<div dir="ltr">Good question. Voltage slowly drops in a fairly linear fashion through out the night. If it is a sudden short duration load, it is short enough that Optics can't pick it up, or it get's averaged out. When I've been on site, I didn't observe any loads that caused concern.</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Apr 19, 2019 at 11:45 AM Roy Rakobitsch <<a href="mailto:windsine@gmail.com">windsine@gmail.com</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="ltr">Using Optics, can you equate the voltage sag/ gen start command with a particular load? Or is the voltage dropping quite evenly over the course of the night? They could actually be degraded if there is no indication of a sudden load/ voltage drop. A simple load test when on site can also help you replicate and/or get a better picture of whats going on.<div><br></div><div><br clear="all"><div><div dir="ltr" class="gmail-m_361867906540137928gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div>Roy Rakobitsch</div><div><font size="1">NABCEP Certified Small Wind Installer®</font></div><div><font size="1">Certified Advanced Tower Climbing, Safety & Rescue<br></font></div><div><font size="1">Wind/PV Design Engineer</font></div><div>Windsine LLC</div><div>631-514-4166</div><div><a href="http://www.windsine.org" target="_blank">www.windsine.org</a></div><div><br></div><div><br></div><div><br></div></div></div></div></div></div></div></div></div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Apr 19, 2019 at 12:27 PM Mac Lewis <<a href="mailto:maclewis1@gmail.com" target="_blank">maclewis1@gmail.com</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="ltr">Hello Wrenches,<div><br></div><div>We recently inherited an Outback system that I've been keeping an eye on via Optics. Its a dual stack 3648 VFXR, with about 4kW of PV with a single string of EnergyCell 1100RE battery bank (reported to be ~6 months old) ~.46 kWh at C20.</div><div><br></div><div>I have been observing how the system functions and how the voltage behaves. We keep getting 2 minute voltage starts on the generator in the middle of the night that don't seem necessary judging from how much energy has been used from the battery bank. I am hesitant to tweak anything because these battery set-points are a bit different than I'm used to.</div><div><br></div><div>As per Outback:</div><div>Absorb Voltage is 55.6V for 2 hours</div><div>Float Voltage is 54.0V</div><div><br></div><div>I've slowly been dropping the 2 minute start voltage to see if there is a bottom, but I'm hesitant to take it much lower (maybe I should). </div><div>2 minute start voltage: 44.8 V.</div><div><br></div><div><br></div><div>The system easily charges the battery bank to 100% (and easily reached the 2 hr absorb time) every day. The flexnet DC is correctly set up and calibrated.</div><div><br></div><div>The load on the system is pretty consistent. They use between 400 and 600W throughout the night.</div><div><br></div><div>An average night, they may use about 6 kWh before the voltage sags below the 2 minute start voltage and it starts the generator.</div><div><br></div><div>Just curious if our 2 minute voltage needs to be dropped or if these batteries are degraded. What corrective changes can I make to get better performance?</div><div><br></div><div>I have and will call Outback about this, but I'd like other perspectives as well.</div><div><br></div><div>Thanks as always for your expertise<br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail-m_361867906540137928gmail-m_-6489060342061801899gmail_signature"><div><br></div><div><font color="#305A78" face="'times new roman', serif"><br></font></div><div><br></div>Mac Lewis<br><br><span style="font-family:"Times New Roman";font-size:medium;color:rgb(255,153,0)"><b><font face="Arial, Helvetica, sans-serif" size="3"><p align="left"><font color="#000000" face="Verdana, Arial, Helvetica, sans-serif"><span style="font-size:small"><span style="font-family:arial;font-weight:normal;color:rgb(48,90,120)"><font face="'times new roman', serif">"Yo solo sé que no sé nada." </font><span style="font-weight:700;color:rgb(104,104,104)"><font face="'times new roman', serif">-Sócrates</font></span></span></span></font></p></font></b></span></div></div></div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div><br></div><div><font color="#305A78" face="'times new roman', serif"><br></font></div><div><br></div>Mac Lewis<br><br><span style="font-family:"Times New Roman";font-size:medium;color:rgb(255,153,0)"><b><font face="Arial, Helvetica, sans-serif" size="3"><p align="left"><font color="#000000" face="Verdana, Arial, Helvetica, sans-serif"><span style="font-size:small"><span style="font-family:arial;font-weight:normal;color:rgb(48,90,120)"><font face="'times new roman', serif">"Yo solo sé que no sé nada." </font><span style="font-weight:700;color:rgb(104,104,104)"><font face="'times new roman', serif">-Sócrates</font></span></span></span></font></p></font></b></span></div>