Victron MultiPlus II 12/3000/120-50 2x120V

jeffathompson

New Member
Joined
Aug 19, 2021
Messages
2
So this is not really a solar question, but more of an install question. Yes if this new Victron does what it is supposed to do, I will add solar. Maybe on this rig or I may be upgrading to a larger rig to fulltime in. Right now I just want to make sure I get this inverter/charger installed correctly as not to damage any other systems or light the thing on fire. I'm using 3 120ah flooded lead acid batteries. Kinda just want someone who has done a similar install to check my brain and see if I am putting things in the right order.
Ok, trying to get a grasp on this. It finally showed up just as I was leaving for a 2 week trip in the car. So the boxes are in the garage unopened.

I want to see if I have a grasp on the changes I'm making and check my thought patterns.

2006 Winnebago Journey 39k. It came factory, at 50 amp and a 7500 watt generator. It also has a Dimensions 2000 watt inverter/charger that has failed. (charge still works but no invert)

On the old setup, the shore power cord and generator wiring go to the ATS which is shore power priority. Then the 2 120 volt lines go into the main distribution panel that has a dual 50 amp breaker. It also has a 30 amp breaker marked "inverter" that feeds an sub panel that is just outlets and the refrigerator. If I trip the 30 amp inverter in the main panel off, the charger quits and everything on the sub panel quits. So I am assuming that it feeds the 120 to the charger and accepts the 120 from the inverter (when it worked)

If the inverter senses any shore power, even 15 amps it just over rides and stands by. Disconnect shore power, the inverter would start. It had one 120 output that ran over to line 1 in the ATS, meaning only 1/2 (30 AMp side)

The new inverter Victron MultiPlus II 12/3000/120-50 2x120V is a pass through and has 2 120 volt legs, meaning in theory, it will power everything in the RV. Also, if I am on 30 amp, and draw more than that, the inverter will add watts to make up the difference (assuming the batteries are up.

So where I am a little perplexed is the new install. I am thinking that I leave the shore power and generator wired where it is, take the output from the ATS and run that to the input of the passthrough inverter. The output of the pass through goes where the old output from the ATS, directly to the distribution panel. 12v Gets hooked up just like it is now. Positive and negative into the Victron MultiPlus II 12/3000/120-50 2x120V and then just eliminate the wire that came out to power the old inverter charger. (don't need 120 to it anymore as it is a pass through)
It also has an Intellic PMS. Which must be powered by the 30 amp breaker in the main panel. I spend a lot of time on 30 amp, so I don't want to loose the EMS but want to make sure the pass through inverter adds the watts I need. It normally would be short duration, but I can't tell you how many times I had to reset the parks breaker due to trying to get just a little too much out of it.

I'm thinking doing it this way the main panel will always think it has shore power or generator, even if only on the inverter. The inverter should pass 120 to both legs as long as I don't exceed it's limits.

As I say, it's still in the box in the garage, but my brain has been working on how to set this up. Maybe instructions will be very clear, but I've never counted on that.

Am I on the right track
__________________
2006 Winnebago Journey
39K
Cat C7
 

InMyImage

Solar Enthusiast
Joined
Nov 17, 2020
Messages
146
My 2018 Jayco North Point 5th wheel is also 50amps and my new Victron is sitting in my house waiting on install after we get our trailer back from a repair shop (hopefully by the end of September).

We also have an existing inverter because we have a residential fridge.

Like you we are frequently on 30amp shore power and can actually manage both AC’s without tripping the circuit breaker unless my wife forgets to turn one off before using her hair dryer, instapot, etc. So we are really looking forward to power boost functionality.

In my case I’m still researching but planning to do something along these lines, note I’m using a 2p4s Lithium battery bank but that shouldn’t change anything other than the charge settings. I do not currently have a generator but note that the Victron has a generator power input.
  • Disconnect the power converter with charge wizard and hopefully sell it.
  • Route shore power directly to the Victron.
  • Route power from the Victron directly to the panel.
Our existing inverter works fine so I’m also hoping to:
  • Separate the single current inverted circuit to a new separate small panel.
  • Route power from the Victron’s non-inverted output to the existing inverter.
  • Route power from the existing inverter to the separated panel.
If power isn’t available that should lower the power demand on the Victron from the refrigerator and and handful of existing inverted outlets allowing the Victron to only deal with power intensive demands like AC’s, small kitchen appliances like the microwave, instapot, etc. and all remaining outlets.
 

DIDDLYV

Solar Enthusiast
Joined
Mar 1, 2021
Messages
91
My image The AC 2 circuit on the Victron only works when there is shore power and does not have "Power Boost" or what ever is on the AC1 circuit to add additional inverter power to make up for lack of current when driveway surfing or running small capacity generator. Not sure why one would want the current draw of running 2 inverters simultaneously if the Multi Plus II has sufficient wattage to handle all the loads. But it may well be a great idea if you have either sufficient battery amp hrs, or sufficient solar to keep the batteries at a reasonable level of charge when running everything.

Jeffa I do not currently have an inverter so I will remove the current converter. Take the shore power wiring from the distribution panel 50 amp breaker and take into a junction box. Run new wires from that junction to the Multi Plus then run wires from the Multi Plus back to the distribution panel 50 AMP breaker. Depending on where I mount the Multiplus this wire run should be 8 to 12 feet. I may or may not put a breaker or cut off switch near the Multi Plus. My thoughts were if I wanted to disconnect shore power from the Multi Plus I could turn off the power pole breaker or just unplug the shore power cord from the box. I plan on mounting the Multiplus very close < 2 feet from the batteries. I did find it interesting the documentation from Victron has the multiplus II connected to the batteries with 2 1/0 cables hooked to the 12 volt positive lugs and 2 1/0 cables hooked to the 12 volt negative lugs. Prior to reading the documentation I had considered running a single 2/0 or 4/0 connector each for the positive and negative connection with the battery. The Multiplus II has a built in ATS but there is no reason not to hook it in down stream of your existing ATS.

I found the instructions less than adequate and they do not address the switch on the bottom of the unit it is a 3 position rocker with I 0 II Pretty sure the 0 position is off and am guessing the 1 is for shore power only and the II is in the ATS inverter mode but have no basis for that guess. I think a call to victron is in order or hopefully someone with the Multiplus II installed will enlighten us all. Given what the darn thing costs one would think pretty detailed info would be included. They must plan on having the units installed only by factory certified installers that have paid the big bucks for the training that tells them all the hidden got yas.
 

InMyImage

Solar Enthusiast
Joined
Nov 17, 2020
Messages
146
My image The AC 2 circuit on the Victron only works when there is shore power and does not have "Power Boost" or what ever is on the AC1 circuit to add additional inverter power to make up for lack of current when driveway surfing or running small capacity generator. Not sure why one would want the current draw of running 2 inverters simultaneously if the Multi Plus II has sufficient wattage to handle all the loads. But it may well be a great idea if you have either sufficient battery amp hrs, or sufficient solar to keep the batteries at a reasonable level of charge when running everything.

Jeffa I do not currently have an inverter so I will remove the current converter. Take the shore power wiring from the distribution panel 50 amp breaker and take into a junction box. Run new wires from that junction to the Multi Plus then run wires from the Multi Plus back to the distribution panel 50 AMP breaker. Depending on where I mount the Multiplus this wire run should be 8 to 12 feet. I may or may not put a breaker or cut off switch near the Multi Plus. My thoughts were if I wanted to disconnect shore power from the Multi Plus I could turn off the power pole breaker or just unplug the shore power cord from the box. I plan on mounting the Multiplus very close < 2 feet from the batteries. I did find it interesting the documentation from Victron has the multiplus II connected to the batteries with 2 1/0 cables hooked to the 12 volt positive lugs and 2 1/0 cables hooked to the 12 volt negative lugs. Prior to reading the documentation I had considered running a single 2/0 or 4/0 connector each for the positive and negative connection with the battery. The Multiplus II has a built in ATS but there is no reason not to hook it in down stream of your existing ATS.

I found the instructions less than adequate and they do not address the switch on the bottom of the unit it is a 3 position rocker with I 0 II Pretty sure the 0 position is off and am guessing the 1 is for shore power only and the II is in the ATS inverter mode but have no basis for that guess. I think a call to victron is in order or hopefully someone with the Multiplus II installed will enlighten us all. Given what the darn thing costs one would think pretty detailed info would be included. They must plan on having the units installed only by factory certified installers that have paid the big bucks for the training that tells them all the hidden got yas.
Currently with both AC’s, 2 TV’s plus streaming devices, cellular router, mini computer with 2 monitors running, Residential Refrigerator during cooling , LED lighting, 2 charging iPhones and 3 charging iPads thetrailer power draw is 3040 watts measured by our PowerWatchdog at the pedestal.

I can’t find the rsponse I received, but the answer was that a draw on ACout2 would only receive what is the max available from shore power, so on a 30amp circuit, ACout2 could only draw a max of 30amps. When there is a draw of power on ACout2, whatever remains of the power available for ACout1 would receive assisted power from the batteries. Example: On a 30amp circuit, If ACout2 was drawing 10amps and ACout1 needed 400amps, ACout2 would get it’s full 10amps and ACout1 would receive the remaining 20 + 20amps through PowerAssist from the batteries.

By using the second inverter, in the event of a blackout, blown circuit or boondocking (exclusively overnights while traveling for us) the load from our fridge, and the outlets that power all our TV’s and streaming devices would not reduce the power available from the the MultiPlus so it can better handle our AC’s, small kitchen appliances, etc.

Our trailer is in a repair shop in CA right now so I have not installed anything yet, but we currently have 540ah of LiFePo4 batteries waiting and plan to expand that to 1080ah next Spring.

Hopefully the explanation I was given was correct otherwise I’ll just remove the existing Xantrex inverter and sell it.

As for the power switch, from Rev 02 of the manual page 27:
Power switch - To switch: 1=On, 0=Off, ||=charger only
 

DIDDLYV

Solar Enthusiast
Joined
Mar 1, 2021
Messages
91
Thanks Rev 02 of manual did not come with my unit rather Rev 01 which does not have that information on page 27. Well once you have the unit installed you will see if the explanation given to you was correct. Keep us posted
 

InMyImage

Solar Enthusiast
Joined
Nov 17, 2020
Messages
146
Thanks Rev 02 of manual did not come with my unit rather Rev 01 which does not have that information on page 27. Well once you have the unit installed you will see if the explanation given to you was correct. Keep us posted
You can download new revisions for all their products from each product page on their website. I tend to prefer electronic docs so don’t bother with whatever is in the box.
 
Top