RV/Camper power converter question.

[KitchenKitten99]

Hopefully someone can help me out here.

Remodeling the inside of my horse trailer weekender area. Upgraded the power receptacle to a 30 amp (previous owner only had a 15amp installed with no ground!). I intended to purchase the 30 amp power converter but accidentally purchased the 40 amp instead not realizing I clicked the wrong model. I plan on running mostly on battery power but obviously if power is available, I will use it.

Is this 40 amp version ok to install/use or do I have to go with the 30 amp?

The model that I purchased: https://wfcoelectronics.com/product/wf-8740-40-amp/

The description of the unit makes it sound like it will be fine but as I am new to all this, I am looking for reassurance.

Thanks in advance!!

[icansayit]

I believe Gunny is the DP Resident Electrician. GOOD LUCK.

[Evmetro]

That unit shows 40 amps on the DC output side, which is not the same as the input side. It sounds like your shore power wiring and inlet were recently upgraded to 30 amps and I'm guessing that it is 110 volts ac like your house is.

Trailer shorepower input: 30 amps x 110 volts = 3300 watts
WF 8740 converter DC output: 40 amps x 13.6 volts = 544 watts

It sounds like you have plenty of shorepower available to run that equipment.

[KitchenKitten99]

That unit shows 40 amps on the DC output side, which is not the same as the input side. It sounds like your shore power wiring and inlet were recently upgraded to 30 amps and I'm guessing that it is 110 volts ac like your house is.

Trailer shorepower input: 30 amps x 110 volts = 3300 watts
WF 8740 converter DC output: 40 amps x 13.6 volts = 544 watts

It sounds like you have plenty of shorepower available to run that equipment.

Ok so from what I understand from what you wrote, the plug-in "shore power" Amp number (on my receptacle) is not the same as the Amp number on the unit (in this case, the 40), which is actually the output of DC power from the (soon to be installed) battery/batteries? When I was picking up a couple other parts at CampingWorld (one was the 30amp receptacle), I asked the parts guy what I would need to connect it to and what I would need to use the plug or the batteries I planned to purchase, and he showed me the converter I linked, except it was the next model # that which was the 30amp. Probably why I thought they had to 'match'.

My whole plan is to be able run a small AC-powered mini fridge, small .5 amp water pump for the sink, and have enough "shorepower" left over to use a phone charger and a portable convection burner and maybe a small fan without overloading the whole thing. Also possibly charge my laptop. My interior lights are already running off the same main battery that powers the electric jack and won't be connected to the converter because I want to keep them completely separate. They're LED anyway and with my sky-light, will rarely be used.

Thank you for your help in this...I am just trying to understand all this and do it right the first time - and not set my trailer on fire. Google and YouTube are helpful but only if you know the right terms to use for searching and I often don't know them right away. This is my first time dealing with any kind of portable power system that is more complicated than just rewiring a stock or flatbed trailer and upgrading the wire harness, lights, etc, which I have done.

[Gunny]

Ok so from what I understand from what you wrote, the plug-in "shore power" Amp number (on my receptacle) is not the same as the Amp number on the unit (in this case, the 40), which is actually the output of DC power from the (soon to be installed) battery/batteries? When I was picking up a couple other parts at CampingWorld (one was the 30amp receptacle), I asked the parts guy what I would need to connect it to and what I would need to use the plug or the batteries I planned to purchase, and he showed me the converter I linked, except it was the next model # that which was the 30amp. Probably why I thought they had to 'match'.

My whole plan is to be able run a small AC-powered mini fridge, small .5 amp water pump for the sink, and have enough "shorepower" left over to use a phone charger and a portable convection burner and maybe a small fan without overloading the whole thing. Also possibly charge my laptop. My interior lights are already running off the same main battery that powers the electric jack and won't be connected to the converter because I want to keep them completely separate. They're LED anyway and with my sky-light, will rarely be used.

Thank you for your help in this...I am just trying to understand all this and do it right the first time - and not set my trailer on fire. Google and YouTube are helpful but only if you know the right terms to use for searching and I often don't know them right away. This is my first time dealing with any kind of portable power system that is more complicated than just rewiring a stock or flatbed trailer and upgrading the wire harness, lights, etc, which I have done.

Each piece of equipment should have a listing that tells you how many amps it draws. Add them up. If they exceed 80% of 40@ (which I don't think they do), you'll need to go with a 60@.

[KitchenKitten99]

Each piece of equipment should have a listing that tells you how many amps it draws. Add them up. If they exceed 80% of 40@ (which I don't think they do), you'll need to go with a 60@.

Thank you! This was VERY helpful and oddly enough no info I have read has actually said to do this.

[Gunny]

That unit shows 40 amps on the DC output side, which is not the same as the input side. It sounds like your shore power wiring and inlet were recently upgraded to 30 amps and I'm guessing that it is 110 volts ac like your house is.

Trailer shorepower input: 30 amps x 110 volts = 3300 watts
WF 8740 converter DC output: 40 amps x 13.6 volts = 544 watts

It sounds like you have plenty of shorepower available to run that equipment.

My question would be did this 30@ upgrade consist of popping in a 30@ breaker. Have to run minimum #10 AWG from it to any outlet. The receptacle itself would have to be upgraded to handle 30@. Cheesy house receptacles handle 15 or 20. Under-size wiring and/or receptacles are a fire hazard.

Not to mention most homes are built on the cheap. I'd calculate my panel load so my house lights don't dim when it's charging. Electric companies don't leave much room for addition on homes. One reason I'm glad I worked only commercial. I've done enough service calls to see some really weird stuff.

As far as the equipment itself goes, if it's AC plug-in to charge, it should be fine, as you stated. 11-120 is converted by the internal transformer and is stored in the battery as 220.

I would be very concerned about the ground and was it mine, I would have 2 -- the internal that comes with the unit and I would run a separate external to the frame.

[Evmetro]

My question would be did this 30@ upgrade consist of popping in a 30@ breaker. Have to run minimum #10 AWG from it to any outlet. The receptacle itself would have to be upgraded to handle 30@. Cheesy house receptacles handle 15 or 20. Under-size wiring and/or receptacles are a fire hazard.

Not to mention most homes are built on the cheap. I'd calculate my panel load so my house lights don't dim when it's charging. Electric companies don't leave much room for addition on homes. One reason I'm glad I worked only commercial. I've done enough service calls to see some really weird stuff.

As far as the equipment itself goes, if it's AC plug-in to charge, it should be fine, as you stated. 11-120 is converted by the internal transformer and is stored in the battery as 220.

I would be very concerned about the ground and was it mine, I would have 2 -- the internal that comes with the unit and I would run a separate external to the frame.

Indeed, there may be other wiring problems between the new 30 amp shorepower "inlet" and the device in question. To safely run that equipment, the trailer would need to have the appropriate size wire in whatever branch circuit it is in, if there are ever branch circuits at all, and of course proper grounding. I like your grounding to frame recommendation as well.