Battery/load/controller connector

I'm looking for something that I can connect everything together so I don't have a billion wires connected to the first battery. Like a junction... I'm sure they make something like that but I don't know what it is called.
Also I have a couple Trojan 105's that are still good. I'd like to use them as a separate battery bank with some type of in-line switch so that I can charge/use both banks (in case my 4- 12v battery bank runs low)
A switchable junction would be awesome. Any ideas?











3 Kyocera 315W panels,Midnight classic 200 controller
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Comments

  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    What you're thinking about is a common connection point called a bus bar. Basically a heavy bar of highly conductive metal with multiple taps for securing wire lugs to and insulated stand-off mounting.

    As for switches, you can't beat the ones from Blue Sea like this: http://www.solar-electric.com/blseabaswon3.html

    Depending on how many wires of what size you have to bring together you can sometimes make the connections at the switch or the fuse holder. Be sure you have proper fuses/breakers on all these lines.
  • PhotowhitPhotowhit Solar Expert Posts: 5,650 ✭✭✭✭✭
    Re: Battery/load/controller connector

    Well, I'm not sure where your wires are coming from, You can get by with just one if your 4 batteries are in a single string to make a 48 volt battery bank. If your using them 2 strings parralelled for a 24 Volt, or an ugly 4 strings set up you should look into keeping the resistance the same across each battery, and use the same length wire to a bus bar, with a fuse for each on the positive side.

    If you have a single string and assorted wires from CC, inverter, voltage monitor, 12 volt appliances,.. you might look into an E-Panel or DC disconnect box of some sort.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    Blast. Forgot to put the link to the bus bar stuff. http://www.solar-electric.com/brbusbatebus.html
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    Cariboocoot,
    Yep that's what I was looking for.
    My positive leads on the RV vary from very small wires up to battery cables.Some I don't know where they go. Others go to leveling jacks,old school charger/converter,charge controller etc. With all the loads going to the positive post now I can barely get a nut on it! So the Insulated Terminal Bus Bar-long for all the loads connected
    to the BS-9001E common (with 0 gauge?) then battery bank 1 positive to #1 and battery bank 2 to #2 will do what I want?
    Can I connect all negatives to a ground buss bar or do I need to isolate the two battery bank negatives?
    I'm currently using #4 equal length cables in the battery banks which I assume should be larger wires but o.k. for now?
    I'm in float mode by 1PM so it seems I'm not having much of an issue there.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    The negatives can be common. The positives (assuming this is two parallel batteries for the same system and not house/motor battery set up) can go to the same positive bar, but each should have its own fuse on it according to how much current is expected. '0' or 1/0 wire is good for 150 Amps (up to 200 momentarily) so the fuse has to be lower than that. Sizing is a bit tricky as you don't really know what any of that stuff is. Scary! Ideally each of those positive feeds going to wherever should have a fuse/breaker right there at the power source.

    Whether or not the existing wire sizes are adequate is impossible to tell. But if you can provide circuit protection according to the wire size at the power source you will greatly reduce the risk of things going up in flames due to over-current. In other words any piece of 10 AWG coming off the positive should have a 50 Amp fuse/breaker on it since it's good for 30 Amps continuous.

    Don't you just hate automotive wiring? RV's are the worst! Especially if someone else has had their hands on it.
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Battery/load/controller connector

    Don't you just hate automotive wiring?
    My wife's minivan has a constant 4.3A drain on the battery with everything turned off. I have pulled every fuse in both fuseboxes one by one looking for the leak, and none have affected it. PITA Royale.
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    Thanks for the info.
    The large positive load wires go to the RV converter in the back.Those have black blocks on the lines which I assume are fusible links. I'm going to try to trace the small ones but I'm guessing they go to a fuse next as who ever did wiring since '83 knew what he was doing.Everything I've checked so far has been done correctly.
    I disconnected the leveling jack cable since I won't be needing it any time soon.
    I'm working on figuring out that converter.I want to disconnect the built-in charger since it doesn't appear to be working.(I think I may have blown it plugging shore to inverter). I want to plug my shore power line in to my pure wave 1500w inverter so I don't want it running power to charge itself.
    I'd like to get all my AC outlets working but still have the genset generator able to power them as well.
    I've got the switch & buss bars in my cart at NAS&W but I'm waiting on those Trojan's to charge.I've been charging them for hours but they are still at 1200 specific gravity but register 12.75V so maybe those aren't any good.(?)
    I was thinking about getting two new ones for a second battery bank. (Neither bank using motor battery) My current bank is 4 cheap walmart 12v deep cycle 110aH batteries in parallel. Since they are new I really don't want to waste them.When they die I'll get around four 6v Trojans as replacements.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    If you've got a charge on the batteries and it is showing current going to them and this has been connected for hours with no decrease in current/increase in Voltage something is wrong.
    SG of 1.200 isn't dead, but it isn't charged either. Perhaps your charger can't put out enough current for the batteries? Try charging one at a time instead of all together.

    What are you using for an inverter? I ask because installing an inverter-charge eliminates the troubles with the RV converter. Trying to retain the latter and use it as a battery charger is a wasted effort. Especially considering how easy it is to get the wiring screwed up! You have got to be able to disconnect the inverter's AC OUT whenever generator or shore power is used to supply AC. This must be fool-proof or something will go poof.

    Anecdote time! Waaaay back when I was young and RV's had first been invented (the engines were rated in dinosaur power) my Uncle George had one. He made a tiny little mistake with the AC wiring and back-fed the shore power to the generator output. It took me two days to replace the traces on the generator's regulator board and install a center off switch for the AC source (it had none; you were supposed to know to switch off the gen's output before connecting the shore feed. WHOOPS!)

    So you see, it isn't anything new. :D
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    I'll try that on the batteries.
    The inverter is a cheap "tigers claw" 1500w/3000w peak.No charger. I have a progressive dynamics PD764Q power converter. It has an automatic relay so it switches when generator/shore power is used. I don't need much for charging.I have a little 10A charger which works well.
    On the converter I just want to disconnect the built-in battery charger just in case it is working to avoid wasting power.
    I'm not sure what happen to the charger in the converter.It did work fine (though it is pretty worthless due to it's low output).I don't see how the 1500w inverter running off the battery with the shore plugged into it could have blown anything as it would be the same as plugged in at any 120v source.I did mess with a couple wires on the converter.I ran a different 12v wire thru one fuse which had an orange wire hooked to it originally. The orange wire labeled optional tv antenna on the DC side & blew fuses instantly so I removed it.
    There was a smaller wire added to the DC battery + connection (small connection hole/no room for extras) that I also moved over to the fused line. I tried moving it back with generator on and it made no difference. I had moved the converter around a bit so maybe something came loose though I didn't see anything.Could just be the led light out...I'll have to see if it has output. Everything else on the converter works fine though a little 425w inverter wired in on the DC side chirps under a fair load like maybe a weak ground(?)
    So do you think I need to instal a inverter-charge?
    "Waaaay back when I was young and RV's had first been invented" lol Mine is a 1983 Pace Arrow...that's pretty way back. The fuel door says "Ethel" only! (just kidding)
  • CATravelerCATraveler Solar Expert Posts: 98 ✭✭✭✭
    Re: Battery/load/controller connector
    Don't you just hate automotive wiring? RV's are the worst! Especially if someone else has had their hands on it.
    It's way beyond that as a RV is both automotive wiring and RV mfg wiring! :cry:
  • CATravelerCATraveler Solar Expert Posts: 98 ✭✭✭✭
    Re: Battery/load/controller connector

    I was also wondering what the OP meant by "2 battery banks". In general RV terminology a MH would have 2 battery banks. One for the chassis and one for the house. My Pace Arrow had 2 12V marine batteris for the house and one starting battery for the chassis as delivered from Fleetwood.

    I'm not sure what you have especially with prior changes. Mine had a diode isolator to charge both banks from the alternator. In that same area under the hood it also had an emergency start relay so there were lots of larger wires and lots of smaller wires. And there was also a DC fuse panel up there. It had some cheap charger that was built into the AC and DC distribution panel located under the refer. It didn't have good charging algorithms. It didn't have an inverter.

    It sounds like your rig has a pass through inverter and then I'm not clear if you have both an charger and converter.

    Perhaps some pics would help.
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    Sounds like your describing mine except mine is in the back under the bed. No inverter either. Some had manual switching but mine is all automatic.The charger was also optional.They got all the bells and whistles on this RV when they bought it back in 1883 oh I mean 1983 lol
    I have a wiring diagram/repair manual for the converter but I've never been good at figuring them out. All I want to do to it is disconnect the charger portion while leaving everything else intact.

    If you count the motor start battery then yes I do have 2 banks (with isolator/emer. start relay) so technically I'll be adding a 3rd.

    I was trying to charge those Trojan batteries with the inverter too late into the evening.When my charge controller rested it was at 12.3v(at the battery). I hooked up my portable 10a battery charger for 45 minutes and they were at 12.85!
    Nice to know I can get a good charge that quick.
  • westbranchwestbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Battery/load/controller connector
    hackman22 wrote: »
    I was trying to charge those Trojan batteries with the inverter too late into the evening.When my charge controller rested it was at 12.3v(at the battery). I hooked up my portable 10a battery charger for 45 minutes and they were at 12.85!.

    If that voltage was taken right after you disconnected the charger, they are not finished, the voltage should be ~ 13.2v.
    After resting 3 or more hours it could drop into the high 12.x volts
    hth
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    Got it.
    My cheap everstart batteries must be the problem. 12v Deep Cycle 110 aH I had 10 but returned 6. With 10 I thought I was low but I wasn't as low as I thought.
    I measured voltage with system well rested and from the batteries all the way to the cable going into the controller I'll get a reading of say 12.3 yet the controller will say 12.1!
    What is the point of having the battery voltage displayed if it is going to be wrong???

    Plus the charge controller (midnight classic 200) goes from bulk to absorb to float by midday yet when the sun goes down I'm at around 12.5 or less

    The four batteries don't seem to hold a charge very well considering they are new. The 6 I returned were tested and while I thought they were not even near fully charged when I took them in they all tested at 12.6 to 12.66 and the cranking amps (listed on battery at 750/Ah listed at 110) was 750 to 850. With 10 I could make it thru the night with a 23" tv /65W for 5 hours and a small AC box fan on low for 12 hours. With 4 I have to use an even smaller DC fan and I had to run the generator for an hour. (+ controller running,laptop on standby)
    I'm driving 90 miles shortly to get some Trojan batteries. I'll hook them up and repost on what I suspect will be a vast improvement.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    Batteries and Voltages and wires! Oh my! :D

    First, a difference of 0.2 Volts is pretty easy to get between any two spots on a 12 Volt system or any two meters or the same meter applied twice. Understanding the Voltage under what circumstances it is measured is important. For instance for SOC the only accurate Voltage will be at the battery with nothing connected after it has sat for a couple of hours at least. In an active system the Voltage will change moment by moment.

    Small wire sizes will cause Voltage drop, power loss, and inaccurate readings from point to point. This will be at its worst while under load. If you want to see how bad the V-drop is on any given wire you can take a Voltage reading from one end of it to the other. This will show the Voltage potential across the wire which is the V-drop.

    One of the nice things about some Morningstar controllers is their use of separate battery sense wires which 'look' at the battery Voltage independent of the charging leads and so tell the controller a more accurate number. Fancy controllers like Outback and (probably) MidNite allow yu to adjust the panel reading +/- according to an accurate reading taken with a really good meter at the battery terminals.

    As far as charging is concerned, just getting to Float doesn't really mean anything. You need to hit that 14+ Volts for Absorb and stay there long enough to "put the used Amp hours back". If the Absorb time is too short, you'll get Float but the battery is not fully charged. If it's too long you lose water and shorten the battery life.

    First clue you've got the wrong sort of batteries is when they list "cranking Amps". This means nothing to an RE system.
    Four of these things should be 400 Amp hours+, or up to 2.4 kW hours of power which is a lot. If they aren't performing like that it's because they don't really have the advertised capacity and/or your wiring/charging routine is shortchanging that capacity.

    It occurs to me that if you are going to have two parallel sets going to one of those bus bars you will not have a space for connecting some 1/0 to the inverter. You might better tie the battery strings together at the batteries and bring one 1/0 lead up to the bus bar from there and use the other large hole on it to feed the inverter. And don't forget the fuses! In this case I'd put one of the Blue Sea terminal fuses on each battery, and then have another for the inverter on its line from the bus bar to the inverter.

    Clear as mud, right?
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    Thanks,
    I didn't know I could adjust the controller reading.The wiring is all proper to it with an 80A breaker in-line.Voltage going in is not what's registering on the display.I'll see if it is adjustable tonight.
    I'm going to run 2 parallel battery banks with the switch so the 1 positive line from each will go to the switch.I'll only need one to the bar off the common.
    I pretty much figured out all the load wires present on the first battery.I checked them and all are fused. (I looked under the dash and there are also enough in-line fuses to decorate a christmas tree!....I quit looking.
    I'm headed to Corpus Christi in about 15 minutes to get some REAL batteries.That is the closest Trojan dealer.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    One issue with running two batteries on an 'A'/'B' switch: where does the charge controller connect? You can't have it on both at once otherwise you create a path for load draws through the charger wiring (not good). If you connect it to the bus bar then only the battery connected to the bar at that time will receive charge. This becomes a problem if you forget to switch between the two regularly; the unused battery will self-discharge, sulphate, and die prematurely.

    Blue Sea (or anyone else) has yet to make a common mode DPDT battery switch to handle this. :p
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Battery/load/controller connector
    One issue with running two batteries on an 'A'/'B' switch: where does the charge controller connect? You can't have it on both at once otherwise you create a path for load draws through the charger wiring (not good). If you connect it to the bus bar then only the battery connected to the bar at that time will receive charge. This becomes a problem if you forget to switch between the two regularly; the unused battery will self-discharge, sulphate, and die prematurely.

    Blue Sea (or anyone else) has yet to make a common mode DPDT battery switch to handle this. :p

    This is where diodes traditionally come in. They allow the CC to feed to both battery banks but no power to flow from one bank to the other.
    When this is done the diodes need to connect directly to each of the banks, bypassing switches, bus bars, etc.
    If you do this and your CC does not have remote sensing leads (with diodes????), then you will have to increase each of the voltage settings in the CC by the amount of the diode voltage drop. The increase in Float will be just the drop in the diode under low current. The increase in Absorb will need to be the voltage drop in the diode when carrying full output current.

    The folks at smartgauge.co.uk do this with relays instead, to avoid the voltage drop.
    SMA SB 3000, old BP panels.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Battery/load/controller connector

    inetdog,
    this won't work with most controllers as the controllers need to see the battery voltage and they actually operate from the battery. those diodes which protect each battery from seeing each other also prevent the controller from seeing either of the batteries.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Battery/load/controller connector
    niel wrote: »
    inetdog,
    this won't work with most controllers as the controllers need to see the battery voltage and they actually operate from the battery. those diodes which protect each battery from seeing each other also prevent the controller from seeing either of the batteries.

    Thanks NIEL. Rethinking:

    Well, actually it would be seeing whichever of the two batteries is currently (NPI) at the lowest voltage, plus the diode drop. Unless the controllers actually interrupt their output current momentarily to make the battery voltage measurement. Do the sophisticated CCs do that?

    And since most CCs do, I have heard, take initialization power for their control electronics from the batteries, and therefore need to be connected to the batteries first, you might be able to get away with a resistor in parallel with each diode. Low enough resistance to supply a small amount of power to the CC when needed, but high enough to keep the battery-to-battery current small when the CC is off.

    The fact that the input power (from panels) comes and goes each day certainly does provide a more complex environment for the CC than a simple alternator or generator has to work with.

    And for a combined inverter-charger, nothing will work except manual switching and remembering to change periodically or else relay-controlled switching or an alarm when one bank stays low for too long.
    SMA SB 3000, old BP panels.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Battery/load/controller connector

    "Well, actually it would be seeing whichever of the two batteries is currently (NPI) at the lowest voltage, plus the diode drop."

    won't work. the diodes present a one way for the voltage toward the battery. the battery power would need to be present to run the controller so no power to the cc to send the pv power on to the batteries.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Battery/load/controller connector
    niel wrote: »
    "Well, actually it would be seeing whichever of the two batteries is currently (NPI) at the lowest voltage, plus the diode drop."

    won't work. the diodes present a one way for the voltage toward the battery. the battery power would need to be present to run the controller so no power to the cc to send the pv power on to the batteries.

    Which is why I also added the next paragraph:
    And since most CCs do, I have heard, take initialization power for their control electronics from the batteries, and therefore need to be connected to the batteries first, you might be able to get away with a resistor in parallel with each diode. Low enough resistance to supply a small amount of power to the CC when needed, but high enough to keep the battery-to-battery current small when the CC is off.
    SMA SB 3000, old BP panels.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    Not only initial power, but running power. Below a certain Voltage they won't start up or operate. They don't ever really shut off either (except the El Cheapos).
    Nope; the diodes won't do it.

    And yes, I did run parallel but separate banks at one time. Went 'round and 'round trying to overcome this exact problem. Decided it wasn't worth the effort.
    You can use a back-up bank with a manual switch and a charge control relay on the AUX of your MX60; reaches Float, switches to secondary bank to make sure it's charged. Switch allows using second bank to feed inverter if necessary.

    On the whole it is easier and more dependable to have one battery bank, even if it's two batteries in parallel.
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    Wow Quite a debate!
    I was just going to use the second battery bank for more of an emergency bank like a week of awful weather for example.My idea was to have the controller hooked up with all the other loads that way which ever bank I switched on, the connections would be made.
    I'm scratching that plan for now. I drove down to Corpus yesterday and got four new t105's. When I got home I tested the specific gravity in the everstart batteries which had been charging all day. I tested numerous cells and got about 1200 on all of them. I check a Trojan just to verify the tester and it was excellent. I'm taking the last four back to walmart tomorrow.
    I spent almost 1000 on the 10 crap batteries.The Trojans were only 615 including cables.
    At least I figured it out in time to not lose all that money.
    I'm still not real happy with the charge controller. It registered 12.2V last night but it was actually 12.8V. I can't adjust it if the difference changes.
    I took the 12.8V reading at the connection of the controller so it can't be loss.
    I guess I could just get a little DC digital display and mount it right below the controller but you'd think the controller could give that info. I mean what is the point of displaying 12.2v.Might as well not display it at all.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector

    It was actually 12.8 according to what?
    That's a problem, you see; the accuracy of one Voltmeter is only in comparison to another. Before you adjust the MidNite's V+/- be sure you have a really good reading to compare it to.
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    I have an accurate Fluke multimeter.The batteries were new so I knew 12.2 was wrong which is why I checked. I can't adjust it because sometimes it's off by .2V other times up to .6V
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    I JUST CHECKED IT IN FLOAT with the Fluke and a new amp meter (+volts) I got yesterday
    13.8v on the new one 13.8 on the Fluke 13.4V on the controller.I was thinking maybe the temperature compensator?
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Battery/load/controller connector
    hackman22 wrote: »
    I have an accurate Fluke multimeter.The batteries were new so I knew 12.2 was wrong which is why I checked. I can't adjust it because sometimes it's off by .2V other times up to .6V

    The only time you can adjust the Voltage difference is when current flow is zero and the batteries are fully charged. Anything else tends to be inaccurate by nature.
    Also if the MidNite has the RTS on it it will be more accurate than the Fluke.
  • BB.BB. Super Moderators, Administrators Posts: 32,005 admin
    Re: Battery/load/controller connector

    Some controllers display the temperature corrected voltage.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hackman22hackman22 Solar Expert Posts: 27
    Re: Battery/load/controller connector

    The midnight is definitely inaccurate. I understand I'm not getting a correct reading but the Fluke is way closer then the controller is to the correct.This with minimal load and full charge.
    You would think that taking a measurement on the battery + cable,where it goes in to the controller, would be the same as on the display. I could see a .1 difference but .6?
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