Trailer power calculator - who has done it?

[Acheron2010]

There are a number of solar size charts and calculators on the Internet - this is one example.
Has anyone performed a baseline survey of their stock late model TT? While I am personally interested in a Flying Cloud FB27, almost any model will do.
Lights, furnace, fan, stereo, detectors, microwave, powered awnings, water pumps - anything and everything electrical in your unit before adding your own coffee maker, toaster, etc.
It would be nice to say the Basecamp has X total amp hours per day and the Classic 30 has Y total amp hours per day. Then we could add or subtract our own accessories to determine our personal use, then size batteries, solar panels and/or generators accordingly.

[Vantair]

I have and still working on its refinement.

VERY surprising how each device yanks battery power that adds up. And why stock bats don’t last long boondocking.

Based on our 2005 25ft Intnl CCD SS model.
We have painstakingly (and accurately) measured every powered device individually
At the battery box and logged current drain.
AC converter disconnected.

Loose numbers from memory::

With 2 Stock Interatate 81Ah batteries ea fully charged voltage resting 3 days to 12.80v.

ie: Did you realize your Dometic fridge on gas and battery “only” draws @16.32 amps per day-.68ah. (Or 7.5a with factory door heat strip disconnected with easy switch mod.)

The “Use” Power with stock LED / switch draws 1.5 amp/day ? (Changed that led and resistor to now draw mere 1/115 of that). Stock so wasteful.

The Fantastic fans draw 1.25 - 1.57 - 1.75 amps pending speed setting ?

Range hood fan draws 1.25a

Water pump varies 1.5a to 5.5 A pending pressure when oscillating.

Furnace fan 7.5A.

YMMV Hope to complete it one day ...

[Paprika]

Here are a few more numbers for you, based on my 2017 International 27FB. These were measured by my shunt-based Victron BMV-712 battery monitor, which sees all power going into and out of the batteries.

furnace: 6.0 A

water heater: 0.6 A when running (presumably due to solenoid valve)

dinette sconce lights: 0.3 A apiece

bedroom reading lights: 0.3 A apiece

bedroom ceiling lights: 0.1 A (minimum) - 0.8 A (maximum)

kitchen/dinette ceiling lights: 0.1 A (minimum) - 1.7 A (maximum)

cabinet lights (per cabinet; 3 lights): 0.6 A

bathroom, shower exhaust fans: 1.2 A apiece

water pump: 1.5 A - 5.5 A

Clarion stereo: 0.7A - 1.0 A (but I’m not listening to loud music)

I recently installed Fan-Tastic 7350 upgrade kits, which (among other things) replace the old power-wasting resistor-based speed controller with a PWM type that offers a dozen speeds, including whisper-quiet extremely slow. On the slowest speed it draws less than a tenth of an amp, while on the highest speed it draws 2.1 amps.

A few numbers from items not installed by the factory:

MacBook Pro: 4.5 A (maximum, when charging from a low battery state)

Dickinson P12000 wall fireplace fan: 0.1 A

AirSense 10 CPAP: 0.3 A (without hose heat), 4.5 A (hose heat @ 75° F.)

Caframo 12 V portable fan: 0.2 A (low), 0.4 A (high)

[Paprika]

P.S. - I meant to include a link to the Fan-Tastic 7350 upgrade kit. Not cheap, but it gives you a rain sensor with automatic lid closure, wireless remote control, bidirectional fan, more than a dozen speeds including extremely slow/quiet, and very low power consumption at the slow speeds.

[Vantair]

Paprika ,

Great job ! That’s the awesome knowledge out here on forums we’re talking about !
Like the fan mod you mentioned.

“Off” saves power too ! Ha.

[YippieKiYa]

Great info. Thanks to both the OP and Paprika. Would never have thought about the door heater in the fridge, and who would’ve thought the “use” switch would consume so much...

[rmkrum]

Great data. I’m going to have to do some research and measuring on my draws.

[Papou]

Originally Posted by Acheron2010

There are a number of solar size charts and calculators on the Internet - this is one example.
Has anyone performed a baseline survey of their stock late model TT? While I am personally interested in a Flying Cloud FB27, almost any model will do.
Lights, furnace, fan, stereo, detectors, microwave, powered awnings, water pumps - anything and everything electrical in your unit before adding your own coffee maker, toaster, etc.
It would be nice to say the Basecamp has X total amp hours per day and the Classic 30 has Y total amp hours per day. Then we could add or subtract our own accessories to determine our personal use, then size batteries, solar panels and/or generators accordingly.

I made a such survey few years ago in my 2011 Flying Cloud 23 FB for my solar panel and additional battery calculation. See Excel sheet attache. Hope this help.
If you need additional info or English translation, send me a private message.
Michel

[Casto]

Great information Paprika. Just curious what your average daily power consumption has been. I’m in the process of upgrading to a new lithium battery system on our 2017 AI and want to make sure I size it right..

Thanks.

[romaa.13]

Originally Posted by Papou

I made a such survey few years ago in my 2011 Flying Cloud 23 FB for my solar panel and additional battery calculation. See Excel sheet attache. Hope this help.
If you need additional info or English translation, send me a private message.
Michel

I am having solar panels with a total of 300 watts installed and was debating on adding a 2000 watts inverter or not. Thanks for your calculations.

[KK4YZ]

Originally Posted by Papou

I made a such survey few years ago in my 2011 Flying Cloud 23 FB for my solar panel and additional battery calculation. See Excel sheet attache. Hope this help.
If you need additional info or English translation, send me a private message.
Michel

Papou,
Thanks for posting this. While I don’t speak French I was able to figure out most of it😀 except which line corresponds to the gasket heater on the refrigerator.
Can you point me to it?
Thanks much!

[Papou]

Good Day KK4YZ,

About the Excel file, I can translate in English if this help you!
I dress this table to help me for my solar panel requirement to have a full autonomy in boon docking along with a "carry on" AGM battery that I bring in a such situation. I can share these information as well (in English).
Just ask!

And about your question about the "fridge gasket heater":
We address this point in our last year WBCCI meeting. One member experienced a similar issue and:
We "discover" an hidden phantom load:
In his Airstream trailer, (2014 International 25 feet) the installed DOMETIC RM-3762 refrigerator have an "heater" around the door that the manufacturer call: "Climate Control Heater" to prevent sweating in high humidity. This heater is powered in a permanent mode as soon as the refrigerator is "on".
See attached page # 12 of the service manual of the unit.
This heater draw nearly 1 Watt (.890 W) from the DC circuitry. In other term: 1.68 Watt-hour or 21.34 Watt-Hour per day.
The wire that feed this 24 ohms resistor was cut by the owner of the trailer; for his usage (no high humidity camping) this heater is not required.
And he "saved" 24 watt-hour per day!

Hope that help.

Michel

[KK4YZ]

Originally Posted by Papou

Good Day KK4YZ,

About the Excel file, I can translate in English if this help you!
I dress this table to help me for my solar panel requirement to have a full autonomy in boon docking along with a "carry on" AGM battery that I bring in a such situation. I can share these information as well (in English).
Just ask!

And about your question about the "fridge gasket heater":
We address this point in our last year WBCCI meeting. One member experienced a similar issue and:
We "discover" an hidden phantom load:
In his Airstream trailer, (2014 International 25 feet) the installed DOMETIC RM-3762 refrigerator have an "heater" around the door that the manufacturer call: "Climate Control Heater" to prevent sweating in high humidity. This heater is powered in a permanent mode as soon as the refrigerator is "on".
See attached page # 12 of the service manual of the unit.
This heater draw nearly 1 Watt (.890 W) from the DC circuitry. In other term: 1.68 Watt-hour or 21.34 Watt-Hour per day.
The wire that feed this 24 ohms resistor was cut by the owner of the trailer; for his usage (no high humidity camping) this heater is not required.
And he "saved" 24 watt-hour per day!

Hope that help.

Michel

Michel, thank you. Yes, if you already have an English version of that spreadsheet I would very much like to have a copy.
Spring is just around the corner and we’re itching to go camping again!
Regards,
Jim

[Papou]

Good Day Jim,

I will post an English version later this week on this thread. I am a little busy at this moment to proceed to the installation of maple planks in my house (500 sq.feet)
Michel

[Al and Missy]

Here is my spreadsheet for estimating power consumption and the solar capacity required to support it. The sun hours per day is a variable you have to assess for yourself and depends on latitude, season, weather, and shading due to obstructions.

To avoid confusion, I'll throw in a little semantics/terminology.

Volts - the electrical equivalent of water pressure that forces current through a load

Amps - the electrical equivalent of water flow in gallons per minute. Amps, however are dimensionless, i.e. it represents the current at a single instant in time, thus amps per day is a misnomer. This is a common error, I have read vendor spec sheets that specify amps per day.

Amp-hours - current times time. A load that draws 1 amp continuously draws 24 amp-hours per day, 168 amp-hours per week. This can be directly related to solar system output by multiplying the average amps output times the solar hours per day.

Watt-hours - simply the amp hours times the voltage pushing the current.



Al

[Papou]

Originally Posted by KK4YZ

Papou,
Thanks for posting this. While I don’t speak French I was able to figure out most of it😀 except which line corresponds to the gasket heater on the refrigerator.
Can you point me to it?
Thanks much!

As promise, you will find the English version of the Excel sheet that I use to estimate my energy requirements en boondocking.
The energy requirement of each equipment was measured in the fuse block at the converter unit of my 2011 23FB travel trailer.
You will find also few lateral notes of the picture of this sheet.
Michel

[KK4YZ]

Michel,
Thank you very much. There’s a lot of work that has gone into this.
Regards
Jim

[Airabel]

I'm having difficulty understanding these numbers. Probably because I'm not an engineer. Need help.
We have a 16' Sport with a group 24 stock battery ( 690 amp I think ) and an 80 watt Zamp solar panel. We boondock a lot in the summer with no problems. I'm worried about this Spring.
The only equipment that we have to have running each night is the Furnace, maybe a light and minor items like co detector. If the Furnace pulls 7 amps, how long can I run the Furnace before I have to recharge the battery with a 80 watt panel? Assuming it's a sunny day of course.
I'd like to do one of these charts for the Sport but lack the understanding.

[Papou]

Good Day Jim,

And the people who are concern.

Looking to the thumbnail image include to my post, the resolution is too low to read it and to understand the comments...

Sorry for this boo boo!

If you need a HiRez version of the thumbnail picture show in my reply, just send me a private message, and I will send you an e-mail.

Michel

[Airabel]

On the above Boondocking Energy Chart, why do you use commas instead of decimal points?
For example Fan: 1,1 Amp instead of 1.1 Amp