120v charging for 48v system?

jameshowison

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Hopefully a simple question, I'm just getting started :)

I'm considering a 48v system for an RV. Primary need for 48v is to run the Hotspot heat-pump (which runs directly off 48v).

I would also like to be able to charge batteries from 120v connections (regular 15amp plugs, and very often 30amp 120v connections via the TT-30 connector), we almost never stay at 50amp 240 sites.

I'm looking at the all-in-one 48v boxes from MPP, Growatt, and Victron. Often they seem to specify, for their chargers, AC input above 120v. e.g., "Input voltage range: 187-265 VAC" Does that mean that they can't charge from 120v sources at all?

Is it possible to use these all-in-one 48v boxes with 120v AC connections for charging? If not then what other route to a 48v RV system that does permit 120v charging?
 

jasonhc73

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MPP-Solar LV5048 or LV6048. The LV5048 is a couple of models older but works great.

These are split phases, 120/120 for 240. Yes, any RV 3 or 4 wire will work, as long as it's a 240 connector. If a 3 wire connector, just have to jumper the ground and neutral, and it will work fine.

You can run these with just one leg (120V), putting the same leg on both inputs works. Page 7 of the users manual shows the setup.

 

cinergi

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Victron makes 230v and 120v versions of their inverters. If you pick a 120v inverter/charger, it will both produce 120v and charge from 120v. A more complex configuration with 2 of their 120v inverters would allow you to charge from either 120 or 240 while producing 240 (split phase) output at all times.
 

jameshowison

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Thanks all. Yes, I see the p7 location in the MPP manual (also see that the "Nominal Input Voltage" is "110/120Vac(L-N or L1-N-L2)". Also now see the Growatt 48v 120v AC input, such as https://watts247.com/product/spf-3000tl-lvm-48p/

For Victron I see this one: https://www.victronenergy.com/upload/documents/Datasheet-MultiPlus-II-48V-3kVA-35-50-120V-EN.pdf

Does anyone know a way to do a faceted search (with filters) for Victron equipment? I find it maddening to click around their site ... I'd like to be able to say "all 48v" and "all 120v input" ...

Also with Victron and 120v you get the charger-inverter but you need a separate MPPT for solar input, right? Is it only their "EasySolar" that has the MPPT built in (and that has no 120v version).
 

jameshowison

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MPP-Solar LV5048 or LV6048. The LV5048 is a couple of models older but works great.

These are split phases, 120/120 for 240. Yes, any RV 3 or 4 wire will work, as long as it's a 240 connector. If a 3 wire connector, just have to jumper the ground and neutral, and it will work fine.

You can run these with just one leg (120V), putting the same leg on both inputs works. Page 7 of the users manual shows the setup.


Thanks. I'm wondering why you say "it has to be a 240 connector" (which I think you mean either the 3 or 4 wire (e.g., Nema 14-50 or 6-50, or (guessing) 6-15 or 6-20 which are lower current 240).

I'm hoping to connect a TT-30 RV plug (30 amp 120v) ... and if I had to plug into a 14-50, I'd use a converter to a TT-30 which I'm pretty sure just passes through one leg of the 240, so one ends up with 120v up to 50amp. I'm guessing you can tell the charger never to draw more than 30amp (or actually probably 24 amp)?

Does anyone have photos of a 120v only input to the MPP-Solar LV5048 or LV6048? Do you wire the 120v L into L1, and then a short jumper from L1 to L2, or do you do it outside the MPP (e.g., in a junction box, connecting L to short wires to go to L1 and L2)?
 

cinergi

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For Victron I see this one: https://www.victronenergy.com/upload/documents/Datasheet-MultiPlus-II-48V-3kVA-35-50-120V-EN.pdf

Does anyone know a way to do a faceted search (with filters) for Victron equipment? I find it maddening to click around their site ... I'd like to be able to say "all 48v" and "all 120v input" ...

Also with Victron and 120v you get the charger-inverter but you need a separate MPPT for solar input, right? Is it only their "EasySolar" that has the MPPT built in (and that has no 120v version).

For 48v you're limited to that MP2 and the Quattro's basically. And yes you need a separate MPPT SCC for those.
 

jasonhc73

Cat herder, and dog toy tosser.
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Thanks. I'm wondering why you say "it has to be a 240 connector" (which I think you mean either the 3 or 4 wire (e.g., Nema 14-50 or 6-50, or (guessing) 6-15 or 6-20 which are lower current 240).

I'm hoping to connect a TT-30 RV plug (30 amp 120v) ... and if I had to plug into a 14-50, I'd use a converter to a TT-30 which I'm pretty sure just passes through one leg of the 240, so one ends up with 120v up to 50amp. I'm guessing you can tell the charger never to draw more than 30amp (or actually probably 24 amp)?

Does anyone have photos of a 120v only input to the MPP-Solar LV5048 or LV6048? Do you wire the 120v L into L1, and then a short jumper from L1 to L2, or do you do it outside the MPP (e.g., in a junction box, connecting L to short wires to go to L1 and L2)?
On the LV6548 I have now, I can limit the AC charging as low as 2 amps, or intervals of 10. The LV5048 I used to have was 10 or higher, up to 60 in intervals of 10.

The LV6548 is not a split-phase inverter, it has to be paired with another LV6548 to get 240V.

How to put a single phase into the LV5048/LV6048:
 

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Short_Shot

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I'm looking at the all-in-one 48v boxes from MPP, Growatt, and Victron. Often they seem to specify, for their chargers, AC input above 120v. e.g., "Input voltage range: 187-265 VAC" Does that mean that they can't charge from 120v sources at all?

You're either looking at euro 230v units, OR that's "split phase" 230, which is what the 50a shore plugs actually are.

You need to find a 120v US version.

Like this one:
 
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