you may have a b.i.r.d. device that un-isolates both batts whenever 1) shore or genset are charging, or 2) when the alternator is charging. it may have failed or maybe one of its 5 or so connectors came loose.
seems like after a good 24 hr charge via parallax converter, i unplug shore and toggle house disconnect to STORE. batteries' voltage after a few hours settle in the 12.5-12.6 range. so i disconnect house ground cable and soon hear a clunk. in a few minutes, chassis bat is a happy high 12.68 and rhe house a cozy 12.75.
5 yrs ago i replaced the chassis/house isolator solenoid, but i think it never changed a thing. i am suspicious that the B.I.R.D. gatekeeper is not adhering to its 13.3 v thresholds, and never has. or else trail lite miswired something.
if i knew where the bird is, i might figure a way to test it.
i think my house and chassis batts stay in parallel more than the isolator solenoid and bidirectional isolator relay delay device are supposed to keep them after a charge.
i am thinking to put a terminal disconnect knob/switch gadget on the positive terminal of my house batt.
i would use it to disconnect the house batt after charging via shore or genset. i will monitor voltages in both batts to determine a good frequency and length of charge.
i was wondering if this would have any bad impact on the house batt disconnect solenoid and its STORE/USE toggle, or any detrimental impact on the chassis/house batt isolator solenoid and its B.I.R.D. controller.
CA, the previous solenoid pic was from 2011 when i was already wondering about a fluxing voltage field of the two batts. i was urged to replace the isolator solenoid. this is the completed replacement today. there was no notable difference before/after switch.
i listed several 'as it should be' things in attempting a clear picture of state of switches when i observe 2 weird results:
1) engine alternator charging chassis batt alone handles house DC, and
2) the spooky 5 sec where non-charging chassis batt could nevertheless power house DC
Chris' explanation makes perfect sense w/r my BIRD setup
but it is things like 2) that i detect w/ my voltmeter, and as MEXICO says, causes my hail to fall out.
i am gonna just stop taking readings, i think. i know that posts of such results is a real turn-off.
i hope there are clues in this morning's troubleshoot results - i think they will tell someone here right off what is up...
* i disconnected house batt cables
* measure NO voltage between positive and megative cables
* try to toggle house disconnect to USE, and nothing
* crank engine and disconnected house batt cables read 14+ volts
* house batt is still disconnected
* engine still running
* toggle house batt disconnect to USE, and red lite comes on
--- and house lights work
--- genset primer works (audible click)
--- house LED battery meter reads 4/4
so in this condition, there is no need for a house battery
* turn house disconnect to STORE and red lite goes out
" turn off engine
* walk dogs 30 min
* engine off and house batt still uncabled
* toggle house disconnect to USE and red lite comes on
* turn 3 hall lights on and they work about 5 sec then go off (along w/ red lite, i think}
i've found over the years that the BIRD device is not discussed much on these or other rv forums, but as far as i understand, it is used in many motorhomes.
to those who understand the innards of electronic gadgets, can i just assume the BIRD device seldom fails to do its gatekeeping duties and just forget about it, much as we take for granted something like spark plugs?
for those with motorhomes that have B.I.R.D.s, do you find that you get inaccurate or misleading voltage readings from your house battery and your chassis battery. for instance, readings that differ and fluctuate at odd rates depending on house battery disconnect toggle (STORE/USE}.
i have attempted to express some weird things i seem to encounter when doing so on this thread from the C forum. as confused as i seem here, a few years ago i went through similar issues before i'd ever hears of BIRD. to my great relief, another trail lite owner discovered we both had one in our rigs.
at this point, i am resigned to just try to ignore voltage readings and simply try to make it a point to give batteries ample shore power charge time from the parallax 7300 between RV outings.
but it would be somewhat of a relief to hear from others that a) i am not imagining things, b) i need to expect unique voltage sharing/interaction w/ the BIRD relay/delay and chassis isolator solenoid, and/or c) my system has a problem that can be tested by doing X.
i thank you for any insights and clarity.
i think the walmart tender is schumacher. they also have a battery tester for $35, but i am not sure how to use it, especially w/ the 'entanglement' posed by the BIRD.
i guess i would put the tender on either battery, 'cuz they will both start charging and somehow share the 1.5 amp trickle.
what intrigued me was how i stumbled onto this
with house batt ground terminal off, crank engine, turn house toggle to ON, and engine lights up house things.
this seems to say you do not need a house battery at all.
Since you are always plugged in I would not change a thing. Do keep the batteries charged when not in use.
many thanks to all who have posted, and a big apology for my confused posts. i just cannot seem to get consistent and/or expected voltages from the two 'separate' batts (house and chassis), and i know it has been an issue probably from day one. my gut says my inconsistent changes in voltage readings is all about the B.I.R.D., and if i knew where mine is, i think i would change it.
but along the lines of smketter's comment, everything pretty much works as it should, and adopting a routine of more frequent and longer shore charging while not in use seems like a practical plan.
thanks again to you all - i truly value ypur help (and patience).
several posters were describing the need on some rigs to plug generator into coach for OP, so i did not.
lf unaware that it is setup that way, you would never think of it.
mine has automatic transfer. a couple years back, as a 7 yr RV veteran, i tried to help a recently widowed friend get her 2007 four winds generator to power stuff once started. i gave up, came home, and came to these forums overnite and called her the next day with the news.
i think it is a pretty reasonable idea...it forces the owner to recognize that AC comes only from a big powerline: shore or genset. no powerline, no AC. thus, the owner also learns what a house battery can and can not work. i think OP could thus have more quickly realized why the microwave was also not working.
when he said this, i was going to post and note which other things he ought to test that were likewise not DC, so that air-conditioner could be ruled out and a focus on genset was needed.
but a good lesson is learned.
with house disconnect toggled to STORE (OFF), i disconnect house batt's ground wire and read 12.8v between wire and battery ground terminal. is this proper? shouldn't there be no voltage?
with house batt ground terminal off, crank engine, turn house toggle to ON, and engine lights up house things.
wondering if emergency solenoid is sticking, i crank engine toggling ES on dash, and no longer read voltage between house batt grund terminal and ground cable... but, not sure if some BIRD time delay is the cause.
i feel that maybe i am seriously handicapping my novice-level electricity monitoring with my pocket multimeter from radio shack
which a former electrician adult student recommended 15 years back in my teaching days. i also have an old banged-up-a-bit exide trickle charger and a walmart everstart 50/10/2 amp charger. i got these to monitor our small old 40 hp outboard dual cycle boat battery. (now with a sole 5.5 y/o walmart everstart happily reating at 12.7 v w/ only monthly 4 hr trickle-ups).
ls there an easy to read, pretty simple meter that would give me amp readings and some reliable indication of the state-of-charge of a battery? maybe load test too? simple and easy to see are important.
quote from OP: "charged both batts for 12 hours (all day thursday 5/14). readings start out as 13.3 house, 13.0 chassis and at end of day, both read 13.78 w/parallax on, and 12.75 when off.
12 hours later, house is 12.66 and chassis is 12.70. i predict they will be near 12.56 house and 12.50 chassis in a week."
now, 24 hours later, house 12.76, chassis 12.48. i guessed right, but chassis batt did not wait a week to drop to 12.5.
i then turn house disconnect ON, and bam, both house and chassis are 12.76!? i will leave it ON for a day or more and monitor.
cranked engine up, and alternator reads 15.15 in both batts, and drops to 14.7 in a few minutes.
i have often seen this 12.5 chassis reading and been bothered by it.
thanks all for input responses so far...
It's going to take longer than 12 hours to fully
charge your batteries with your converter. I usually plug the batteries in for a few days when we get home, A day long top off charge once a month and then a few days before we go out. At this point your batteries may need some care to get them back up.
the casita trailer group noted that their manual said 8 hours to
charge a battery w/ P 7300.
when i charged 6 days ago, the 1st 8 hrs were w/ RV plugged into shore. next, with battery disconnect on STORE and a separate charger connected to house batt. the BIRD then allowed both batts to trickle and a battery full light came on in 4 hrs.
is it OK to charge both house and chassis via BIRD in this manner -- using external charger w/ BIRD?
as noted, the 1 y/o batteries' dropping from 12.75 to 12.5 in a week
is not making me happy.
i saw no voltage between house ground terminal and ground wire w/ battery disconnect in STORE.
i am reluctant to do same check on chassis batt since it might reset
computer. thoughts on this? is there a 30 min delay before chassis
batt disconnect resets computer?
Hate to say this but that is a terrible
converter/charger. It's charging profile is terrible and the only time it isn't under charging it's over charging.I swapped mine out while it was still perfectly healthy for a Progressive Dynamics because of the superior charging and storage ability.
a lot of people have as reported in dozens of threads i have plowed
thru. but the P 7300 is still in a lot of RVs with happy owners. the
manual says it lowers the amps after charging a while, but maybe at
13.8 volts, which many say is cooking level. but if you put
disconnect on STORE after 12 or 24 hours?
and doesn't a 14 v alternator maybe do same thing?
It sounds like you have regular wet cell batteries
(batteries with liquid acid in them) in your RV.
The voltage level coming from the stock Parallax 73XX converter in
your RV once it has fully charged your batteries - if you then
continue to leave your converter connected to the batteries - is too
high of a level to be kept on regular wet cell batteries continuously.
However, the voltage level coming from your converter will bring
them up to full charge whenever they are low - but just take longer
than other types of equipment designed to put out a higher voltage
level for faster charging. Many RV owners replace the stock
converters that come in their RVs so that the resulting voltages from
their new chargers are better suited to their wet cell batteries for both long term storage and faster charging.
All the above being said, there are different models of dry cell RV
batteries available that do much better with stock RV converters.
We have those kind in our RV and they are many years old with still
most of their capacity left. Our RV sits in the back yard when we're
not using it and with our model of dry batteries, the converter can be
connected to them almost continuously without damaging them.
Hence our batteries are always in full charge whenever we start out
on a trip. Our batteries also charge faster than regular batteries, so
the converter brings them up to around 90 % of full with only a few
hours on our small quiet generator when charging in a campsite.
When traveling between campsites, the main engine alternator (our
RV is a motorhome) will bring our batteries up to full charge in 4-5
hours of travel time. RV converters are not always worthless, even for camping without hookups ... as they do play well with certain types of batteries.
i am OK with a slow charge at home and then disconnect. but i not
sure how long and how often. i think, contrary to what some report,
a whole month is too long. even every 2 weeks may be stretching it.
i think i may have already done some harm to these new batts by
not doing weekly 12 hr chargings.
Costco group 78 is a deep cycle? I think you are
better to just leave it plugged in. Best would be a PD4645
replacement converter charging at 14.4, 13.6 then float at 13.2
group 78 is what chevy uses in lots of vehicles. it has 850 CCA and
side terminals. they are maintenance free from costco.
we are always on shore power at cg, so no need for deep cycle
house batt. i do not think the 850 CCA harms onan, which needs
450 CCA. so having 2 identical maintenance free batts seemed like
a good idea.
Alternator will initially charge at 14.6+ volts and as it heats up with the rest of the engine will drop into the 13.8 to 14.2 zone. This is great for the chassis battery but the house battery is often connected through a relatively long wire isolator etc that will drop voltage a bit and provide a slower charge.
You can get an aftermarket regulator that does a specific 3-stage
charging routine. More popular in the boating world.
Not sure how much off-grid camping you do but also consider 100 to
300 watts of solar instead of the converter upgrade. No more worry
about plugging in.
thanks, i was not sure, but suspected that is how they perform. the
P 7300 seems to work along exact same lines as the alternator.