense, but if that is the case it is not a trickle charger as many here have stated. Still don't see any breaker for the AC supply though.

I know I am getting up in years and am becoming brain dead but even so I am missing something.

Jim

[aceinspp]

I can also run the Ac and Microwave. I have the refrig on gas and water heater also. Later RJd

[oldtool2]

Originally Posted by Tom48

Thank you. That seemed so wrong when I read it on the Progressive Dynamic site and I should have re-read it then. Their 30amp charger lists max IN RUSH amperage as 32 amps. That would only be about 4 to 6 amps 120 usage after allowing for internal loss and a bit more if the voltage is low. But if you have a bigger converter it would be more too.

So that leaves us with start up amperage on the A/C near 20 and the microwave at around 10 or 12 amps and so the WH at 10 or 11 amps or the converter at 4 or 5 amps either one or both and there goes the breaker.

If my memory serves me when voltage goes down amperage draw increases and that is why motor get hot on low voltage and burn up etc. So spring for the $15 plug in A/C volt meter and watch your line voltage in these often underbuilt/overloaded park systems or marginal generator systems.

SAME DIFFERENCE in the context, but then you for reminding me to reread my sources and proof read my work better. Thanks TOM

Tom,

You may know this but thought I would mention this for those that don't. As a general rule of thumb start up amperage is 2X the running (operating) amperage. Some things actually may run much higher but that is a good starting place. I would think most RV manufactures try to avoid items that do surge much higher than that because of the probllems they can cause.

Jim

[oldtool2]

Originally Posted by aceinspp

I can also run the Ac and Microwave. I have the refrig on gas and water heater also. Later RJd

How big is your generator? I have a 3000 watt and think that would really be pushing the limit. Especially if the AC compressor kicked in while the microwave was running.

Jim

[elind]

Have you considered that in a 50 amp RV service you have two 50 amp phases going into the fuse box for a total of 100 amp total output or 12,000 watts? There is 240v coming in the box but RVs only use 120v to function. If you look at the 50 amp cable you can see the wires are 6 gauge vs 10 gauge wires in a 30 amp cable. It's like the difference between a garden hose and a fire hose.
There is as much power in my 50 amp RV as my 100 amp home.

Some reading about 50 amp service.
Well, what is 50 amp service?

[Tom48]

OLD TOOL
I looked at the Parallax Power Supply model 7155 specs and best I can see it claims to have a MAX charging capacity of 55 amps. No MOST internal Charger/Converters are not just trickle chargers. Most push a high charge rate til the battery is at about 80%. Are they all different, yes a bit I am sure. Not and engineer so I do not know how they reconcile 55 charge and 30 amp internal fuses??? In their web sight they seem defensive about not being Smart Chargers and that suggests to me they may be one size fits all OEM minimum quality hardware. I like the mentality of Smart Chargers and have that on my solar so I do not worry about my factory one size fits all 30 amp charger/converter.

I am not sure how many units are wired. Mine is in a nice eye level box and many seem to be under the sink or under the night stand and places that my crappy knees and back do not volunteer to work. My controller plugs in to an outlet on the wall in its compartment 6 inches away and since I went solar, spends only enough time in use so I can assure that it still works in case I pull my solar when we sell. Many are hard wired and in the case of one other solar install I have worked with lately, it is the sole unit on one breaker and we turn that breaker off and let 400 watts of solar and a very expensive MPPT controller do the job.

[Tom48]

Originally Posted by oldtool2

How big is your generator? I have a 3000 watt and think that would really be pushing the limit. Especially if the AC compressor kicked in while the microwave was running.

Jim

I agree. WE have a 4000 watt Onan and keep it clean as above so it will run both but even then, I keep my eye on house voltage so it is not pulled down too low for too long and start overheating and burning things up.

[funfinder5]

Originally Posted by elind

...
There is as much power in my 50 amp RV as my 100 amp home.

Does your house only have one phase going to it ( 120 volts AC)? If so that is very rare here in North America.

[elind]

Originally Posted by funfinder5

Does your house only have one phase going to it ( 120 volts AC)? If so that is very rare here in North America.

My home has 240v, 100 amp service. I'll correct myself to say that at 240v X 100 amp is 24,000 watts of power or twice of my 50 amp RV.

30 amp RVs have single phase of 30 amp with 3,600 watts of power.
50 amp RVs have two phases of 50 amps with 12,000 watts of power.
My point is 30 to 50 amp upgrades in RVs greatly increases the available power to run things.

[Cypressloser]

DoctorT68, you could install a Volt/Amp meter in line right before the main cable enters the control panel, this way you can always monitor the load on your system and learn quickly how to balance power usage.
Amazon.com: DROK® Digital Current Voltage Multimeter AC 100-300V 100A Voltage Amperage Meter, AC Volt Amp Testing Gauge Power Monitor LCD Dual Display Voltage Measuring Current Sensing Resistors with Current Transformer CT: Home Improvement

Edit: The link above is only an example.

[oldtool2]

Originally Posted by Tom48

I agree. WE have a 4000 watt Onan and keep it clean as above so it will run both but even then, I keep my eye on house voltage so it is not pulled down too low for too long and start overheating and burning things up.

OK, with a 4000 watt generator I can see running an AC and microwave together might be OK..

My Honda EU3000is generator has a "30" amp plug rated at 23.4 amps. I figure my 13,500 btu AC unit draws about 12 running amps, 22 -24 start up amps (when the compressor kicks in). I think my microwave is an 800 watt unit so it would draw 9.5 - 10 running amps, start up amps is about the same. Hum, lets see, 24 + 10 = 34 amps. I don't think that is going to work to well. Even a 4000 watt generator, 4000 / 120 = 33.3 amps. Even that is very close if they are running together.

However because a microwave that we use in a trailer are very efficient. 800 / 900 watt MW's normally only draw 10 to 10.5 amps so a 4000 watt generator even though it is really pushing it might be able to do it. Now if you have a 15,000 btu AC unit all bets are off!

As you can see I really doubt if my 3000 watt generator would handle both on start up. I will try it someday but expect to have to reset the generators breaker!

Jim

[oldtool2]

Originally Posted by Tom48

OLD TOOL
I looked at the Parallax Power Supply model 7155 specs and best I can see it claims to have a MAX charging capacity of 55 amps. No MOST internal Charger/Converters are not just trickle chargers. Most push a high charge rate til the battery is at about 80%. Are they all different, yes a bit I am sure. Not and engineer so I do not know how they reconcile 55 charge and 30 amp internal fuses??? In their web sight they seem defensive about not being Smart Chargers and that suggests to me they may be one size fits all OEM minimum quality hardware. I like the mentality of Smart Chargers and have that on my solar so I do not worry about my factory one size fits all 30 amp charger/converter.

I am not sure how many units are wired. Mine is in a nice eye level box and many seem to be under the sink or under the night stand and places that my crappy knees and back do not volunteer to work. My controller plugs in to an outlet on the wall in its compartment 6 inches away and since I went solar, spends only enough time in use so I can assure that it still works in case I pull my solar when we sell. Many are hard wired and in the case of one other solar install I have worked with lately, it is the sole unit on one breaker and we turn that breaker off and let 400 watts of solar and a very expensive MPPT controller do the job.

If I add up the fuses in my converter I get 120 amps. More than twice the 55 amp rating of the converter. That is not taking in consideration the 30 amp 12 volt converter (charger) or the 110 VAC load. I am sure the 12 VDC fuses are rated high but even so this makes no sense to me. Going to send them an e-mail and will post here what they tell me.

Jim
This is what I wrote to them. Hopefully I will get the answers needed.


"I have a few questions about the 77155 power converter.
1. How many amps does the 110 VAC charger draw?
2. Is the charger protected by a breaker or fuse, and if so where is it located?
3. How many amps is the output of the 12 VDC charger?
4. Is the charging output protected by the 30 amp fuses located at the top of the 12 VDC section of the panel?
I do see an inline 30 amp fuse about a foot from the battery and assume it is to protect the charger, correct?
I would greatly appreciate answers to these question and any other info you think might come in handy.
Thank you."