Announcement

Collapse
No announcement yet.

Help with EPSolar 3415N controller

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Help with EPSolar 3415N controller

    I have 2 identical systems each system consists of: 5 panels watt = 1075 (@24V) BlueSun Solar Mono panels wired in parallel; fused to 1 x (EP Solar) ET3415N controller; 1 x disconnect switch; 4 x 430 L-16 US Battery 6 volt wired in series for 24 volts. Batteries in parallel, 2 sets.

    I live in a northern climate (central Ontario, Canada) off the grid where the months of Oct-Nov especially are brutal for solar. We do not run an extensive array of electrical appliances, heat with wood, cook with gas, but everything else is run off a 2kw inverter, and our power consumption does not amount to a lot.

    I maintain my batteries during this time through use of a home-made charger (old snowmobile engine with a 24 volt 45 amp alternator and cooling fan.

    Here is my problem. I do run the charger daily when there is no sun and that helps, but it does not produce enough power to really boost up the batteries and is a bit noisy.

    I believe part of the solution may be with the controllers. On a good solar day they will put out 30 amps each per hour, but the controller reads voltage in the batteries and once the voltage reaches a given limit the controller scales back on the charge assuming that the batteries are at full charge. My hydrometer may read between 1175-1225 at that time.

    So, are there any changes that I can make in the parameters in the controller to make it continue charging at a higher rate, like increasing the charge rate. Or, does anyone have any suggestions or recommendations. All suggestions are welcome.

  • #2
    The controller isn't scaling back the charge current, it is just holding voltage. At the voltage that is set, what you are seeing is that the battery just can't accept more current. This is called the absorb stage of charging.

    You can't fully recharge the battery without getting through the absorb stage, and that takes time, because you need to soak the battery at voltage and allow the current to taper down. It just isn't possible to do properly with short solar days.

    If you can increase the voltage setting a bit, you might be able to get more charge into it in a shorter time.
    CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

    Comment


    • #3
      The EP3415N is fully programmable so you can change the charge and float voltages and other parameters.

      A couple of questions
      1. Do you have a manual for the controller?
      2. Have you wired up the remote temperature and battery voltage sensor cables?
      3. What battery type do you have the EP3415N programmed for?

      Simon

      Off grid 24V system, 6x190W Solar Panels, 32x90ah Winston LiFeYPO4 batteries installed April 2013
      BMS - Homemade Battery logger github.com/simat/BatteryMonitor/wiki
      Latronics 4kW Inverter, homemade MPPT controller
      Off-Grid LFP(LiFePO4) system since April 2013

      Comment


      • #4
        What are the specs of your panels? 215 watt panels could be 60 cell, (Too low voltage) or 72 cell (24 volt nominal). Either way you are not putting high enough voltage with parallel wiring into your MPPT controller for a 24 volt battery bank. Also with 5 panels you cant series wire all 5 together, too high of voltage, so you can only use 4 of them, probably in a 2S2p configuration.
        2.2kw Suntech mono, Classic 200, NEW Trace SW4024

        Comment


        • #5
          Originally posted by littleharbor View Post
          What are the specs of your panels? 215 watt panels could be 60 cell, (Too low voltage) or 72 cell (24 volt nominal). Either way you are not putting high enough voltage with parallel wiring into your MPPT controller for a 24 volt battery bank. Also with 5 panels you cant series wire all 5 together, too high of voltage, so you can only use 4 of them, probably in a 2S2p configuration.
          72 cell panels, wired in parallel, are fine for a 24 V system using an mppt controller.
          CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

          Comment


          • #6
            We don't know yet what they are 60 or 72. But parallel wiring 24 volt panels into an MPPT controller to charge a 24 volt battery defeats the whole purpose of having a 150 Voc, high dollar controller IMHO. In a hot climate the Vmp would just be enough to charge the battery and you really aren't going to gain any benefit for your hard earned dollars.
            2.2kw Suntech mono, Classic 200, NEW Trace SW4024

            Comment


            • #7
              it's a trade off, battery life, charge rate, charge voltage.

              Here's a crass rule of thumb. The time it takes to bring the battery bank up in voltage from Sunrise to the end of BULK. can be thought of as the same amount of time needed to dwell in the Absorb part of the cycle. In winter, with 3 solar hour days. you have 90 min to bulk, and then another 90 min for Absorb. If your array can, on average, hit bulk in 1 hour, you may only need 1 hour of Absorb. Or, if you need 3 hr for bulk, the sun goes down before you can complete 3 hours of absorb. In that case, you could try raising the bulk/absorb voltage a bit to charge faster/harder to try to prevent battery sulfation. Or you may need more PV.
              Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
              || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
              || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

              solar: http://tinyurl.com/LMR-Solar
              gen: http://tinyurl.com/LMR-Lister

              Comment


              • #8
                Thanks to all the members who posted responses. First, I do have the manuals and will change the parameters for the bulk charge. I will also run my charger even on a good day if your responses are positive for doing this. As for the battery temperature sensors they both craped out and I purchased new ones but they do not appear to be giving an acurate reading.

                Comment


                • #9
                  Originally posted by littleharbor View Post
                  We don't know yet what they are 60 or 72. But parallel wiring 24 volt panels into an MPPT controller to charge a 24 volt battery defeats the whole purpose of having a 150 Voc, high dollar controller IMHO. In a hot climate the Vmp would just be enough to charge the battery and you really aren't going to gain any benefit for your hard earned dollars.
                  OP is in central Ontario, Canada. The difference between pwm and mppt output for panels only in parallel will be substantial, especially in winter, when maximizing every daylight hour matters most.
                  CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                  Comment


                  • #10
                    Originally posted by Dougahole View Post
                    As for the battery temperature sensors they both craped out and I purchased new ones but they do not appear to be giving an acurate reading.
                    This could be a problem unless the battery is being held at a constant temperature. The correct charge voltage is dependant on temperature, the colder the battery temperature the higher the charge voltage.

                    I am fairly sure that the temperature sensors are just a thermistor (a resistor that changes its resistance with temperature). If this is the case you can check them with a multimeter on the resistance range. With the sensor unplugged measure the resistance between the two terminals on the plug. The resistance should remain constant with constant temperature and drop if you heat the probe up by warming it up in your hand.

                    Can you give more details of what you mean when you say they don't appear to give an accurate reading.

                    Simon

                    Off grid 24V system, 6x190W Solar Panels, 32x90ah Winston LiFeYPO4 batteries installed April 2013
                    BMS - Homemade Battery logger github.com/simat/BatteryMonitor/wiki
                    Latronics 4kW Inverter, homemade MPPT controller
                    Off-Grid LFP(LiFePO4) system since April 2013

                    Comment

                    Working...
                    X