<div dir="ltr"><div>Hey Wrenches... <br><br>It's not a good idea to run this based on temperature...    You want the fan to come on when the batteries are gassing. If the battery temperature is cold and they are charging, it could still be gassing.  This would result in the fan not running and potentially lead to hydrogen ignition.  Typically, you turn the fan on at or just above float voltage, and it runs until the voltage falls .2 to .4 volts below the float voltage. <br><br>You want the fan to be sealed and brushless so that there is no chance that it'll ignite the hydrogen being expelled from the box. If the fan is sealed like the zephyr fans, it won't corrode. <br><br>If you are tying a Sol Ark inverter to a lead-acid bank, it's a good idea to contact Sol Ark and have them push the firmware that allows you to adjust the tail current time.     With their tail current set to only 10 mins and no way to program absorb timers, this will result in chronically undercharged FLA/AGM or GEL batteries. <br><br>You should use the EQ V, EQ Time, and EQ Frequency to simulate a normal bulk/absorb timer...   Depending solely on the tail current for the time of every charge cycle will result in undercharging issues.  Typically, the EQ frequency is set from 2-7 days for full-time systems or 14 to 30 days for backup or lightly loaded systems. <br><br>Another thing to keep in mind is that they utilize the battery's internal resistance to increase charging voltage and current, which is supposed to help break up sulfation. From my experience, this cooks the battery. The issue with this is that it's not temperature-compensated.    I would defeat this by setting the internal resistance to 0 or 1 mΩ.    What happens here is that if the measured internal resistance is higher than programmed, it'll bump up the voltage and current to lower that resistance.  If the battery is already sulfated, it'll become so hot that it'll gas very quickly. Alternatively, if it's an AGM or GEL battery, it'll cook the battery electrolyte, causing the bank to dry out, swell, and fail.   In the past, I have seen them charge at over 66 volts. Since disabling this, I have not seen the Sol Arks do this. </div><div><br></div><div><br><br><br></div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div style="float:left;padding:1px 10px 0 0"><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"></a><a href="http://www.rollsbattery.com" target="_blank"><img src="https://i.imgur.com/YIluKhq.png" alt="" style="padding:3px 0px 0px 10px;float:left;margin-right:10px;width:98px;height:115px"></a><div style="font-style:normal;font-variant:normal;font-weight:bold;font-stretch:normal;font-size:14px;line-height:20px;font-family:Arial,Helvetica,sans-serif;margin:0px"><font color="#bb1a1d">Steve Higgins ⋅ 
</font><span style="color:rgb(64,64,64);font-size:12px">Technical Services Manager</span> 
</div> 
<div style="font-style:normal;font-variant:normal;font-weight:bold;font-stretch:normal;font-size:12px;line-height:20px;font-family:Arial,Helvetica,sans-serif;margin:0px"><font color="#bb1a1d"> 
t</font><span style="color:rgb(184,39,106)"> 
<span style="font-weight:normal;color:#404040">+1.902.597.4020</span>  </span><font color="#bb1a1d">m</font> 
<span style="color:rgb(64,64,64);font-weight:normal">+1.206.790.5840</span></div><div style="font-style:normal;font-variant:normal;font-stretch:normal;font-size:12px;line-height:20px;font-family:Arial,Helvetica,sans-serif;margin:0px"><font style="font-weight:bold" color="#bb1a1d">f</font><font color="#cf1d0c" style="font-weight:bold"> </font>+1.902.597.8447  <font style="font-size:12px;font-weight:bold" color="#bb1a1d">e</font><span style="font-size:12px"> 
</span><span style="font-size:12px"><a href="mailto:steve@surrette.com" style="color:rgb(64,64,64);text-decoration:none" target="_blank">steve@surrette.com</a></span></div> 
<div style="padding-top:8px"><a href="http://www.facebook.com/RollsBattery" target="_blank"><img src="http://cdn3.iconfinder.com/data/icons/free-social-icons/67/facebook_square_gray-24.png" alt="" style="border:none"></a><a href="https://www.youtube.com/user/RollsBattery" target="_blank"></a><a href="https://www.youtube.com/RollsBatteryEngineering" target="_blank"></a><a href="https://www.youtube.com/RollsBatteryEngineering" target="_blank"></a><a href="https://www.youtube.com/RollsBatteryEngineering" target="_blank"><img src="http://cdn3.iconfinder.com/data/icons/free-social-icons/67/youtube_square_gray-24.png" alt="" style="border:none;margin-left:5px"></a><a href="https://www.linkedin.com/company/rolls-battery-engineering" target="_blank"></a><a href="https://www.linkedin.com/company/rolls-battery-engineering" target="_blank"></a><a href="https://www.linkedin.com/company/rolls-battery-engineering" target="_blank"><img src="http://cdn3.iconfinder.com/data/icons/free-social-icons/67/linkedin_square_gray-24.png" alt="" style="border:none;margin-left:5px"></a><a href="http://www.instagram.com/RollsBattery" target="_blank"></a><a href="http://www.instagram.com/RollsBattery" target="_blank"><img src="https://cdn3.iconfinder.com/data/icons/free-social-icons/67/instagram_square-24.png" style="margin-left:5px"></a></div><div style="padding-top:8px"><div style="padding-top:0px"><div style="padding-top:0px;max-width:450px"><span style="color:rgb(153,153,153);font-family:Arial,Helvetica,sans-serif;font-size:10px;line-height:10px"><div style="font-size:10px;color:rgb(153,153,153);padding-top:0px"><span style="font-family:Arial,Helvetica,sans-serif;line-height:10px"><span style="font-family:Arial,Helvetica,sans-serif;line-height:10px"><hr style="font-size:10px;color:rgb(153,153,153)"><div style="font-size:10px;color:rgb(153,153,153);padding-top:0px"><span style="font-family:Arial,Helvetica,sans-serif;line-height:10px">CONFIDENTIALITY: </span><span style="color:rgb(153,153,153);font-family:Arial,Helvetica,sans-serif;font-size:10px;line-height:14px">The information transmitted herein is intended only for the addressee and may contain confidential, proprietary and/or privileged material. Any unauthorized review, distribution or other use of or the taking of any action in reliance upon this information is prohibited. If you receive this email in error, please contact the sender and delete or destroy this message and all copies.</span></div><hr></span></span></div><table></table></span></div></div></div></div></div></div><br></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Tue, Jun 3, 2025 at 6:47 PM Jay via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="auto"><div dir="ltr"></div><div dir="ltr">It’s a good idea to go with ac fan.</div><div dir="ltr">Simple and easy </div><div dir="ltr">And there isn’t any charging if the inverter goes down. </div><div dir="ltr">Jay</div><div dir="ltr"><br></div><div dir="ltr"><br><blockquote type="cite">On Jun 3, 2025, at 3:52 PM, Jerry Shafer via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" target="_blank">re-wrenches@lists.re-wrenches.org</a>> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><div dir="auto"><p dir="ltr">Wrenches, Dave, <br>
</p><p dir="ltr">I have had success with CPU fans, 12,24,48 vdc, 120 vac use no power and run them through a thermostat set at 80 to 90 degrees </p><p dir="ltr">Fun times</p></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jun 3, 2025, 1:30 PM Roy Butler via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" target="_blank">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>

  
    
  
  <div>
    <font size="2">Dave,<br>
      <br>
      The Morningstar Relay Driver can work as a stand alone unit, it
      can derive it's power from the battery bank.<br>
      This allows it to be programmed for voltage based relay operation
      which is ideal for vent fan applications.<br>
      <br>
      The relay channels are dry contacts and have a current limit of
      750mA. This will run a fan somewhat larger<br>
      than the good old Zephyr vents.<br>
    </font><br>
    <pre cols="72">Roy Butler
Four Winds Renewable Energy, LLC
<a href="https://www.google.com/maps/search/8902+Route+46?entry=gmail&source=g" target="_blank">8902 Route 46</a>, Arkport, NY 14807
607-324-9747  

Education is when you read the fine print; experience is what you get when you don’t.

“The less people know, the more stubbornly they know it.”

Although no trees were killed in the sending of this message, 
a large number of electrons were terribly inconvenienced.

                
</pre>
    <div>On 6/3/2025 2:22 PM, Dave Tedeyan via
      RE-wrenches wrote:<br>
    </div>
    <blockquote type="cite">
      
      <div dir="ltr">
        <div>Hi all, </div>
        <div><br>
        </div>
        <div>What are people using these days for venting a good ol' 48v
          flooded lead acid battery box? I am upgrading an off grid
          system. There is a one year old set of flooded lead acid
          batteries, so those will stay, but everything else will be
          new. I plan on using a Sol-Ark inverter. The existing battery
          box does not have any active ventilation, so I would like to
          add some. In the past, I have used the Zephyr Power Vent Fans,
          like this one:</div>
        <div><a href="https://www.thesolarbiz.com/zephyr-power-vent-fan-for-48-volt-battery-systems.html" rel="noreferrer" target="_blank">https://www.thesolarbiz.com/zephyr-power-vent-fan-for-48-volt-battery-systems.html</a></div>
        <div>They don't seem readily available, but I think I can find
          one somewhere.</div>
        <div><br>
        </div>
        <div>More importantly, what would you use to control this?
          Sol-Ark inverters do not have any kind of relay for it. I have
          found external controllers in the past (Yandina LLC Vent
          Control), but I cannot seem to find any right now. There is
          one noted in the fan documentation (Solar Converters,
          Inc. VCS1AH), but that does not seem available anywhere right
          now. Does anyone have a recommendation for either a vent fa
          controller or a whole venting solution?</div>
        <div><br>
        </div>
        <div>Thanks!<br>
          -Dave</div>
        <span class="gmail_signature_prefix">-- </span><br>
        <div dir="ltr" class="gmail_signature">
          <div dir="ltr"><br style="color:rgb(34,34,34)">
            <div dir="ltr" style="color:rgb(34,34,34)">
              <div dir="ltr">
                <div dir="ltr">
                  <table style="border-spacing:0px;border-collapse:collapse;color:rgb(68,68,68);width:525px;font-size:11pt;font-family:Arial,sans-serif" cellspacing="0" cellpadding="0">
                    <tbody>
                      <tr>
                        <td rowspan="6" style="padding:0px 10px 0px 0px;font-size:10pt;border-right:1px solid rgb(236,189,0);width:125px;vertical-align:top" width="125" valign="top"><a href="https://www.sungineersolar.com/" style="color:rgb(51,122,183);background-color:transparent" rel="noreferrer" target="_blank"><img alt="Logo" src="https://sungineersolar.com/wp-content/uploads/2019/08/Logo-Image-Only-1.png" style="border: 0px; vertical-align: middle; width: 105px; height: auto;" width="105" border="0"></a></td>
                        <td style="padding:0px 0px 0px 10px">
                          <table style="border-spacing:0px;border-collapse:collapse;background-color:transparent" cellspacing="0" cellpadding="0">
                            <tbody>
                              <tr>
                                <td style="padding:0px 0px 5px 10px;width:400px;vertical-align:top" valign="top"><span style="color:rgb(236,189,0);font-size:11pt;font-weight:700">Dave
                                    Tedeyan, P.E.<br>
                                  </span><span style="font-size:11pt;font-weight:700"><font color="#ecbd00">Owner |
                                      Sungineer Solar</font><br>
                                  </span></td>
                              </tr>
                              <tr>
                                <td style="padding:5px 0px 5px 10px;font-size:10pt;vertical-align:top;line-height:17px" valign="top"><span style="color:rgb(236,189,0)"><span style="font-weight:700">p: </span></span><span style="font-size:10pt;color:rgb(0,0,0)">he | him | his</span><span style="color:rgb(236,189,0)"><span style="font-weight:700"><br>
                                      a: </span></span><span style="font-size:10pt;color:rgb(0,0,0)"><a href="https://www.google.com/maps/search/1653+Slaterville+Rd.+%C2%A0+%7C%C2%A0Ithaca,+NY+14850?entry=gmail&source=g" target="_blank">1653 Slaterville Rd.</a></span><a href="https://www.google.com/maps/search/1653+Slaterville+Rd.+%C2%A0+%7C%C2%A0Ithaca,+NY+14850?entry=gmail&source=g" target="_blank"> </a><span style="font-size:10pt;color:rgb(0,0,0)"><a href="https://www.google.com/maps/search/1653+Slaterville+Rd.+%C2%A0+%7C%C2%A0Ithaca,+NY+14850?entry=gmail&source=g" target="_blank">| Ithaca, NY 14850</a></span><br>
                                  <span style="color:rgb(236,189,0)"><span style="font-weight:700">w:</span></span><a href="http://www.sungineersolar.com/" rel="noopener noreferrer" style="color:rgb(51,122,183);background-color:transparent" target="_blank"><span style="font-size:10pt;color:rgb(0,0,0)"> www.sungineersolar.com</span></a><br>
                                  <span style="color:rgb(236,189,0)"><span style="font-weight:700">c:</span></span><span style="font-size:10pt;color:rgb(0,0,0)"> (607) 270-0370</span></td>
                              </tr>
                            </tbody>
                          </table>
                        </td>
                      </tr>
                    </tbody>
                  </table>
                </div>
              </div>
            </div>
          </div>
        </div>
      </div>
      <br>
      <fieldset></fieldset>
      <pre>_______________________________________________
List sponsored by Redwood Alliance

Pay optional member dues here: <a href="http://re-wrenches.org" rel="noreferrer" target="_blank">http://re-wrenches.org</a>

List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org" rel="noreferrer" target="_blank">RE-wrenches@lists.re-wrenches.org</a>

Change listserver email address & settings:
<a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" rel="noreferrer" target="_blank">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>

There are two list archives for searching. When one doesn't work, try the other:
<a href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/" rel="noreferrer" target="_blank">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a>
<a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org" rel="noreferrer" target="_blank">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a>

List rules & etiquette:
<a href="http://www.re-wrenches.org/etiquette.htm" rel="noreferrer" target="_blank">http://www.re-wrenches.org/etiquette.htm</a>

Check out or update participant bios:
<a href="http://www.members.re-wrenches.org" rel="noreferrer" target="_blank">http://www.members.re-wrenches.org</a>

</pre>
    </blockquote>
    <br>
  </div>

_______________________________________________<br>
List sponsored by Redwood Alliance<br>
<br>
Pay optional member dues here: <a href="http://re-wrenches.org" rel="noreferrer noreferrer" target="_blank">http://re-wrenches.org</a><br>
<br>
List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org" rel="noreferrer" target="_blank">RE-wrenches@lists.re-wrenches.org</a><br>
<br>
Change listserver email address & settings:<br>
<a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" rel="noreferrer noreferrer" target="_blank">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br>
<br>
There are two list archives for searching. When one doesn't work, try the other:<br>
<a href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/" rel="noreferrer noreferrer" target="_blank">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a><br>
<a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org" rel="noreferrer noreferrer" target="_blank">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br>
<br>
List rules & etiquette:<br>
<a href="http://www.re-wrenches.org/etiquette.htm" rel="noreferrer noreferrer" target="_blank">http://www.re-wrenches.org/etiquette.htm</a><br>
<br>
Check out or update participant bios:<br>
<a href="http://www.members.re-wrenches.org" rel="noreferrer noreferrer" target="_blank">http://www.members.re-wrenches.org</a><br>
<br>
</blockquote></div>
<span>_______________________________________________</span><br><span>List sponsored by Redwood Alliance</span><br><span></span><br><span>Pay optional member dues here: <a href="http://re-wrenches.org" target="_blank">http://re-wrenches.org</a></span><br><span></span><br><span>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank">RE-wrenches@lists.re-wrenches.org</a></span><br><span></span><br><span>Change listserver email address & settings:</span><br><span><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a></span><br><span></span><br><span>There are two list archives for searching. When one doesn't work, try the other:</span><br><span><a href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/" target="_blank">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a></span><br><span><a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a></span><br><span></span><br><span>List rules & etiquette:</span><br><span><a href="http://www.re-wrenches.org/etiquette.htm" target="_blank">http://www.re-wrenches.org/etiquette.htm</a></span><br><span></span><br><span>Check out or update participant bios:</span><br><span><a href="http://www.members.re-wrenches.org" target="_blank">http://www.members.re-wrenches.org</a></span><br><span></span><br></div></blockquote></div>_______________________________________________<br>
List sponsored by Redwood Alliance<br>
<br>
Pay optional member dues here: <a href="http://re-wrenches.org" rel="noreferrer" target="_blank">http://re-wrenches.org</a><br>
<br>
List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank">RE-wrenches@lists.re-wrenches.org</a><br>
<br>
Change listserver email address & settings:<br>
<a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" rel="noreferrer" target="_blank">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br>
<br>
There are two list archives for searching. When one doesn't work, try the other:<br>
<a href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/" rel="noreferrer" target="_blank">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a><br>
<a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org" rel="noreferrer" target="_blank">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br>
<br>
List rules & etiquette:<br>
<a href="http://www.re-wrenches.org/etiquette.htm" rel="noreferrer" target="_blank">http://www.re-wrenches.org/etiquette.htm</a><br>
<br>
Check out or update participant bios:<br>
<a href="http://www.members.re-wrenches.org" rel="noreferrer" target="_blank">http://www.members.re-wrenches.org</a><br>
<br>
</blockquote></div>