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jelmore
01-24-2008, 12:13 PM
We're in a 2000 Liberty. We've been on 30 amps for a couple of weeks in Mexico and perhaps this is a eureka moment in understanding how Liberty has things wired.

First, the 30 amps we have here come through a 50 amp style outlet. I don't know it gets split up, but we have 120 volts on both legs.

In trying to manage the power we have available, it seems that the red bezel circuits, the ones that run off the inverters if there is no shore power (microwave, refrigerator, water pump, etc.), continue to run off the inverters (batteries) and do not draw on the 30 amps available. I have one battery charger set to 20 amps and the other set to 5 amps. I can have running up to 50 amps and even more when the battery chargers are on without tripping the 30 amp breaker, so I'm guessing that the 25 amps we're putting into the batteries through the chargers plus whatever is in the batteries is available to the red bezel circuits. Whatever is left on the 30 amps coming in is available to all other circuits. If the battery chargers are off, I see the batteries being drawn on heavily for those red bezel circuits and not at all for the other circuits (washer, dryer, water heater, air conditioners, etc.) When we need more amps for those big items, I turn off the battery chargers and then those amps are available.

Perhaps I haven't explained this well. I'm just beginning to understand, I think.

Miss the 50 amp service in both legs, but this is good experience.

Any insight from you folks that have been around a few more blocks?

dalej
01-24-2008, 02:42 PM
Jim, you are not at the Elmirador are you? (San Carlos)

jelmore
01-24-2008, 03:40 PM
Jim, you are not at the Elmirador are you? (San Carlos)

Close, sort of. We drove there yesterday to take a look around San Carlos and eventually got lost in Guaymas! Pretty nice RV park in a nice resort town.

We're at La Playa in Bahia de Kino. We've had enough sand in everything and are ready to head out!

Joe Cannarozzi
01-24-2008, 06:31 PM
You folks should be pretty proud of the blog your putting together. Everyone in the group with one as well.

They are all very good. It is an inspiration to both travel and learn more on the computer to be able to document it as you all are doing so well.

jelmore
01-24-2008, 06:40 PM
You folks should be pretty proud of the blog your putting together. Everyone in the group with one as well.

They are all very good. It is an inspiration to both travel and learn more on the computer to be able to document it as you all are doing so well.

Well, thanks. It's embarrassing it's so out of date. Having too much fun traveling!

Hope someone jumps in on the electrical stuff. I'm sure there's a lot to learn from the experts here.

truk4u
01-24-2008, 08:39 PM
Jim,

I would take a shot at it, but my experience is with Marathon and CC. Jon is your man and he's on his way to Pt St Lucie for our mini rally tomorrow. We will get him hooked up with someones laptop and get you some answers. Roger is traveling with him, so he may pick this up.

Stand by for help.....

VegasDogMan
01-24-2008, 09:55 PM
Question - is the 30A Breaker a Double 30A with a 50A Socket?
If so, see 30-30 Power Cheater config below.
If Single Breaker see 30A below.

OK - From My Experience....Here's how I've run my 97 Liberty.
I have two Heart 2500 Inverters and have run coach on 20A, 30A, 30A-30A with Power Cheater and also 50A.

For 20A -
Set Dip Switches on inverter/charger to limit charge current to 5A each to prevent tripping 20A Shore Breaker. Do not run high current devices such as AC, water heater or Range as they will trip 20A breaker. Inverters will produce enough power to run most normal devices and batteries will charge slowly. You have to keep aware of power you're using and be somewhat frugal.

For 30A - (One 30A Leg feeds entire coach)
Set Dip Switches on inverter/charger to limit charge current to 5A on one and 20A on other to prevent tripping 30A Shore Breaker. Do not run all high current devices at same time. One AC and water heater is ok and range too - best to turn off water heater when cooking. Inverters will produce enough power to run most normal devices and batteries will charge reasonably well.

For 30-30 with Power Cheater (60Amps available - 30A per Leg)
Basically same as 30A but you can run Rear AC as well as EITHER Front or Mid AC but not all three.

50A - (100A Available on two 50A Legs)
Both Inverters set to charge at 30A

For more info see my posting under "Confessions of a Power Cheater" in Sparkys Corner
http://forum.prevostownersgroup.com/showthread.php?t=1401

jelmore
01-24-2008, 10:06 PM
Question - is the 30A Breaker a Double 30A with a 50A Socket?
If so, see 30-30 Power Cheater config below.
If Single Breaker see 30A below.

OK - From My Experience....Here's how I've run my 97 Liberty.
I have two Heart 2500 Inverters and have run coach on 20A, 30A, 30A-30A with Power Cheater and also 50A.



Thanks. Your experience is what I have slowly discovered as best practices. The 30 amp we have now is just that, a 30 amp circuit, so our power management has been vigilant. The cooktop and outdoor grill don't work, so we're not getting any 220 volts and not making any. Everything else works fine, with management. I have kept the chargers at 5 and 20 amps (even when on a 50 amp 220 volt supply. While on 30 amps, the batteries get charged up overnight when not running any ac. We turn off the chargers during the day to run the big load items, though only a couple at a time.

When we got the coach, the chargers were set to 30 amps each, but that used too many amps and we kept blowing circuits so I turned them down. Hope that doesn't affect the batteries in a bad way. They seems to charge fine.

Jim_Scoggins
01-25-2008, 06:12 AM
Instructive thread to us Liberty newbees.
Q. On 30 amps does it matter which inverter/charger you have set for 5 amps and 20 amps?

VegasDogMan
01-25-2008, 04:12 PM
Doesn't make any difference which is set to 20A and which is 5A...

When plugged in to 30A or any other shore power the inverters (internal Transfer Switch) passes all AC through and performs no function other than acting to keep batteries chaarged.

Your total load on 30A service is just that.. 30A max .

jelmore
01-30-2008, 12:56 PM
When plugged in to 30A or any other shore power the inverters (internal Transfer Switch) passes all AC through and performs no function other than acting to keep batteries chaarged.

Your total load on 30A service is just that.. 30A max .

Hmmm. That doesn't always seem to be the case. It seems that the only time AC flows to the red bezel circuits is when the battery chargers are on. If the battery chargers are off, then those circuits seem to run off of the inverters only and all the 30 amps go to the other circuits. I have seen the total volts in the 40s and low 50s with the battery chargers off without tripping the 30 amp breaker and the only explanation I can imagine is that those amps over 30 are being supplied by the inverters.

I have always wondered if my inverters are wired strangely since they only provide AC to the red bezel circuits if the battery chargers are on.

VegasDogMan
01-30-2008, 05:57 PM
The Shocking Truth....

On the Freedom 25 inverters there are two sets of input wires. One set for Charger and one set for Transfer Switch. Liberty ties both sets together so that when you kill the "Charger" breaker on your AC Breaker Panel you remove all shore power from the Inverter Input...

No power to charger and no power to Transfer Switch... Inverter then takes over and produces AC from battery power. Just like when you unplug coach.

Labelling on Breaker is misleading.!

jelmore
01-30-2008, 06:33 PM
The Shocking Truth....

No power to charger and no power to Transfer Switch... Inverter then takes over and produces AC from battery power. Just like when you unplug coach.
\

So then, is this correct?? --> When plugged into a 30 amp circuit and both battery chargers off, the inverter output from both inverters go into a common pool (as I presume the charging function does), and that pool powers the red bezel circuits while all of the 30 amps AC is available to the other circuits. When the battery chargers are on, then only 30 amps is available to all circuits, including the battery chargers.

Sorry to labor on this -- maybe I haven't read the instructions enough times to understand that way Liberty does this. All of this is really just in the interest of power management when 50 amps of 240 volts isn't available.

jack14r
01-30-2008, 07:40 PM
On mine there is inverter 1 (left side of electrical panel) and inverter 2 (right side) they do not pool/combine.#1 inverter supplies power to the refrigerator etc. and #2 supplies power to the water pump etc.I can't remember every item that has the red bezel around it.

VegasDogMan
01-30-2008, 08:55 PM
On my liberty with both charger breakers OFF, each inverter powers four or five circuits.
They DO NOT Pool Power - it would be difficult to phase lock and synchronize the output of two inverters.
No AC water pump circuit on my coach - have 12V DC Water Pump

From my memory circuits powered by each inverter are... (Inverter circuits have RED RING around breaker)


Inverter #1
1. Fridge
2. Coffee Maker
3. TV
4. Front Outlets
--------
Inverter #2
1. MicroWave
2. Rear Outlets
3. Air Compressor
4. Outside Entertainment Center
5. Circuit for Outside Outlet on one of the inverters.

If you turn off the small switch on Inverter Monitor Panel you'll lose the four circuits belonging to that inverter.

gmcbuffalo
01-30-2008, 11:04 PM
"phase lock and synchronize the output of two inverters.

Could you explain what is a "phase lock and synchronize".

GregM

gmcbuffalo
02-01-2008, 12:57 AM
Another question.

with your inverter chargers turned off your inverter then powers the two inverter circuits you describe. Now if you turn off the inverter function are you telling me you have now power going to Inverter Circiuts 1 and 2 and those appliances do work?
GregM

jelmore
02-01-2008, 03:32 AM
Another question.

with your inverter chargers turned off your inverter then powers the two inverter circuits you describe. Now if you turn off the inverter function are you telling me you have now power going to Inverter Circiuts 1 and 2 and those appliances do work?
GregM

No. If I turn off the inverters, then all the circuits that those inverters power are turned off, just as VegasDogMan said. Those circuits stay powered whether the chargers are on or not, but not if the inverters are off. If the chargers are on, then those circuits are powered by shore power or generator power. If the chargers are off, then those circuits are powered by the inverters (batteries).

That's my understanding, anyway.

Jim_Scoggins
02-01-2008, 07:11 AM
OK. With the inverters off, those items serviced by the particular circuit are lost.
Using the refrigerator as an example. With an inverter failure one has lost the refrigerator.
The options are:
To manually by pass the inverter at the inverter itself--join the wires.
Replace the bad inverter charger with a good one.
Get at the refrigerator cord so as to run an extension to it from another outlet controlled by the other inverter.

Hence, Jon's work to set up an inverter by-pass switch.

Q1. All this still begs the question. Why in the world did Liberty set it up this way? What advantage is there to this set up?

Q2. Why was not an inverter by-pass incorporated from the get-go? Many so called lesser coaches have an inverter by pass.

Q3. Are the newer Liberties still set up this way?

I guess I am still really missing something and will differ to any and all GURUs.

jack14r
02-01-2008, 08:54 AM
The Heart 2500 Freedom Inverter has a set of contacts in it that allow it to bypass if shore or generator are being used.Liberty's electrical system does not load share,therefore if there is an inverter fails, every circuit will work on gen. or shore power.I had a inverter failure in November and it was a minor inconvenience,I had to start the gen. to have water.Other designs that load share will not bypass the inverter and those circuits will not have current. In those electrical designs it would be important to have a bypass as Jon has described in other threads.

Joe Cannarozzi
02-01-2008, 06:24 PM
This is the simple solution to automatically switching power to shore or gen. when the inverter is not on that came standard in Heart inverters that were made as far back as 85.

2239

2238

I had to replace the one on ours.

I'm with you on this one Jim.

I have yet to hear an explanation that sufficiently gives good reason why this did not remain a standard feature.

Jon Wehrenberg
02-02-2008, 11:35 AM
The information Lee provided relative to how things work is correct.

Not to belabor the issue but to elaborate to help explain things here is how the electric flow path works.

Shore power goes through the transfer switch to the panel. The transfer switch is prioritized. It passes (in the order listed) power to the panel. First inverter, then shore, and finally generator power. With shore power at the panel the two inverter switches in the panel send shore power to the inverters. The inverter switches in the Liberty AC panel on my vintage coach are 50 amp, and they each have two 10 gauge stranded wire sets going into the inverter. One set is connected to the inverter AC input which when hot will transfer to the AC output, and the second set is connected to the inverter battery charging circuit input wires.

Once the inverters see incoming power their internal transfer switch closes the circuit sending the shore power back to the red marked circuits and to the battery charger section of the inverters.

The inverters, in the presence of shore power will not use battery power to supply any AC power requirements.

If the inverter switches in the AC panel are in the off position the red marked circuits will not get any AC power from any source, inverter, shore or generator. A by-pass switch is required to enable that which is why I made the modification to my coach.

truk4u
02-03-2008, 09:18 AM
This is good information and all converters are not the same as Jon previously pointed out. My 97 Marathon functioned the same way as Jon just explained, if you lost an inverter, you had no A/C power for that particular leg. I was going to install a bypass switch, but sold the bus.

My CC is different. You can shut off both inverters and it has no effect on shore or gen power.