2012 Interstate 3500 inverter question

[TY PECK]

The unit comes with a TrippLite Inverter/Charger
.
The directions say use the Auto/Remote position when needing constant AC power or the Charge Only position when wanting to conserve battery power by disabling the inverter.

I am full timing so have been using Auto/Remote constantly but don't understand what situation I would be in to need to use Charge Only?

Have at it you electric wizards.

Thanks
Ty

[Protagonist]

The inverter/charger can do one of two things: (1) charge your house batteries from a 110V AC power source; or (2) convert 12v DC power from your house batteries to 110c AC power to run appliances. However, it can't do both at once.

In "Charge Only" mode, you're feeding power to the house batteries from the 30-amp external power cord or from the generator, but cannot convert 12v DC to 110v AC. In "Auto/Remote" mode, a computer chip inside the inverter/charger determines whether to draw power from the house batteries or feed power into the house batteries.

My recommendation is to leave the switch in "Auto/Remote" mode whenever you're parked, and change it over to "Charge Only" whenever you're in transit.

The main thing that makes a difference is, the refrigerator is dual 12v DC and 110v AC. As long as there is a source of AC power available, the unti automatically switches to AC. That includes AC from the inverter while you're on the highway with the generator turned off. By switching to "Charge Only" you force the refrigerator into 12v DC mode while you're moving, which puts less drain on the house batteries.

[kaylorsan]

Protagonist, thanks for the details and recommendations.

How do attached solar panels change your recommendation (if at all)?

I've gone thru all of my literature that I received with the van twice now and no where does it mention anything about the inverter panel operation. Very disappointing. One of my tasks today is to learn more about it. I'll post whatever I learn (assuming I learn something).

Currently out in our first voyage since we took delivery...

[Wazbro]

I would say when boon-docking you should use "Charge Only" mode unless you need to use 110v (for tv, coffee pot, ect...) to conserve batteries as much as possible since the conversion from 12v to 110v is not 100% efficient. Also even when not using 110v if the inverter is on it is using 12v.

[Protagonist]

Originally Posted by kaylorsan

How do attached solar panels change your recommendation (if at all)?

No change at all. The solar panel is completely independent of the inverter. As long as you've got sunlight, the solar panel is charging your house batteries. That's true even if you have the battery disconnect switch in the "off" position; the solar panel bypasses the battery disconnect.

Well, with one exception; if you've got the inverter set to "charge only" and you've either got 30-amp shore power plugged in OR you've got the generator running, they're charging the batteries instead of the solar panel doing it.

Originally Posted by Wazbro

I would say when boon-docking you should use "Charge Only" mode unless you need to use 110v (for tv, coffee pot, ect...) to conserve batteries as much as possible since the conversion from 12v to 110v is not 100% efficient. Also even when not using 110v if the inverter is on it is using 12v.

Actually, for a handy guide:
(1) When shore power is connected, set the inverter to "charge only."
(2) When you're running the generator, set the inverter to "charge only." (3) When you're not using shore power or the generator and you want to run an AC appliance, set the inverter to "auto/invert." However, don't even try to run the air conditioner.
(4) When you don't want to run any AC appliances, and you're not hooked up to shore power or running the generator, use the panel on the inverter itself (not the remote panel) and set it to "off."
(5) When you're storing the vehicle, park in the sun, turn off the inverter— as in 4 above— and the battery disconnect, and let the solar panel keep your batteries charged. Caveat: Make sure your propane solenoid is turned off; it sucks 2 amps all the time when it's on, and the solar panel won't be able to keep up since it only charges during daylight hours.

[lewster]

Actually, if your Tripp-Ltie is indeed a true inverter/charger, then it will have an internal transfer switch that powers all 120VAC circuits in your coach; both those that run when the inverter is 'on' and drawing from your batteries and all the remaining outlets. Large-draw electrical items that could drain the batteries quickly when the inverter is on, such as your roof heat pump are normally wired thru the main circuit breaker box and not the inverter circuits.

Also, because of the presence of this internal transfer switch, if you do happen to leave the inverter in the 'auto/on' position, it is incapable of inverting in the presence of shore (or generator) power to avoid internal voltage conflicts.

Here is a diagram from the Magnum Energy manual of how an internal transfer switch operates: http://magnumenergy.com/Literature/M...%20Series).pdf

See the diagram at the bottom of Pg. 42

[Protagonist]

Originally Posted by lewster

Actually, if your Tripp-Ltie is indeed a true inverter/charger, then it will have an internal transfer switch that powers all 120VAC circuits in your coach; both those that run when the inverter is 'on' and drawing from your batteries and all the remaining outlets. Large-draw electrical items that could drain the batteries quickly when the inverter is on, such as your roof heat pump are normally wired thru the main circuit breaker box and not the inverter circuits.

Also, because of the presence of this internal transfer switch, if you do happen to leave the inverter in the 'auto/on' position, it is incapable of inverting in the presence of shore (or generator) power to avoid internal voltage conflicts.

Here is a diagram from the Magnum Energy manual of how an internal transfer switch operates: http://magnumenergy.com/Literature/M...%20Series).pdf

See the diagram at the bottom of Pg. 42

You're the expert (everyone on the Forums always says, "Ask Lewster") and I yield to your greater knowledge. I'm just paranoid over the fact that before I figured everything out (to my limited abilities) I ended up with house batteries that were so depleted I had to dismount them and charge them on a bench. Not an easy task in an Interstate when you have to disassemble the rear sofa in order to access the battery box. So, my advice may be a little bit more cautious than strictly necessary.

[lewster]

Originally Posted by Protagonist

You're the expert (everyone on the Forums always says, "Ask Lewster") and I yield to your greater knowledge. I'm just paranoid over the fact that before I figured everything out (to my limited abilities) I ended up with house batteries that were so depleted I had to dismount them and charge them on a bench. Not an easy task in an Interstate when you have to disassemble the rear sofa in order to access the battery box. So, my advice may be a little bit more cautious than strictly necessary.

Pro',

To err on the side of caution is never a bad thing! Remember that the majority of my experience is from working on the big motor homes with large battery banks, but this is still generally directly transferrable to Airstreams. In the Magnum Inverters that I sell and service, the control panel has one button for the charger section and a separate one for the inverter function.

The charger function is on whenever shore power is present and the inverter function (even with the button depressed) will blink in 'standby mode' until shore power is removed. Even then, you can set the inverter to respond to a specific amount of electrical draw in watts and it will not activate unless it 'sees' this wattage draw from the supplied appliances.

Not sure if the TrippLite has these types of settings. I would definitely take your conservative approach without these features.

[Protagonist]

Originally Posted by lewster

The charger function is on whenever shore power is present and the inverter function (even with the button depressed) will blink in 'standby mode' until shore power is removed. Even then, you can set the inverter to respond to a specific amount of electrical draw in watts and it will not activate unless it 'sees' this wattage draw from the supplied appliances.

Not sure if the TrippLite has these types of settings.

Far as I know, it doesn't. One three-position switch on the inverter proper (auto/invert, off, charge only), a row of dip switches that are "set once and forget" and should be set correctly from the dealer. A remote panel that has only two positions (auto/invert, charge only) and some indicator lights that mean different things depending on where you've got the switch set.

From my own experience, the current draw from just a single switched-off television is enough to kick the inverter to "invert" mode when you've got the inverter set to "auto/invert."

[kaylorsan]

Originally Posted by Protagonist

Far as I know, it doesn't. One three-position switch on the inverter proper (auto/invert, off, charge only), a row of dip switches that are "set once and forget" and should be set correctly from the dealer.

Resurrecting an old topic here...

Over the last few months, I've taken some notes on the Tripp Lite and the DIP switches. I finally got down the project list far enough to take a look at them. Note that I do not really have any issues other than my batteries seem to deplete themselves quicker than than they should (especially with the refrigerator on; even when's it powered by DC). Also, I had a home that was truly 'off of the grid', so I am very cautious/aware of my energy use. That being said, my DIP switches are set different than others have recommended on this board.

The DIP switch descriptions are as follows

A1 - Battery Type
A2 - Charger Enable/Inhibit
A3 A4 - Low AC Input Voltage Point for Switching to Battery
B1 B2 - Load Sharing
B3 - Equalize Battery Charge
B4 - Set Battery Amps

Note that the layout on the Tripp Lite goes (left to right) B4, B3, B2, B1, A4 A3, A2, A1

My switch positions are
down, up, down, down, up, down, down, up

I've seen a # of recommendations to set them as follows
up, up, down, down, down, up, down, up

3 of my switches don't match what others have recommended. They are

B4 - Battery Amps - I'm set at HIGH AMPS. The manual states that 'my batteries will charge at max speed and my RV 12VDC loads will be well supplied. The low charge setting will lengthen the life of my batteries'

A4 A3 - Low AC Input Voltage Point for Switching to Battery. My selections get me to 95V. Other recommendations would set it at 85V

Just curious what other's setting/thoughts are.

Note that I have a 2012 Interstate EXT with solar panels.

[MO_Moderate]

Okay, all my inverter circuits are dead, even when I’m on shore power. All the circuit breakers appear to be okay (I’ve flipped them on and off). Any ideas?

[Rich W]

Originally Posted by MO_Moderate

Okay, all my inverter circuits are dead, even when I’m on shore power. All the circuit breakers appear to be okay (I’ve flipped them on and off). Any ideas?

Hi MO_Moderate, and welcome to the forum. Just as an FYI, this is a very old thread.

The inverter must be turned on. There should be a button in the galley, near the holding tank panel, usually just below. If you push that button on then the inverter should come on.

[lewster]

Originally Posted by MO_Moderate

Okay, all my inverter circuits are dead, even when I’m on shore power. All the circuit breakers appear to be okay (I’ve flipped them on and off). Any ideas?

A '15 should have the Magnum MMS-1012 inverter/charger. There is a set of small rocker breakers right on the Magnum. Have you checked those? Also, your Magnum should pass the 120VAC thru it whenever you are on grid or generator. It's an automatic function so there are no buttons to activate it.

The Magnum will NOT pass thru the 120VAC if you don't have sufficient battery power (IIRC, 9.5VDC) in your house batteries, as the internal relays require 12VDC from the house battery inverter connection to operate.

•*be certain that the Magnum's breakers are set
•*measure your house battery voltage to be certain that it is above 12VDC

Keep up posted!

[MO_Moderate]

Actually, I’d just tripped the forward GFI and it killed all the inverter circuits. Fixed now!