2012 Tiffin 40 QBH - Inverter- Shore Power

[jerryd13]

Hello friends, I am here to ask all of you Tiffin Owners who have drawings to allow you to troubleshoot your Incoming electrical power from shore or from the generator. Does your 115 volt refrigerator, microwave, roof top Air Conditioners and receptacles n your coach, get powered directly from the 115 vac Breaker panel, that is being fed from which, the shore power/Gen, or does the inverter first get this 115/230 vac power then send it along to the panel. I AM NOT SURE, so I am asking the following questions, and I have included a rough single line diagram- just my guess, can any of you tell me with 100% certainty what is correct.

1. The question noted above.
2. Is the house battery Charger built into the inverter to charge the house batteries or is this a separate device.
3. Do all 115 vac loads come from inverter, and not directly from the generator or shore power.
4. Does anyone have a correct drawing or diagram that shows this system as it really is wired.


Thank you
Jerry

[twinboat]

Someone will supply exact wiring but your shore power and generator power go to a automatic transfer switch.

That ATS senses the incoming power and sends it to the mains circuit breaker box.

Some of that power ( 30 amps ) is then directed, with a breaker, to the inverter/charger.
The inverter/charger charges the batteries and allows power to pass thru to some outlets and in some cases microwaves.

When the inverter/charger doesn't have power to it ( no generator or shore power ) it creates 120 volt power for the same things I just listed.

[lllkrob]

On a Tiffin coach shore power or generator directly power all AC receptacles through the transfer switch with the inverter only providing DC to charge the coach batteries. The chassis batteries are charged by the AC powered battery minder in the right rear storage compartment. On coach battery power the inverter provides AC power to SOME receptacles. These are lights, most AC wall receptacles including the residential refrigerator, except the microwave on some coaches, the dishwasher, and the washer dryer if equipped. Also the air conditioning units are not powered by the inverter.

As far as I know, Tiffin does not supply wiring diagrams for their coaches.

[Props2]

Twinboat has it covered at the front end. I can tell you that on my model, ALL interior outlets are on the inverter circuit. Those outlets includes the refrigerator, microwave, all 4 tv's and electronics cabinet and antenna's. The inverter will be in pass-thru if you are on shore or gen power. You do need to be somewhat mine full of your plugged in loads in either pass-thru or battery's. On my inverter model,and possibly yours too, you get a bump in power with help from the battery's while on shore or gen power. (800w IIRC)
The items not on the inverter (sub-panel) would be the 3 ac units, aquahot heater element, engine heat outlet, vacuum, induction cooktop,washer and dryer and......I think that's it.

I just shake my head on how Tiffin circuited my coach.

[Props2]

Originally Posted by Props2

Twinboat has it covered at the front end. I can tell you that on my model, ALL interior outlets are on the inverter circuit. Those outlets includes the refrigerator, microwave, all 4 tv's and electronics cabinet and antenna's. The inverter will be in pass-thru if you are on shore or gen power. You do need to be somewhat mine full of your plugged in loads in either pass-thru or battery's. On my inverter model,and possibly yours too, you get a bump in power with help from the battery's while on shore or gen power. (800w IIRC)
The items not on the inverter (sub-panel) would be the 3 ac units, aquahot heater element, engine heat outlet, vacuum, induction cooktop,washer and dryer and......I think that's it.

I just shake my head on how Tiffin circuited my coach.

Edit: in red. I don't think that statement is correct. It seemed to me I read that somewhere but looking at the manual this morning, I could find nothing. Electrically, I don't see how that's possible anyway. The 2800w is a peak 5 min limit. (2000w+ 800W)
I should not be posting that late at night.

[jerryd13]

Dear RV Friends, I wanted to thank all who are providing helpful information on the of the incoming 115/230 vac electrical power and how it interfaces with the on board (ATS) Automatic Transfer Switch and the 115 vac/ 12 vdc
inverter and charger systems.


REVIEW SKETCH BELOW



First, I have learned that the ATC will sense the incoming electrical power, and if 115/230 vac is available from the shore cable, the switch will move to the SHORE POWER POSITION.


Second, If adequate 115/230 vac is not available from the shore, the switch will transfer to accept power from the operating generator, if such exists.


Third, The ATC is connected ( see sketch below) to one pole of the 50 amp 2 pole circuit breaker, that supplies 1/2 of the 115/230 vac panelboard.


Fourth, The Inverter has two sources of power, one source is coming from the bank of 12 vdc house batteries, where the inverter/charger takes this energy to supply 115 vac to the other pole of the 50 amp circuit breaker that supplies power to vac panelboard circuits as shown on the sketch.


Fifth, The Inverter also supplies 12 vdc power to the DC panelboard/fuses and dc circuits on motor home.


Sixth, The Alternator on the Motor Home will charge the two start batteries, and in addition, when the engine is running, a 12 vdc solenoid contact will close and allow the engine alternator to also charge the House Batteries as you drive down the highway.


Seventh, I cannot tell you each and every load and how it is supplied and from where. but on my 2012 GBH it is as follows.


115 vac from 1/2 of panelboard supplied from inverter feeds,

• Refrigerator
• Televisions
• Microwave
• Kitchen receptacles
• I am not sure how my ,? Washer-Dryer are fed, roof A/C, hot water.

115 vac from the other 1/2 of panelboard feed all other 115 vac loads.


*You must open your panelboard cover to see which loads come from which bus on panel.

[Props2]

Jerry, are you sure you are looking at this right?
You have what you believe is one panel, but really its one panel and a sub-panel. Its really hard to tell but the two are electrically isolated even though its in one enclosure. You may be looking at a single handle breaker, buts its really a two pole.(220v from the ats) Your non-inverter loads like your ac's,washer/dryer,etc AND your inverter input is on the main panel. Your inverter output will be like a single pole main energizing the sub-panel which energizes the "inverter " circuits( other breakers) in your coach. From your diagram it looks like the inverter is wired single in/ single out. Anyway, take a closer look. IDK, maybe Tiffin wired things differently in 2012?

[twinboat]

Originally Posted by jerryd13

Dear RV Friends, I wanted to thank all who are providing helpful information on the of the incoming 115/230 vac electrical power and how it interfaces with the on board (ATS) Automatic Transfer Switch and the 115 vac/ 12 vdc
inverter and charger systems.


REVIEW SKETCH BELOW



First, I have learned that the ATC will sense the incoming electrical power, and if 115/230 vac is available from the shore cable, the switch will move to the SHORE POWER POSITION.

Correct shore power is DEFAULT position


Second, If adequate 115/230 vac is not available from the shore, the switch will transfer to accept power from the operating generator, if such exists.

Generator has PRORITY, it will switch to it regardless of shore power.


Third, The ATC is connected ( see sketch below) to one pole of the 50 amp 2 pole circuit breaker, that supplies 1/2 of the 115/230 vac panelboard.

Both poles transfer thru the ATS. You can not switch 1 leg of 240 volt service.l

Fourth, The Inverter has two sources of power, one source is coming from the bank of 12 vdc house batteries, where the inverter/charger takes this energy to supply 115 vac to the other pole of the 50 amp circuit breaker that supplies power to vac panelboard circuits as shown on the sketch.

Inverter only passes shore power thru it, if avalable.

Fifth, The Inverter also supplies 12 vdc power to the DC panelboard/fuses and dc circuits on motor home.

No, there will be a seperate cable supplying 12 volt power from the battery bank.


Sixth, The Alternator on the Motor Home will charge the two start batteries, and in addition, when the engine is running, a 12 vdc solenoid contact will close and allow the engine alternator to also charge the House Batteries as you drive down the highway.

Correct.


Seventh, I cannot tell you each and every load and how it is supplied and from where. but on my 2012 GBH it is as follows.


115 vac from 1/2 of panelboard supplied from inverter feeds,

• Refrigerator
• Televisions
• Microwave
• Kitchen receptacles
• I am not sure how my ,? Washer-Dryer are fed, roof A/C, hot water.

115 vac from the other 1/2 of panelboard feed all other 115 vac loads.


*You must open your panelboard cover to see which loads come from which bus on panel.

I answered your assumptions between them, above.

In most breaker panels, every other breaker is tied to a leg.

[ernieh]

I'm not sure that I follow some of the posts in this thread, but my previous coach was a 2012 Phaeton. The following statements are true as best as I can remember.

The breaker panel is in fact 2 separate panels. One part contains all of the high load items like washer, dryer, ACs, block heater, water heater, etc. That side also feeds the inverter/charger. The circuits on the right side of the panel are fed from the inverter at all times. However, when AC power is available from the generator or post, the inverter uses a pass through relay to provide power to the inverter circuits. When AC power is not available to the inverter, the inverter uses battery power to supply those same circuits.

[vsheetz]

Shore or genny -> transfer switch -> main breaker/panel (main branch circuits - air conditioners, laundry...) -> inverter/inverter bypass (this is the breakers on the inverter itself) -> sub panel (inverter branch circuits - most outlets, TVs, residential refrigerator, microwave...).

[jerryd13]

Vince & Susan,

Thank you for the information. I am now pretty clear on my system, but for awhile I was certainly not understanding it at all.

Take care friends


Jerry Dunford

[andy29847]

I had some of the same questions about my coach (Alpine). In my case, the answer is complicated. Below is the drawing I made. Note that the items listed on the main AC panel are powered directly by the shore power or generator. The items listed on the AC sub panel are powered through the inverter. The items on the DC panel are powered by the inverter when on shore or generator power, and powered by the batteries when boondocking. On the charging side, the Heart Echo Charger charges the house batteries after the chassis batters are fully charged.

[twinboat]

Originally Posted by andy29847

I had some of the same questions about my coach (Alpine). In my case, the answer is complicated. Below is the drawing I made. Note that the items listed on the main AC panel are powered directly by the shore power or generator. The items listed on the AC sub panel are powered through the inverter. The items on the DC panel are powered by the inverter when on shore or generator power, and powered by the batteries when boondocking. On the charging side, the Heart Echo Charger charges the house batteries after the chassis batters are fully charged.

Your 12 volt items are powered by your house batteries all of the time.

The inverter/charger charges and maintains your house batteries, while on shore/generator power.

You will find that your house power is run thru your battery disconnect and on to the battery, not the inverter/charger.

[andy29847]

Originally Posted by twinboat

Your 12 volt items are powered by your house batteries all of the time.

The inverter/charger charges and maintains your house batteries, while on shore/generator power.

You will find that your house power is run thru your battery disconnect and on to the battery, not the inverter/charger.

I don't believe you are right. The house batteries may be in the circuit all the time, but they are not providing all the power. I agree with you on the location of the disconnect. I'll work on my drawing. In the meantime, I have this out of my inverter/charger manual.