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oldjohnt

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Posts posted by oldjohnt

  1. 24 minutes ago, hemsteadc said:

    Lots of folks ask about running air with generators, but I've found very few actually do it.

    I dry camp often and ONLY AND RARELY if its EXTREMELY HOT maybe late in the afternoon for brief periods (brief cool down) HAVE USED MY CUMMINS ONAN GENSET TO POWER MY AC

    Good point, I agree X2, have a good one

    John T

  2. Tule, great question here's one retired electrical engineers response:

    1) Its not so much ONLY how big a genset needs to be for running two typical rooftop AC's,, IT HAS TO BE BIG ENOUGH TO START A SECOND AC WHEN THE FIRST IS RUNNING as the initial current surge when starting a compressor may be 3 to 6 times its normal running current !!!! The advertised CONTINUOUS POWER on Gensets isn't the same as SURGE RATING and when starting there is an initial much higher temporary surge current !!!!!! 

    SUGGESTION add a Soft Start on BOTH AC units

    2) If the full load running current on BOTH AC's was for an example in the 24 to 25 Amp Range AND BOTH HAD SOFT START to lower start up current surge (and no other loads running) as small as a 3500 to 3800 Watt Genset may possibly ?? get you by while Id prefer larger, maybe 4000 or more watts.

    3) Speaking of adapters, realize a 50 amp RV with two AC's and a 3 Pole 4 Wire Grounding  NEMA 14-50P Plug,, likely has one AC running on one leg L1 of 120 VAC and the other on the other leg L2 of 120 VAC. ALSO L1 is likely 180 out of phase with L2 so Neutral currents balance each other out...

    SUGGESTION if you want plugging into the genset to be the same as a 50 Amp RV pedestal NO ADAPTERS NEEDED the Genset needs to be a full true 120/240 VAC Single Phase Three Wire with a NEMA 14-50R Receptacle (same as 50 Amp RV pedestal power)

    CAUTION if you use some ?? sort 30 Amp adapters, make sure if you're running two AC's the Neutral conductor isnt over loaded !!! NOTE  a 30 Amp 3 Pole 4 Wire Grounding Plug or receptacle, same as 50 amp, can (subject to source configuration and wiring) use two legs of 120 VAC out of phase with each other in which case Neutrals cancel each other, no problem. 

    BOTTOM LINE SUGGESTIONS

    If available and you want to be able to use the genset same as RV park pedestal and run two AC's with no adapters or phase or overloaded Neutral concerns GET A TRUE 120/240 VOLT SINGLE PHASE THREE WIRE GENSET (has two legs of 120 each 180 out of phase with other) WITH A NEMA 14-50R 3 Pole 4 Wire Grounding Receptacle (same as RV pedestal)  

    HOWEVER sure proper and adequate adapters or other plugs and receptacles can be used provided configured and wired correctly, AND PROVIDED NEUTRAL CONDUCTORS ARENT OVERLOADED.

    I have a Cummins Onan Genset that's great, but believe Yamaha and Honda are good quality brands, some are well satisfied with Predator or Champion THIS IS YOUR CHOICE 

    I recommend an absolute minimum of 3500 Watts (if full true 120/240 L1 180 out of phase with L2) BUT ACTUALY PREFER BIGGER, say 4000 or more Watts 

    I recommend a Soft Start on both AC's

    Best wishes, do your homework, choose wisely and post back any further questions..Im sure I missed some things so hopefully the other fine sparky gents can add more to this......

    John T Live in the RV dry camped at Juniper Springs Florida

  3. 25 minutes ago, GlennWest said:

    Victron doesn't sell 48v batteries. 

    If so that doesn't surprise me one bit, I'm not aware of Victron batteries 12 or 48 Volt ??? The ones that failed in the OP were Battleborn not Victron. A quick Google search does make it appear several companies indeed manufacture 48 Volt LiFePo4 batteries, take your pick lol  

    48 volt lithium iron phosphate battery - Bing images

    Best wishes to all here

    John T  FREE dry camped near Wildwood Florida, gotta love Solar and Lithium yayyyyyyyyyyy

  4. On 3/15/2023 at 6:57 PM, GlennWest said:

    Better to buy a 48v battery then if this is true

    I agree, iffffffffffffffffff your preferred battery manufacturer makes a 48 Volt battery ???? it saves allllllllllllllll those series connections with their potential problems, balance problems, and any in series multiple BMS issues. Now if you have a suitable 48 Volt Inverter/Charger,,,,,,,,,,,,An MPPT 48 volt charger for your solar,,,,,,,,,,,,,A 48 to 12 DC to DC converter for any 12 VDC loads YOURE GOOD TO GO..........  Im NOT a fan of multiple series connections and more than necessary electronic components, but sure higher voltage has its advantages especially for high energy users. To each THEIR own, no necessarily right or wrong answers on this.

    John T  NOT any solar expert NO Warranty lol

  5.  

     

    On 3/11/2023 at 8:08 PM, Ray,IN said:

    Does that sound reasonable?

       Hi Neighbor Ray, when it comes to very specific charge settings I advise people to consult with the battery manufacturer as different makers can have different preferences and after all its they who offer the warranty !!! Ive had some AGM that specified something like 14.4 BULK Charge then 13.6 for ABSORPTION then 13.2 for FLOAT I forget what brand that was ?? 

     What you say may well be REASONABLE  ??? The 14.8 sounds high (especially if Absorption) than some others Ive seen ..Do you have THREE Stage capability charge settings ??? Bulk, Absorption, Float or only two??

     John T   Best ask the battery maker nottttttttttttttttt me...  Maybe someone who has knowledge or experience with your same batteries can help ??? 

     

     John T

  6. 59 minutes ago, slockfox said:

    The old fabric was 14 wide but i had to order a 15 because they measure from rail to rail for some reason.

    I had a similar experience (sort of the opposite, had to order a SO CALLED 14 foot instead of a 15) when I ordered a replacement A&E fabric from an RV dealer. I gave them the Model Number,,,,,,,The Serial Number,,,,,,,,,Measured the actual width gave them that.................

    Fabric arrived DIDNT FIT it was too wide they had to reorder one a foot narrower HOWEVER they tried to blame ME who gave them Model Number, Serial Number, Actual width grrrrrrrrrrrrrrrrrrrrrrr

    Once I locate the fabric correctly so when rolled up the arms they fit exactly, I lock the fabric in place so it cant slide top or bottom........... 

    John T Currently near Apopka Florida

  7.   Good information, thanks for posting !!!!!!!!!! My thought are as follows:

       Having been a power distribution engineer and RVer of 50 years over much of the USA, IVE SEEN IT ALL OUT THERE. The thing is REGARDLESS of any NEC, which some states or some jurisdictions may or  may not have adopted..  NOTE no matter what the NFPA has published or perhaps the STATE may or may not say, many many counties especially rural have not adopted the requirements or enforce them or even have inspectors or exercise any authority grrrrrrrrrrrrrrrr  ,,,,,,,,,REGARDLESS if codes have changed as older installations can still be GRANDFATHERED IN,,,,,,,,    Many Many especially OLDER RV parks and due to the ever increasing energy demands of newer bigger RV's HAVE INADEQUATE ELECTRICAL DISTRIBUTION. 

     On a hot day with 50 Amp RV's running AC's, if you're located far from the last distribution panel VOLTAGE MAY BE LOW which can cause overheating and damage to RV appliances grrrrrrrrrrr. One other thing Ive observed is inadequate electrical service to a park from the utility. Its more expensive to provide more transformers and services into a park. Also many older parks had adequate electrical service 20 YEARS AGO but now with 50 Amp RV's and lots f AC running THEY CAN NO LONGER KEEP UP and upgrades now are very expensive.......

     Ive seen parks that supply 208  Y 120 Volt Three Phase Four Wire which is fine if properly installed and balanced but, of course does NOT provide 240

     SOLUTIONS sorry but I don't expect things to improve drastically in the short run as its so expensive to upgrade PLUS as noted above theres a shortage of code enforcement and/or older grandfathered in parks which are reluctant to upgrade......

     One old retired engineer and long time RVers advice is to utilize surge protection and energy management systems, check BEFORE plugging in especially on hot days when parks are full...Remember there's no V = I x R Voltage Drop UNLESS THERES CURRENT DRAW    Early or before AC's are running a voltage check may be fine BUT LATER ???????? Thats when you need to check pedestal voltage.

     Best wishes and God Bless all here, thanks for an informative thread which may bore non sparkies lol THANKS to all here for the help you have given me !!!!

    John T   BSEE,JD  Still dry camped near Lake Wales in sunny Florida, gotta love solar and lithium batteries

  8. 1 hour ago, Wrknrvr said:

    I forgot about 208 voltage.

    I specified a ton of 208 Y 120 Volt Three Phase Four Wire services in applications where the bulk of the load was 120 VAC Single Phase Convenience and Lighting (like an office) NEVER heavy industrial. If the HVAC was relatively low I used 208 Volt Three Phase for that alone. I also used a lot of 277 Volt Single Phase.

     John T

  9. 5 hours ago, Lou Schneider said:

    Too bad the video is now unavailable - someone made it private.  Too graphic?

    Yo Lou, you would have enjoyed it........ I didn't try again today, watched it yesterday and the day before ?????? It didn't look good for BB, maybe there was a complaint ??????? As I posted above it may NOT have been all BB fault however

    John T

  10.   Thanks for your thoughts Wrknrvr, glad you filled out that blank page lol. My years of experience in the electrical power industry bears up what you say. Line Voltage Drop becomes more n more a factor and more n more critical as loads increase especially in the heat of the day WELL DUH lol The same holds true on the HV primary grid as well as the LV secondary. The father from the substation the lower the voltage during times of high current in which case supply transformers may use different taps. Unfortunately on the LV end user side long runs and high loads yielded low voltages at the far end of the plant !!!!!!! Sounds like you had some fine instructors, I did likewise at NEC Seminars taught by the likes of Joe McPartland (EC&M Magazine) and Mike Holt.

     As far as motors and their design, my first Electrical Engineering job was with the Century Electric Motor Company where I learned how designs changed over the years from when they were (seemed to me at the time, no guarantee) heavier, perhaps more iron and magnetic material, more copper versus when market factors and economics perhaps caused changes. I remember the big huge heavy Repulsion Start Induction Run motors !!! Now those would start high torque loads with ease lol 

     Other factors I observed over the years was how the utility supplier (perhaps to save money ??) provided less service transformers at a location, maybe the customer used 208 (got him by in certain situations) instead of 240. Earlier days the utility may have furnished 480, 120/240, as well as 208Y 120 however later they ONLY provided 480 and the customer had to supply his own dry transformers for other voltage requirements ...  

     One last note, earlier industry used a lot of UNgrounded Floating Delta (for their good reason at the time) while later Grounded systems came in favor.......

    Thanks again Wrknrvr and all the fine gents here who contributed to this informative thread, I hope we helped the PO at the risk of boring non sparky or non power lovers lol

    Best wishes and God Bless all here, love this Forum and helping anytime I can

    John T   BSEE,JD

  11. 17 hours ago, Wrknrvr said:

    Can I post a blank answer.

     

     

      As in a nice clean thoughts.   To many other things to be thinking of at this time.

    Good Morning Wrknrvr, I look forward to ANY answer (or blank lol)  you submit. I appreciate and have learned from your many technical postings and am glad to help my fellow RVers anytime I can. There are a fine bunch of gentlemen on here, lay as well as professional, all willing to help yayyyyyyyyyyy God Bless em all

    Thanks for sharing your experience and all your help, I hope to hear from you soon my sparky friend....  

    John T  Still dry camped East of Lake Wales FL

  12.   Yo Glenn, I just watched the video for the second time and according to it there was a Battle Born Battery Failure and he also indicated Battle Born was replacing all eight batteries WOWWWWWWWW talk about good service. QUESTION Does Victron make those batteries for Battle Born ??????  I ask as you speak of Victron batteries and Victron replacing them ??

    2 hours ago, palmeris said:

    Battle Born does indicate that these packs can be series , not to exceed 48volts, that each pack must be at full state of charge prior to connecting them in series for proper balance , and to disconnect and charge them individually to full SOC annually. His comment that they had been running fine for over a year tends to make me think the maintenance routine wasnt followed.  Maybe the cause, maybe not 

        palmeris, Good point and it was ALWAYS that same location (third in series string) where the battery read 17 volts (even with different batteries placed there) yet the other three read 13 volts ????????? Whether or not he failed to follow Battle Borns directions regarding charging balance and annual maintenance I HAVE NO IDEA ?????? I hope Battle Born lets us know.

    FWIW one pure guess. Regular (NON BMS) batteries in series receive the same charging amps HOWEVER the Battel Borns EACH have an EMS which looks at the terminal voltage and delivers charging amps accordingly, with four in series and each its own BMS perhaps there could be balance problems and why one failed ?????????????????? What say you ??

     John T   Though long retired still an ever curious engineer and proud of it 

  13. Glenn, yep there are several of those Battle Born units out there. It's strange how ONLY that the third battery in a series string of four used to make up 48 Volts WAS THE MAIN PROBLEM AND FAILED BIG TIME. He indicated THAT BATTERY was reading MUCH HIGHER voltage (wasnt it 17 volts?) then the other three in series that were near 13 volts each. I dont know how THAT battereis BMS allowed such ???????? Hope BB figures it out, I didnt notice it to be any Victron failure ???

    Stay tuned

    John T 

  14. On 3/8/2023 at 10:32 AM, Dutch_12078 said:

    John is correct of course, so I'll just note that nearly all standard residential panels like the Square D in our RV are equipped for easy conversion from a bonded neutral/ground to isolated neutral and ground by simply lifting or removing a bonding strap.

      Thanks Dutch, good note, yep that big crossover BONDING bar (from Neutral Buss over to Ground Buss) you spoke of is soooooooo obvious out in the open and easy to install where the typical home Main Panel provides the first disconnect means and likewise soooooooo easy to remove (two screws) when the panel is configured as a Sub Panel. As you well know some (maybe cheaper??) service panels use a single common buss bar where BOTH Neutrals and Grounds attach.  I was never a fan their use in all my years of practice...

     Its a pleasure sparky chatting with you gentlemen even if we may bore some other non techy types lol

     Best wishes and God Bless yall

     John T Live in the RV dry camped at Lake Rosalie, Lake Wales Florida,,,,,, its hottttttttttt here

  15. TH, the problem is while indeed a pressure accumulator works, IT WOULD TAKE ONE HUGE VOLUME ACCUMULATOR to produce any long term help and if the parks pressure is low to start with that's not a solution either. One park I stay in has water outages now n then and/or occasional low pressure, so I keep my fresh water tanks filled and my 55 PSI pump and small onboard accumulator get me by fine.

    John T  Retired Engineer NOT a Plumber so see what those professional have to say

  16. Glenn, I actually saw that You Tube video LAST NIGHT !!!!! For sure that Battleborn Battery suffered one catastrophic failure I hope they determine the cause. I thought at one time BB (or some other maker) DID NOT APPROVE SERIES CONNECTIONS and the failure noted did involve a series 48 volt connection of four BB's ????????????? Interesting video for this engineer........

     

    John T  Retired but still ever curious EE

  17. 15 hours ago, 57becky said:

    I was so glad the 110/220 was finally addressed in this thread

      Its hard to believe it but Ive heard MANY MANY even long time RVers and MANY farmers (NOT professional electricians or electrical engineers) and lay people still call it HUNDRED AND TEN. I was at a farmers place who told me I could hook up my RV to what he said WAS TWO TWENTY. Of course I checked it out, he had a NEMA TT-30R 125 Volt 30 Amp Receptacle, which turns out was wired right for 120 VAC WHEW LOL 

     Way back in EE school at Purdue we studied the history of power distribution includuing the battle among Edison's DC versus Westinghouse (if I recall correct??) and Tesla AC  while the answer seems soooooooooo obvioius now. Had Edison only invented a DC Transformer wink wink lol

    15 hours ago, 57becky said:

    I'm a retired utility lineman and this has always been a problem.

      Bet that was a rewarding career, most of my engineering career involved secondary distribution although I did some design on our 12470 Y 7200 HV Distribution. I was impressed by all the safety procedures linemen used, an accident was never heard of in all my years  

     Hey many many non professionals still call it HUNDRED AND TEN and I don't see that changing anyway soon, but hey I don't know all the proper names/use when it comes to plumbing or HVAC or carpentry either !!!!!!!!

    John T Another retired sparky

  18.   For the non sparkies here, one other MAJOR difference in an RV Panel versus "many" typical home panels is THE RV PANEL IS CONFIGURED AND WIRED WITH SEPERATE INSULATED AND ISOLATED NEUTRAL AND GROUND BUSSES (its treated as a Sub Panel) unlike "many" home panels where Neutral and Ground are bonded !!!!!!!!!!!!

      I likewise prefer "standard" Square D or GE etc. panels in an RV (when possible) as if anything is labeled for RV its more expensive PLUS maybe oddball or different style grrrrrrrrrrr  

     Nice sparky chatting. hope this helps, post back any questions...

     John T

  19. 2 hours ago, Kirk W said:

    I am assuming that you mean none were in the stick houses?

    You assumption is certainly CORRECT. I have added my own NEMA TT-30R Receptacles in carports or garages etc for my RV's over the years. If my daughter ever decided to drive her Tesla from Texas to our Indiana home Id probably add a NEMA 14-50R for her benefit or my own for a 50 Amp RV if I were to get one. Her Tesla doesn't plug direct into a 14-50R but that was used to power up her Tesla level 2 charger as I recall last time I was there. 

    As always nice sparky chatting with you

    John T

  20. 19 hours ago, Payroll Person said:

    Tt10-30 is simply misunderstood by most

    I agree X2, Ive even heard some think or call them 220 !!

    The NEMA TT-30 R is a 125 Volt 30 Amp 2 Pole 3 Wire Grounding Receptacle used by 30 Amp RV's. Their power cord has a NEMA TT-30 P Straight Blade Plug on its end. I have owned several homes and NEVER saw any of those in use HOWEVER I have seen NEMA 14-30R 125/250 Volt 30 Amp 3 Pole 4 Wire Receptacles in use.

    As far as EV charging, I have seen NEMA 14-50R 125/250 Volt 50 Amp 3 Pole 4 Wire Grounding Receptacles in use which is the same as used by 50 Amp RV's.

    Be safe everyone

    John TNEMATT-30R.jpg.a77d6397cd18120052cbf407971b7e64.jpg

    NEMA 14-50R.jpg

    NEMA TT-30P.jpg

  21. 49 minutes ago, GeorgiaHybrid said:

    Forgot to add, oldjohnt probably remembers DC power distribution back when he was working with Thomas Edison😁😁😁

    Grrrrrrrrr lol Yep and I was on Edisons side but lost out to the upstarts and likes of Tesla and Westinghouse lol.. Seriously I once considered joining the Tesla Society he was a genius and ahead of his time but that wireless AC power distribution scheme didn't prove out.

    PS you would be surprised at how many older farmers (maybe even a few RVers) think and call the standard 30 Amp RV receptacles as 220 !!!!!!!!!!

    John T  An oldddddddd sparky indeed ................  

  22. 11 hours ago, shippreck said:

    Actually, The way you stated it is incorrect.  In phase you have 110.  Out of phase, you have 220.  All you need do is connect one leg of the 220 input to both legs of the RV power plug and then use the neutral for both circuits. 

    And to add yet even MORE information lol: In true 120 240 Volt Single Phase Three Wire Service L1 and L2 are 180 out of phase with each other, when one is + 120 the other is - 120 so its 240 across the two !!!!!!!!!!!

    If you were to use/connect ONLY ONE leg of 120/240 single phase three wire service over onto BOTH hot terminals (L1 & L2) on a NEMA 14-50R Receptacle A VOLT METER ACROSS THE TWO HOT TERMINALS (really the same feed) WOULD READ ZERO VOLTS POTENTIAL DIFFERENCE,,,,,,,A METER ACROSS         EITHER          TO NEUTRAL WOULD READ 120 VOLTS..

    If you use a dogbone connector to convert 30 Amp NEMA TT-30 over to a 50 Amp NEMA 14-50 R Receptacle for powering a 50 Amp RV, it simply connects BOTH legs (in the 50 Amp outlet) to the single available leg of 120 VAC available in the 30 Amp receptacle. AS CORRECTLY noted above, in that case the current carried by the Neutral IS THE SUM OF CURRENTS ON BOTH LEGS. Thats UNLIKE a true 120/240 Volt service connected to a 14-50 in which case the Neutral currents (being 180 out of phase) cancel each other IE if 20 on both legs the Neutral current is zero.

     If you have a 50 Amp RV and use an adapter to power it via a 30 Amp receptacle BE AWARE THERES ONLY 30 AVAILABLE AMPS AND A 30 AMP RATED NEUTRAL !!!!!!!!!!!!

     Hope this helps, best wishes

    John T Live in the RV at Pioneer Festival in warm n sunny Zolfo Springs Florida

     

  23. 6 hours ago, Chad Heiser said:

    This system is not cheap.  Retail it is around $25 to 30K (depending on the specific components and the time involved in the installation)

    HOWEVER with your relative high energy requirements your system is much bigger than many people would ever need, so of course, that's gonna cost more. As solar prices keep dropping and technology improves the cost benefit and amortization gets better all the time. For a more reasonable perhaps $2K to $5K a modest energy user can become energy independent. 

     As we often preach when someone asks how much solar and batteries he needs PERFORM AN ENERGY AUDIT first.

     Thanks for the cost figures and I hope they don't scare off those with lower energy requirements.

     John T

     

  24. CONGRATULATIONS and thanks for the detailed update Chad, it may bore some but for this old engineer I TRULY ENJOYED YOUR POST.

     I only have a 29 Ft Class C and don't require near your energy HOWEVER I upgraded to Solar and Lithium batteries AM HAPPY AND NEVER LOOKING BACK. Sure it requires a substantial initial investment (and is NOT for everyone) but the freedom to dry camp anywhere for indefinite time at little to no cost makes it worthwhile to me at least.  UNLESS its rainy n cloudy for days on end, like you I can dry camp almost indefinitely (like if I were plugged in) WITHOUT ever firing up my genset. I also added a DC to DC charger so when driving in cloudy or rainy days I can top off my lithium batteries.   

     I took a different route as far as black tank and being able to go long periods before having to dump. I use a Thetford Electra Magic 80 Marine Recirculating Toilet which enables the two of us to go almost two weeks before having to dump.  

     GREAT SYSTEM, gotta love Solar, thanks for sharing, you are an inspiration to those who may be considering upgrades !!! As always, nice sparky chatting with you  

     John T Long retired Electrical Engineer but love this sparky chat and love Solar

     

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