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  • #16
    It looked like the history can be turned on through the powerhead only in menu I but I'm still a bit uncertain. Anyway I monitor this while charging where to have a history which is a data logger would be valuable.

    Jim

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    • #17
      Testing: Day 1

      As is my habit, I document as I go so the reader can follow along and (hopefully) I'll get feedback from the forum members.

      First, all of the batteries and a lot of wiring is contained in the "box" shown in the photo below.

      Click image for larger version  Name:	Box Here.JPG Views:	0 Size:	130.4 KB ID:	28376
      The pic below is the initial install (so there's some differences now) but the batteries are in the same place and it gives you a good idea of whats-where.

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      UGH! I just realized something. Look closely at the picture above--I've got the battery temp monitor connected to switch 2's ON/OFF post! The temp probe is probably not recording the battery temperature accurately. <sigh> Gotta move that before doing any more testing. For the sake of documentation I'll continue with the methodology so the next time all I'll have to do is post the results.

      I've got the temperature alarm in the BMV-712 set to notify me at 120 degrees F and then turn off at 115. Totally arbitrary on my part, except I know 120 is well below when the Battle Borns (BB) will shut off if their internal temp reaches 135 (as determined by the battery management system, or BMS). The BMS' temp reading is not accessible.

      Click image for larger version  Name:	configuration.JPG Views:	0 Size:	45.5 KB ID:	28378

      IF I end up installing fans I'll pull from the street side (where the Nautilus is located) and exhaust (push) out the curb side where the inverter is located. To test what happens in the area where I am contemplating installing the intake fan, I taped up the Elitech and started recording.

      Click image for larger version  Name:	Elitech.JPG Views:	0 Size:	82.6 KB ID:	28379

      I was not surprised that the temperature did not fluctuate at all during the first test. It stayed consistent at ~90 degrees (the same temperature as the interior of the camper).

      Click image for larger version  Name:	11 Elitech Results.JPG Views:	0 Size:	82.6 KB ID:	28380

      More on the first test in the next post....


      Last edited by howson; 08-31-2020, 03:09 PM.
      Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

      2017 Ford F-350 DRW, '19 315RLTSPlus

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      • #18
        Test Day 1 (cont)

        The interior of the camper, as mentioned in the last post, was 90 degrees. The batteries were charged to 100% and the battery temp was 95.

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        I turned on the bedroom air conditioner and within minutes the temperature started rising immediately. (Remember the sensor is installed wrong at this point so these results could be totally wrong.)


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        A minute later I got the first alarm (>=120 degrees!) so I turned off the air conditioner.

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        Minutes later the temp lowered enough for the alarm to cancel.

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        Below is how it was recorded on the VRM Portal dashboard:

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        So that's the method I'll use to test different configurations. For now I need to get out there and move that temperature sensor. It needs to be on the + terminal of a battery, not the on/off switch.

        Constructive criticism and/or suggestions are encouraged and appreciated.

        Howard
        Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

        2017 Ford F-350 DRW, '19 315RLTSPlus

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        • #19
          I love reading your posts Howard. I geek out on technology and like to log data that I really don't need but feel compelled to document anyway. Without lifting a finger, I can do all kinds of upgrades to my RV virtually by following your posts. You are one of the best I've seen at researching and documenting your work. Really outstanding. Your posts usually do cost me money though. I ordered the Victron temp sensor yesterday. My batteries are in the front compartment and I'm curious how hot they get on 110 degree days. Plus, I need to log some data!

          BTW, I'll be curious to see the difference in temps once you move the sensor to the battery terminal.
          Brian & Kellie
          2020 Grand Design Solitude 310GK-R, FBP, MORryde IS, 1,460w solar and 540ah BBGC3
          2020 Ford F-350 Platinum SRW PSD Tremor, 60g TF fuel tank, Hensley BD3-F air bag hitch

          Previous setups:
          2019 Grand Design Solitude 373FB-R, 2019 Ford F-350 Platinum DRW Powerstroke, Hensley BD5 air bag hitch
          2016 Grand Design Reflection 318RST, 2016 GMC 3500 Denali SRW Duramax, Hensley BD3 air bag hitch

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          • #20
            bertschb -- thanks for the kind words.

            ---break---

            So the temperature sensor is moved from the on/off switch to a positive battery post. The post chosen was the most convenient to access (which was not convenient). The X shows where the sensor was, the arrows show the same thing but the picture on the left is a close up view.

            When I initially installed the sensor (where the "X" is) my thought process was that the sensor needed +12v...which was the wrong interpretation of the instructions. The lug at the end of the wire is actually the sensor and it must be connected to a battery post (the positive one), not just to a +12v source.

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            I ran a second test after putting everything back together.

            First--the Elitech's results (measuring the temp in the Nautilus cavity) were consistent 89 degrees, so I'm not posting that chart.

            To save you from over a dozen screenshots of the BMV, here's a chart of the results (since you know the testing methodology from the previous post):

            Click image for larger version

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            The graph (you can see the first test, followed by the gap when I had the system off while moving the sensor, then the second test):

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            Bottom line: moving the sensor made a huge difference. (Duh, huh?) I'm still not thrilled with the rise in temp, though, so will probably still consider some type of supplementary air flow. Based on the room I have to install fans, the 120mm size is too big. I'm considering using a smaller 80mm (I wouldn't use the wall wart) with the three speed controller:

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            First I'm going to try putting vents in the panel. I'd rather not add anything that draws power from the battery.

            As always, constructive inputs will be very welcome.

            -Howard
            Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

            2017 Ford F-350 DRW, '19 315RLTSPlus

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            • #21
              Howard,

              The results at the battery are much more favorable but I'm curious if you are experiencing high resistance at your switch to have such high temperatures there. Your switch contact should be running cooler than the battery terminal under high load. It would also be interesting to gather temps from the positive posts from the inside batteries.

              Jim
              Last edited by Guest; 08-31-2020, 08:18 PM.

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              • #22
                Originally posted by MidwestCamper View Post
                Howard,

                The results at the battery are much more favorable but I'm curious if you are experiencing high resistance at your switch to have such high temperatures there. Your switch contact should be running cooler than the battery terminal under high load. It would also be interesting to gather temps from the positive posts from the inside batteries.

                Jim
                Any individual battery is supplying 1/4 of the load, so the temp should be lower. Where I had the sensor, 100% of the current was flowing through the on/off switch connection. The switch is rated for 500A surge (300A constant), so I doubt the temp seen is an issue. There's no indication of any form on any of the lugs, connections, wires of a problem--nothing. It all looks very good. No corrosion, melting--nothing. I'm very pleased with the install and what I saw when moving the sensor.

                Click image for larger version  Name:	300A switch.JPG Views:	0 Size:	36.6 KB ID:	28423

                Howard
                Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

                2017 Ford F-350 DRW, '19 315RLTSPlus

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                • #23
                  Originally posted by howson View Post

                  Any individual battery is supplying 1/4 of the load, so the temp should be lower. Where I had the sensor, 100% of the current was flowing through the on/off switch connection. The switch is rated for 500A surge (300A constant), so I doubt the temp seen is an issue. There's no indication of any form on any of the lugs, connections, wires of a problem--nothing. It all looks very good. No corrosion, melting--nothing. I'm very pleased with the install and what I saw when moving the sensor.

                  Click image for larger version Name:	300A switch.JPG Views:	0 Size:	36.6 KB ID:	28423

                  Howard
                  Howard,

                  I still think its odd that the switch is heating up like this. This would indicate resistance and not from being heated by the actual battery cells. Our batteries will heat due to the heat release from the cumulative heat from the batteries cells. Also the peak rating of the switch is 300 amp continuous. What is the peak draw on your system?

                  Jim

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                  • #24
                    Originally posted by MidwestCamper View Post

                    Howard,

                    I still think its odd that the switch is heating up like this. This would indicate resistance and not from being heated by the actual battery cells. Our batteries will heat due to the heat release from the cumulative heat from the batteries cells. Also the peak rating of the switch is 300 amp continuous. What is the peak draw on your system?

                    Jim
                    Jim--thanks for the thought-provoking post.

                    First--are we discussing continuous or peak? Peak is 500A for the switch. Continuous is 300A.

                    Four Battle Borns can push out a bunch of amps in a short burst. A lot. Like 300A each if I remember correctly, so 1200A out of my 4 batteries? Yikes--hope that never happens. (Something short circuited if it does.) Max continuous is 400A (100A each), but I didn't plan nor want that capability. The batteries would only last an hour at that rate. That's why I was OK with the 300A continuous rating of the Blue Sea switches. The Multiplus is rated for 25A of 120vAC, so max continuous should never exceed 250A of 12vDC for a significant period of time.

                    As shown in the chart in post 20, the most current being drawn from the batteries to the inverter with the bedroom a/c running is 150A. That's 37.5A from each battery assuming an equal load from the parallel bank. A BB can easily handle that load.

                    So the question is, "What's the normal temperature for a connection at the on/off switch with 4/0 gauge wiring and a copper lug with 150A going through it with an ambient temperature of 90 degrees?" (I have no idea.) Without any other evidence of a problem or a standard to compare it against, I don't consider it an issue at this time. Could it be an issue? Maybe. But without evidence I think it's OK (but certainly open to evidence that proves otherwise).

                    gbkims will probably find a chart somewhere.
                    Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

                    2017 Ford F-350 DRW, '19 315RLTSPlus

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                    • #25
                      howson Howard,

                      I believe a word back from Gene or the other electrical guys would be helpful in discussing why the switch is getting hot. Maybe this much heating is normal considering the amount of current that is being passed though the connection? Is the cable also getting hot? Heat at the switch is a sign of resistance at the connection. Heat generated from the battery is also resistance but it's internal to each cell in the battery where the two are not connected outside of measuring stabilized passthrough temperature under no load..

                      Good news the batteries are running much cooler. And your work in performing these tests is very nice.

                      Jim

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                      • #26
                        I went to Ace Hardware a bought a few vents. One is on the back panel for hot air to escape and I cut one hole on the street side for air to enter. (The assumption is the air near the Nautilus panel is cooler than the air in the box, so air *should* flow from cool to hot, right?) The tape is just a temporary way to hold the vent on during testing.

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                        Today was very hot--bright sunshine and it was near midday. The conditions simulated what would be encountered on a travel day. The bedroom did not cool nearly fast enough (really not surprising) and I was not surprised by the rise in temperature from the battery.

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                        While the temps are well below the maximum operating temp of the BB batteries, I'm going to get one fan to force air into the box and test again in the future.

                        Howard

                        P.S. I'm going to paint the vents black and screw them to the panel to make the install look good--hopefully by the next time I post on this topic.
                        Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

                        2017 Ford F-350 DRW, '19 315RLTSPlus

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                        • #27
                          I grouped together some of the info I found while reading about current/temperatures.
                          As usual learned some things I didn't know or took for granted.

                          Battery Ventilation
                          "Batteries also require ventilation to dissipate heat generated during normal heavy charging.
                          ...ensure that a gap of no less than ¼" (6mm) exists between any two batteries to allow heat to dissipate."
                          http://stevedmarineconsulting.com/wp...nk133_03-1.pdf

                          Wire Current vs Temperature Rise
                          4/0 is off this chart: https://www.is-rayfast.com/news/wire...se-by-current/

                          Switch

                          Blue Sea 6006
                          For battery switches the continuous current rating is established by testing for one hour at the rating.
                          This is reasonable since thermal equilibrium would be reached within one hour.

                          Carlingtech BD-Series - https://www.carlingtech.com/sites/de...ne_Catalog.pdf
                          Temperature Rise Terminal should not exceed 60°C above ambient

                          Littelfuse - Battery Disconnect Switch Brochure https://cta-redirect.hubspot.com/cta...f-3aa3bbb9525b
                          Continuous Rating - The rating meant to indicate what the device can handle forever with no interruption.
                          It is usually measured as the amperage that a device can handle for one hour without exceeding the maximum allowed temperature rise at the terminals.

                          BEP 701
                          BEP Marine Battery Switch Test Procedures (UL 1107) Continuous (1 hour), intermittent (5 minutes) and Cranking (engine starting - 10 seconds).
                          The test is to determine the maximum current the switch can handle for the stated time, without the rear terminals exceeding 100 deg C (212 deg F) above the ambient temperature. The continuous and intermittent ratings are tested at 110 percent of specified ratings. All BEP switches are tested Independently to this specification by a 3rd party laboratory.
                          https://www.bepmarine.com/en/701


                          Ambient Temperatures:
                          30°C = 86°F = Ambient for NEC Table 310.16
                          40°C = 104°F
                          50°C = 122°F = Ambient for Marine Engine Space

                          90°C = 194°F
                          105°C = 221°F

                          Engine Space Ambient
                          * De-rating for engine space is 0.85 for 221°F / 105°C rated wire

                          UL1426 Marine wire should generally be 105°C rated

                          ABYC Ampacity Rating Table at 30°C = http://assets.bluesea.com/files/reso...ence/21731.pdf

                          Wire Size ABYC Ampacity Rating Table at 30°C (86°F) Temperature Rating of Conductor Insulation
                          6 Awg 120 Amps (Not in Engine Room) -------------------105°C
                          2/0 330 Amps (Not in Engine Room) -----------------------105°C
                          4/0 445 Amps (Not in Engine Room) ------------------------105°C
                          Data based on E-11 Table VI-A (Single Conductors in Free Air)

                          6 Awg 84 Amps (Not in Engine Room) ----------------------105°C
                          2/0 231 Amps (Not in Engine Room) -------------------------105°C
                          4/0 312 Amps (Not in Engine Room) -------------------------105°C
                          Data based on E-11 Table VI-B (Up to three conductors in a sheath, conduit or bundle)


                          Switch: Possible source of switch contact arcs.
                          Depends on how an Inverter/Charger is powered up.
                          If AC Power is 1st applied, then the Inverter's DC Bus Capacitors are charged up by the Inverter/Charger
                          If DC Power is 1st applied, then Inrush current from the Batteries into the Inverter's discharged DC Bus Capacitors.
                          The DC Bus Capacitors discharge in a few hours when Inverter/Charger is powered off and isolated from the batteries..

                          Pre-Charge
                          Inverter/Chargers with large Capacitor Banks (DC bus capacitors): Switch Contacts & Battery BMS
                          Pre-Charge for initial current spike that is created when connecting directly to the large capacitors (> 5 milliFarads) that are typically on the DC input side of the inverter/chargers

                          Battle Born BB10012 Manual and Installation Guide.
                          Inverter/Chargers (and other devices having large input capacitance > 10 microF)
                          Special consideration must be made for connection to devices that have a large input capacitance, because of the tendency of these devices to draw large current spikes upon initial connection to the batteries.
                          Last edited by gbkims; 09-07-2020, 12:02 PM. Reason: Fixed Typo. 40°C = 104°F
                          Gene and Kim
                          2015 Grand Design Reflection 317RST
                          2017 RAM 3500 CC, LB, 4x2, 6.7L CTD

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                          • #28
                            gbkims ......that's a lot to absorb!

                            What I get from the info as I worked my way through the links is it's normal for a wire (or connection) to experience some temperature rise under a heavy load.

                            In another lifetime there was a "multimeter" (it was huge) that would inject a very high voltage across a connection to measure the resistance to ensure it was low enough that a large EMP wouldn't have a negative effect. I write that to give perspective as to why I am not surprised that a wire, or copper lug, will experience some heating under a large load. Those components are, in effect, resistors (very small ones but that's the effect on the overall 12v inverter circuit).

                            Of special note is the Battle Born notes at the end. A forum member has experienced this issue with a Multiplus 3000/12 connected to BBs. Lengthening the wire from the battery bank to the Multiplus (effectively adding resistance and a micro-second more of a delay) eliminated the problem.

                            Howard

                            Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.

                            2017 Ford F-350 DRW, '19 315RLTSPlus

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                            • #29
                              Howard,
                              Yep, short version is the wires and equipment warm up with the current.
                              A low ohms meter like Megger DLRO10 was used by our electrical tech to check contact resistance on 4160V switchgear starters.
                              Gene and Kim
                              2015 Grand Design Reflection 317RST
                              2017 RAM 3500 CC, LB, 4x2, 6.7L CTD

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                              • #30
                                Originally posted by gbkims View Post
                                Howard,
                                Yep, short version is the wires and equipment warm up with the current.
                                A low ohms meter like Megger DLRO10 was used by our electrical tech to check contact resistance on 4160V switchgear starters.
                                Gene,

                                Excellent information. Without specialized equipment, It would be tempting to hold the highest possible load for one hour to check temperatures of components. For my single battery system, this will be during charging where a one hour charge is typical for my system at 56 amps or so.

                                What is the recommendation for making high current, low resistance connections? Crimp or crimp with solder? Use of a contact grease like below?

                                https://www.sanchem.com/electrical-c...lubricant.html

                                Jim
                                Last edited by Guest; 09-06-2020, 09:14 AM.

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