Vantare Inverter Config

[travelite]

Folks,

I PM'd Ben Cummings with the following questions regarding Vantare inverter configuration. With his permission, I'm posting his reply to the forum:

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Hi Ben,

I understand that Vantare inverters are set up differently than most in that all house circuits go through the inverters? Apparently this means that the owner has to manage the power dispensed by the inverters so as to not overload the them when off shore or genny power.

I'm trying to understand the difference in how the Vantare is set up compared to my LXi. My LXi uses 2 3000W Trace inverters and a 15KW generator. The 110V load center has 2 input and 2 output breakers per inverter. Certain loads are not connected to the inverters: engine heater, toe space heaters, etc, but 2 roof top A/C's are wired so I can easily draw more power than the inverters can source; in other words, I have to manage power. Furthermore, the LXi has an external automatic transfer switch that switches between shore and generator power. There's no inverter bypass, but I don't need one - if my inverters are pulled, the load center still connects outside shore/genny power to the circuit breakers. If an inverter detects an outside source of 110V it switches to converter mode.

What are the striking differences between my LXi behavior and the behavior I would get from the Vantare in terms of power management, inverter bypass, and shore/generator transfer switching?

What follows is Ben's reply:

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Hi David,

Thank you for the excellent question regarding inverters. I am actually co-hosting a seminar in Kerrville with Jon regarding inverters and their differences.

In short, however, yes you are correct. Vantare coaches do run all power through this series of inverters. Load management is the customer responsibility, however a down-stream load management system, similar to what I designed into the Parliament Coaches can be added to limit/reduce/unload certain items when shore or gen is not available. I had tried to work with the Sanford engineers when I was still employeed by them to incorporate this valuable idea into the Vantare coaches, but to no avail.

Let me say that the inverters in the coach you are looking at were designed for the alternative energy market, and are actually capable (in the non-RV software) of selling power back to the utility company. In order to do this, they do something that no other RV inverter can do. These inverters actually synchronize up with and are perfectly in phase with the AC input source. They either transfer current to their transformer to charge batteries by lowering their output voltage setting, or augment power of the AC source by raising their output voltage above the source. This allows them to either use power to charge the batteries or augment the AC input if the shore cord limit set on the inverter is exceeded. The advantages to how the Vantare and Parliament coaches are set up is that since all the power going through the coach is seem by them, you can actually set the AC1 input (shore cord) so that you don't trip a shore power breaker while living in the coach, without having to constantly be aware of what the load on the cord is for everything you use. This allows temporary loads such as microwave, hair dryer, etc to temporarily run (by the inverters actually taking energy out of the batteries to run these) without tripping a shore breaker.

Another advantage to the SW-series being "in synch" is that power transfers are virtually seemless. If the generator were to be started, the inverters first disconnect from the shore cord input and then proceed to slowly phase shift their output to synchronize up with the generator source and then "lock in" the contactor that parallels the inverter with the generator. There is normally no abrupt transfer of power which can make clocks reset to zero, etc.

One more advantage to these inverters is that since their output is EXACTLY like generator or shore power, and not a modified block square wave, motors run cooler and clocks run precisely on time, and ceiling fans don't hum like they would when running on the inverters like are installed in your LXI.

While most other inverters have a "shore cord size" input setting, since they do not actually synchronize up with the shore cord, they only attempt to keep you from tripping the shore breaker by cutting back the battery charging. They are incapable of making up the difference/augmenting the shore cord power since they are not actually synchronized with their AC source. The inverter circuitry is dormant until the AC source is removed.

The only disadvantages to the Vantare is that:

1) You will have to perform the "unloading" before unplugging the shore cord, or transfering to generator, or just running down the road on inverter.
2) You will have to be a bit more interactive...i.e. you will have to set the proper "Shore Cord size" on each inverter to get all the benefits and prevent a shore breaker trip.

In summary, if you don't mind being more interactive with your coach power system, at least in the initial setup, then you will see much more capability than you have experienced with the LXI. It can be a bit confusing if you are the type of person who does not want to have this level of understand or interaction. There are those people who simply want and ON/OFF button for inverters, televisions, etc. If that is your personality, then the Vantare is not for you. If you don't mind understanding, and want to be able to no only know what is going on, but also to be able to have the flexibility to really use what the capabilities of these inverters offer, then this IS the coach for you.

As I said, we can add a load managing system to what Vantare already has done if that is something you budget in from the beginning. I'll have to work up a quote for this addition, which would take out of the equation the possibility of inverter overload, which is really the major drawback to the Vantare setup/use of these inverters.

I hope you are going to attend the Kerrville rally, as I would love to be able to thoroughly go over with you what I have put here in brief.

Sincerely,

Ben Cummings
Coach Worx LLC

[scott13]

Ben, What do you mean by "unloading" when unplugging from shore power? Also if you're in a campgroud with 30 amp service I assume you would set both inverters to 28 or 30 amps. Is that correct? I was also told to set the inverters 2 or 3 amps below actual shore power to prevent the breakers from popping since most breakers won't really handle what they are rated for like set shore power at 47 amps for a 50 amp service. My 2001 Vantare kept popping the 250 breaker till I discovered the number 2 inverter was set on 30 amps not 50.

[nrhareiner]

Good morning Scott,

I may be wrong, but with the 30 amp supply, all you have isa total of 30 amps. With the 50 amp supply usually you have two legs, each with 50 amp supply. So if plugged into 30 amp supply you should set the inverters to around 13-14 amps each. At least that is how I run my inverters. Hope this helps.

[scott13]

Yeah, That's kind of confusing that with 50 you set it at 50 but with 30 you set it at 15. Electricity is strange.

[nrhareiner]

Yes, it can be confusing. Normally with our "50 amp" hookups, we really are hooking into two separate 50 amp legs. That is why we can set the inverters to 50 on each. When we hook up to 30 amp service it is one leg at 30 amps. So if have two inverters we can only share that one 30 amp leg.

[scott13]

Anyone else know what Ben means by unloading when unhooking from shore power?

[bonhall41]

I think he means turning off air conditioners and any other heavy draws. We were instructed to always do that when switching power sources and also when turning on the coach engine.

Bonnie

[jack14r]

If I understand the setup Ben is describing correctly it seems that the Vantari Coach is always using the inverter to convert power,I guess that if one fails it would necessary to have a bypass switch to then get power to some items.Is this correct?

[nrhareiner]

In the Vantare inverter setup, you can overload the inverter if unplugging from shore power or turning off the generator without checking loads. Each inverter will handle 35 amp draw without shutting down due to over load. So if have 4 AC running, electric hot water etc you would overload the inverters.

Also, at least on my Vantare, there is a switch in the bay that allows either the normal method of getting electricity to the coach, using generator only, using shore power only, or using the inverters only.

Have fun at Buckhorn, wish I could make it this year.

[travelite]

If I understand the setup Ben is describing correctly it seems that the Vantari Coach is always using the inverter to convert power,I guess that if one fails it would necessary to have a bypass switch to then get power to some items.Is this correct?

Jack,

The way I understand it, all loads are wired through the inverters, even though the summation of the loads exceeds the inverters 4000W ability. When on shore or genny power, the inverter passes the shore/genny power along to the loads. If the voltage starts tapering off, then the inverter can step in to supply more power to the grid (shore or genny). When switching off the shore or genny power and migrating to inverter power, some of the loads have to be pruned or else the inverter will be overloaded and the circuit breakers will pop; i.e., some sort of automatic or manual power management must take place. I'd like to hear more from Vantare and Parliament owners on how they handle this transition. If this isn't correct, please Vantare owners, correct me.