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Topic: When to run the genny on voltage read (Read 687 times) previous topic - next topic

When to run the genny on voltage read

Ok. First 5 day dry camping in the FT, I'm used to bars, not voltage on house battery reserve. They would go from 13.4 down to 12,1 volts. At what number is it wise to run the genny? I ran it twice a day anyway but would be nice to know a low point to not go below. It was a good 1st time ride and camp. 650 miles in 5 days. Lost my engine start batteries in Green river Utah but Napa had 2, 1000 watt maintenance free in stock. Turned out they were 5 years old and 850 amps.
Retarder is great but sure is a learning curve on hills. The ride and quietness is wonderful! Think it's going to be fun. Love the large fuel tank and water and sewer capacities.
Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: When to run the genny on voltage read

Reply #1 –
With no load don't go below 12.2
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: When to run the genny on voltage read

Reply #2 –
If dry camping and not using any 110 power from inverter, you might just turn it off till you need it.  It draws power all the time. Also if planning to use microwave or other heavy power, turn Generator on rather than use inverter for that load.
Eric & Nancy
1999 36 Ft. U320 WTFE
2016 GMC Terrain

Re: When to run the genny on voltage read

Reply #3 –
Quote from: Eric Rudolph –
If dry camping and not using any 110 power from inverter, you might just turn it off till you need it.  It draws power all the time.

"might" is not a strong enough recommendation.  ABSOLUTELY turn off the inverter unless you are using it.  And as Eric said, for running anything but the lightest 120 VAC loads, THAT is a good time to run the generator.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: When to run the genny on voltage read

Reply #4 –
Quote from: Eric Rudolph –
If dry camping and not using any 110 power from inverter, you might just turn it off till you need it.  It draws power all the time. Also if planning to use microwave or other heavy power, turn Generator on rather than use inverter for that load.
Yes, turn off the inverter anytime not using it. Also remember that quasi sine wave inverters will take almost three times as long to cook anything with the microwave as they only see 120V not the 170 volt peaks they need to do it in a hurry. Late sine wave inverters, depending on brand, use .7 amp compared to about 3 amps or more at idle for the old Taytronics that I put in storage.

With only 400ah capacity, we use the microwave every morning to run the microwave to heat the milk and then the espresso/latte maker. Never start the evil generator.

I installed the new sine wave inverter. Will give a review after using it for a while. Also how to change wiring to do away from the microwave or outlet selector switch.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: When to run the genny on voltage read

Reply #5 –
So if my gen is on, the inverter should be turned off, not left on standby.
And if I'm running off of the batteries and not using any AC voltage my inverter should be off
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: When to run the genny on voltage read

Reply #6 –
Quote from: Lt403 –
So if my gen is on, the inverter should be turned off, not left on standby.
And if I'm running off of the batteries and not using any AC voltage my inverter should be off

With generator running OR shore power, it doesn't matter if the inverter is on or off-- it will do EXACTLY the same thing.

It will charge the batteries (yes, if an inverter/CHARGER).  And the generator or shore power will provide 120 VAC to all circuits.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: When to run the genny on voltage read

Reply #7 –
Quote from: Lt403 –
So if my gen is on, the inverter should be turned off, not left on standby.
And if I'm running off of the batteries and not using any AC voltage my inverter should be off
Yes, unless you have a residential fridge with the battery capacity and high inverter efficiency to run overnight, turn your inverter off when you stop watching TV, microwave, etc. The less percentage you use from the batteries, the longer they will last. New tech batteries may be exempt. Some new inverters double as chargers so they can be left on while on shore or generator power but make sure yours does.

As Brett says above, with shore or generator on, it makes no difference. What does make a difference is developing the habit of turning the inverter off. If you always do without exception, you won't forget and discharge or damage your house batteries.


Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: When to run the genny on voltage read

Reply #8 –
I didn't use the invertor the entire 5 days. It's always off as I have the original 2500 with a remote panel.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: When to run the genny on voltage read

Reply #9 –
If you invest in newer batteries they normally require a battery temp controlled charging system.  In late 97 Foretravel started using hearts with serial numbers over 100,000 that could have that capabilities. 

The hearts internal connections, think points, wear and reduce the amount of current that can go to the batteries.

You may not notice as much as you have 2 house batteries.  The 97 went to three.

Our worn Heart outputted 70 Amps.  Replacement magnum 2812 puts out 108 amps at bulk.

You seem to have gotten a lot of "good" out of the freedom 25.

The boards get dust covered inside and the wiring connections loosen up also
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: When to run the genny on voltage read

Reply #10 –
I have 4, 6 volt batteries. The old Heart is working fine. I'm going to leave it for now. Amazing quality and I love the remote panel
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: When to run the genny on voltage read

Reply #11 –
Does your coach not have the generator auto start feature? If it has and it is switched to auto, it will start at 12.2 volts and run for 4 hours to charge the batteries. 
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

Life is made to enjoy, the Foretravel helps!

Re: When to run the genny on voltage read

Reply #12 –
50% discharge is considered the max for longer battery life.

The batteries were never 13.4 resting volts. 

Fully charged is 12.75 or so.

Surface charge fresh off the charger might show higher but it's not useable.

Finding your batteries actual capacity will allow you to know when you are 50% discharged.

If your 24 hour resting voltage is less than 12.75 they are worn.  Not unexpected.

Your 4 6 volts have roughly 400/450 amp hours new.  So 50% is 200/225.

New.  If you use 200 and the battery voltage not under use is less than 12.2 or so they have lost capacity.

Dry camping is a learning experience.  Plus learning your coaches real condition and capacities is necessary.

As I said 97's went to 50% more batteries. 

Condition is the key. Plus good cables and good contacts in the system.

"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: When to run the genny on voltage read

Reply #13 –
I'll unplug it for 24 hours and see what they do. 2 years old. So it  sounds like my range is 12.75 to 12.2 on a healthy battery bank?
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: When to run the genny on voltage read

Reply #14 –
Quote from: dans96u295ft –
I'll unplug it for 24 hours and see what they do. 2 years old. So it  sounds like my range is 12.75 to 12.2 on a healthy battery bank?

Yes.

Anything above 12.75 or 12.8 is just surface charge and will dissipate quickly with just a small load-- a couple of 12 VDC lights for a short time.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020