Truck camper install question.

JoeyJ55

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Hello everyone and thanks in advance!
Getting ready to install a 350 watt system on my truck camper. I don’t have an automatic transfer switch so hoping I can just power off the inverter when I connect to shore power or my inverter gen set or does it matter?
 

MisterSandals

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a 350 watt system
What is a 350 watt system?

I don’t have an automatic transfer switch so hoping I can just power off the inverter when I connect to shore power or my inverter gen set or does it matter?
Is your inverter output wired in parallel to the shore power wiring? That would be pretty dicy if that wiring is counting on the inverter being powered off. I'd say extreme fire hazard.
 

Bob B

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Hello everyone and thanks in advance!
Getting ready to install a 350 watt system on my truck camper. I don’t have an automatic transfer switch so hoping I can just power off the inverter when I connect to shore power or my inverter gen set or does it matter?
In my truck camper, I have to plug the campers main power cord into a 30 connector If I want to run off the generator ..... so, when I am just running off batteries / inverter, I do the same thing. I just plug into the inverter and turn off the converter.

Yeah, more hassle than automating it, but I don't switch back and forth very often. If I am setting up where I have shore power, it is just part of the set up process ... and part of the get ready to go process when I'm leaving. Just unplug from shore power and plug into inverter power and turn off the converter.

Oh .... and I have a setup and take down checklist on my phone ... kinda like an airplane take off list
I have done that ever since I forgot to swing out the jack brackets and damaged the fenders on my dually.
 

HRTKD

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An Automatic Transfer Switch is the safe way to go. Otherwise, if you can plug your shore power plug into the inverter, that helps to avoid having both AC sources connected to the main at the same time.

Where is the AC-DC converter in this? If it is active when the inverter is on, then you have a loop and that's no good.
 

JoeyJ55

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In my truck camper, I have to plug the campers main power cord into a 30 connector If I want to run off the generator ..... so, when I am just running off batteries / inverter, I do the same thing. I just plug into the inverter and turn off the converter.

Yeah, more hassle than automating it, but I don't switch back and forth very often. If I am setting up where I have shore power, it is just part of the set up process ... and part of the get ready to go process when I'm leaving. Just unplug from shore power and plug into inverter power and turn off the converter.

Oh .... and I have a setup and take down checklist on my phone ... kinda like an airplane take off list
I have done that ever since I forgot to swing out the jack brackets and damaged the fenders on my dually.
Thanks Bob, since posting this I came to the same thought. What I’ll do is just wire the output of the inverter to a 30 amp receptacle in the cable bay and just plug into the “solar” side most of the time. I boondock most of the time anyway and have off grid property, no microwave so really only need external power if I need to top off the batteries or run the AC. With solar added I should only need to run the generator for the AC which is rarely. I use a portable inverter generator and a Softstart on the AC so I have to pull the power cord out anyway so no extra work really. The softstart is awesome, btw.
 

JoeyJ55

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An Automatic Transfer Switch is the safe way to go. Otherwise, if you can plug your shore power plug into the inverter, that helps to avoid having both AC sources connected to the main at the same time.

Where is the AC-DC converter in this? If it is active when the inverter is on, then you have a loop and that's no good.
Thanks!
I assume you’re speaking about the onboard AC-DC converter? I don’t see where that would be a loop issue, am I missing something? It’s just powering the 12 volt items like normal. I do have some concerns regarding the charger portion of the converter and wasting solar generated power by duplicating the charge controller so looking at a manual disconnect for that. Most of the time the solar will more than cover charging the battery on it’s own going forward so even if connected to external power I’m probably better off with it not charging. These older converters don’t have the best charging profiles anyway. I live in Arizona so no shortage of sun.
 

Bob B

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Yeah .... don't forget about the converter. I just leave mine powered off by default .... but if changing over from shore power to inverter power ... gotta make sure that is off.

Oh just saw your new post. If you are plugging the inverter in using the shore power plug on your camper .... that would be creating a loop .... you would be powering the converter with inverter / battery power ... and then the converter would be trying to charge the batteries.
You don't want that going on.
 

chrisski

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plugging the inverter in using the shore power plug on your camper .... that would be creating a loop .... you would be powering the converter with inverter / battery power ... and then the converter would be trying to charge the batteries.
You don't want that going on.
I left my converter circuit breaker tripped the first time I plugged it in. I was drawing an extra 700 watts to 1000 watts as my batteries were trying to charge themselves. I heard clicking by the batteries which I think was the self resetting breakers.

Left going a long time, that probably is not good at all.

There's three circuit breakers I trip before I plug in to the side, the converter, the front Air Conditioner and the Rear Air-conditioner. The air conditioners are 20 amps and my inverter only provides 15 amps.

Now, when I have shore power, I still leave my converter off. I let the solar panels charge back the 20 ah - 40 ah DC I will use overnight from leaving the 12 volt LED lights on. The system easily handles that. I don't really have a good answer on if my 15 amp converter made for my 92 ah original battery would recharge my 458 ah system that can be charged up to 60 amps. I know the SCC is a better charging voltage at 14.5 than my RV converter at 13.6.
 

JoeyJ55

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Yeah .... don't forget about the converter. I just leave mine powered off by default .... but if changing over from shore power to inverter power ... gotta make sure that is off.

Oh just saw your new post. If you are plugging the inverter in using the shore power plug on your camper .... that would be creating a loop .... you would be powering the converter with inverter / battery power ... and then the converter would be trying to charge the batteries.
You don't want that going on.
Unfortunately, I don’t have a way of turning off the charger side of the converter unless there’s something behind the “curtain” that I’m not aware of so I was just going to wire in a disconnect on the charger feed to the battery. It located n a pretty cramped area so I need to dig into that a little deeper.
 

chrisski

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Unfortunately, I don’t have a way of turning off the charger side of the converter unless there’s something behind the “curtain” that I’m not aware of so I was just going to wire in a disconnect on the charger feed to the battery. It located n a pretty cramped area so I need to dig into that a little deeper.
Most RV converters have a 15 amp CB dedicated to that. Perhaps a trucker camper is smaller and the C/B is tied to more than just an converter.

Finding my converter was a pain in the but!! Found it hidden behind the circuit breaker panel.
 

Bob B

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Unfortunately, I don’t have a way of turning off the charger side of the converter unless there’s something behind the “curtain” that I’m not aware of so I was just going to wire in a disconnect on the charger feed to the battery. It located n a pretty cramped area so I need to dig into that a little deeper.

There is probably a breaker in the electrical panel for the inverter. If there isn't .... that would be unusual .... and you would have to install one or re-think your plan.

Many times, you can get a electrical drawing for your camper .... what camper do you have?
 

chrisski

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There is probably a breaker in the electrical panel for the inverter. If there isn't .... that would be unusual .... and you would have to install one or re-think your plan.
I have at least three electronic panels in my trailer. I have a Circuit Breaker box by the door; a distribution panel in the pass through RV storage (I know very little what this does); and my leveling jacks have there own box with a hole lot of fuses. I'm sure once the OP digs, he'll find stuff like this, and there's probably a box or two I have not found yet.
 

JoeyJ55

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I left my converter circuit breaker tripped the first time I plugged it in. I was drawing an extra 700 watts to 1000 watts as my batteries were trying to charge themselves. I heard clicking by the batteries which I think was the self resetting breakers.

Left going a long time, that probably is not good at all.

There's three circuit breakers I trip before I plug in to the side, the converter, the front Air Conditioner and the Rear Air-conditioner. The air conditioners are 20 amps and my inverter only provides 15 amps.

Now, when I have shore power, I still leave my converter off. I let the solar panels charge back the 20 ah - 40 ah DC I will use overnight from leaving the 12 volt LED lights on. The system easily handles that. I don't really have a good answer on if my 15 amp converter made for my 92 ah original battery would recharge my 458 ah system that can be charged up to 60 amps. I know the SCC is a better charging voltage at 14.5 than my RV converter at 13.6.
Unfortunately, my little panel only has 3 breakers, 30 amp main, 20 amp AC and a shared 15 amp for the fridge, converter and 2 AC outlets so I have go another route so I can run my fridge on AC rather than propane. I really only use my AC outlets for charging USB devices and device batteries so I could cover that with 12 volts if I had to or use the outlets on my Samlex inverter with an extension cord if I had to, lol. But I would rather save the propane. More than likely I’ll just disconnect the converter completely and just rely on solar for charging the battery.
My 60 amp MPPT charge controller should be more than capable. Bypassing the converter charger would also allow me to install one of my Valence batteries which would more than double my amp hours. Currently just running a lead acid. Even so running the heat through the night last winter in 20-30 degree weather never dropped me below 50% by morning.
 

12VoltInstalls

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my little panel only has 3 breakers, 30 amp main, 20 amp AC and a shared 15 amp for the fridge, converter and 2 AC outlets so I have go another route so I can run my fridge on AC rather than propane.
Do you have one more empty slot in the breaker box?

The converter is either joined in the breaker box or in an outlet or junction box. You will find it because codes require junction boxes to not be permanently ’buried.’

If you can add a breaker, and the converter feed is not joined in the breaker panel, find the feed point for the converter and disconnect it at the junction and at the converter. It should be a dead line, now. Then run a fresh home-run from the new, 4th breaker to the converter. Likewise, if it joins in breaker box just put it on the new breaker.

Without a transfer switch, the inverter-as-shore-power pretty much guarantees you can’t loop or “back-feed the grid” from your camper- because it can’t!

The AC is your only real need to have ‘real’ shorepower because I would sell that propane/120 fridge and put in an electric 120V model that will run at 60 or 80 watts. Then I would provide a separate AC-only “shorepower” cord for the AC as you can plug that cord into the gen when needed (you’re sorta doing that already).
You’ll probably get enough moula for that dual-fuel fridge to buy the 120V fridge, a couple hundred watts more panel, and have money left over. And be grid-free for 20/30 years.

Just some thoughts for food. Or vis versa…
 

JoeyJ55

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Aug 20, 2020
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Thanks for the input.
No only 3 breaker slots, no room for expansion. My truck camper is a 2002 so the fridge is getting older but I like having the backup of AC and propane. I have 2 20lbs tanks on board so never away long enough to run low on propane. Biggest downside is only room for one battery without moving them to the other side on the camper and in the storage area under one of the dinette seats. I believe I’ll be fine with one Valence as my power requirements are pretty low. LED lighting and 12 volt/AC TV with a built in lithium battery for 4 hours of use helps. Refer and furnace in winter are the only big items. That and I’m usually out exploring all day so really just night time consumption.
Going to add a dc to dc charger for alternator charging down the road so should have all my bases covered. Coating the roof on the camper this week and then starting the install. I’ll post my results.
My 5th wheel will be the big project up next, lol.
 
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