Jump to content

Vani

Members
  • Posts

    15
  • Joined

  • Last visited

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

Vani's Achievements

  1. I found this info on prolonging battery life. It seems to suggest that multiple small discharges and charges are not bad for a lithium battery and if anything can aid longevity. https://batteryuniversity.com/article/bu-808-how-to-prolong-lithium-based-batteries and this one with a snippet below: https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
  2. With Tariq's 98% SOH after 14 months, its not that bad. But i am also pretty sure that the deterioration will not be linear with time. I think Pylontech talk about having at least 60% capacity (SOH) after 10 years. So Tariq's deterioration does not seem that bad at all My system is only a month old on the batteries so it will be interesting to see the rate of deterioration based on my "ONE cycle per day" theory. The idea that a full cycle is accumulated based on percentage discharge and charge reaching a certain point seems to concur with the logic from manufacturers that claim you get more cycles if the DOD is not too low. Theoretically there could be many small discharge and charge cycles depending on the settings, amount of sun and load demand on any given day. While lithium is resilient, i still "think" the chemistry has certain thresholds that will affect stamina long term. To what extent, only somebody with some long term data can support. My gut feel is based on the anecdotal evidence of my experience with smartphones.
  3. I posted the below message on another related thread but thought i would ask here as well since there are different people conversing here and wanted different perspectives on the topic. My 5kw Sunsynk unit is basically set to 100% from 8am to 6pm. So the batteries only charge during the day when there is sufficient sun. Then discharge in stages from 6pm to the following 8am all the way down to 30% SOC. I have ticked the load priority checkbox so when load is high during the day, it stops charging the batteries for a period of time to attend to the load and blend with grid if necessary. So on a good sunny day my 7kw of batteries are usually charged by 1pm. Thereafter the PV attends to the load for the rest of the day. Not really concerned whether these settings are good or bad based on a user's circumstances, i am more interested about the way the batteries work. So in a setup, theoretically, the battery could be charged and partially discharged multiple times in the day. If the load at any point in the day demands more than what PV can supply and if the the battery has the required SOC for that time of day, the system could engage the use of the battery to power the load in tandem with PV and maybe even grid. When load demand drops, PV may get back to charging the battery. Just for context, I have 2 X 3.5KW Pylontechs (US3000C). MY QUESTIONS ARE: 1. Is it good practice to regularly charge the batteries all the way up to 100%?? Read some conflicting theories that Lithium prefers charges up to 85-90% for longevity. 2. (During the day) When the battery charges up to maybe 80% then allowed to discharge to perhaps 65% and then charge up again, is this not using up a charging cycle of the battery??? If this is true, then does it mean that multiple charge cycles are used up each day, and therefore reducing the lifespan of the battery??? With lithium batteries quoting in excess of 6000 cycles (based on DOD), the above scenario, if true, could mean that the batteries state of health (SOH) could deteriorate well before the claimed 10 years that most lithium vendors make. Any comments on the above???!!! Not sure if this has been discussed in another thread before.
  4. Hello all. Late to the party on this conversation but having a Sunsynk 5KW and some lithium batteries means that we often discover things as we go along. @bernardf posted his time of use settings. My unit is basically set to 100% from 8am to 6pm. So the batteries only charge during the day when there is sufficient sun. Then discharge in stages from 6pm to the following 8am all the way down to 30% SOC. I have ticked the load priority checkbox so when load is high during the day, it stops charging the batteries for a period of time to attend to the load and blend with grid if necessary. So on a good sunny day my 7kw of batteries are usually charged by 1pm. Thereafter the PV attends to the load for the rest of the day. Not really concerned whether @Bernardf's settings are good or bad, i am more interested about the way the batteries work. So in his setup, theoretically, the battery could be charged and partially discharged multiple times in the day. If the load at any point in the day demands more than what PV can supply and if the the battery has the required SOC for that time of day, the system could engage the use of the battery to power the load in tandem with PV and maybe even grid. When load demand drops, PV may get back to charging the battery. MY QUESTION IS: When the battery charges up to maybe 80% then allowed to discharge to perhaps 65% and then charge up again, is this not using up a charging cycle of the battery??? If this is true, then does it mean that multiple charge cycles are used up each day, and therefore reducing the lifespan of the battery??? With lithium batteries quoting in excess of 6000 cycles (based on DOD), the above scenario, if true, could mean that the batteries state of health (SOH) could deteriorate well before the claimed 10 years that most lithium vendors make. Any comments on the above???!!! Not sure if this has been discussed in another thread before.
  5. Any ideas on the "Activate" checkbox below all the battery types. As i said, mine is off but the batteries work and behave as expected.
  6. Just wanted to find out. When connecting the Pyontechs US3000c to the Sunsynk 5KW. I selected the lithium option under battery settings as well as CAN option and BMS_Err setting. All seems to work fine and also noticed the perceived pause at 89% when charging. 1. On the page where lithium is selected, at the bottom left what is the Activate checkbox for? mine is unchecked but still works fine. 2. Does it matter what the Float, absorption and equalisation are set to? Or does the BMS handle everything . Even though i suspect it is not being used, mine is set to : Float: 51.8V absorption: 52.5V equalisation: 53V (I also understand that equalisation is more for lead acid type batteries)
  7. Hi Please refer me to a retailer where i can get this solar assistant Pi system. Sunsynk is also talking about a new logger due to come that will also allow settings changes in addition to monitoring. Not sure whether to wait for that to hit the market.
  8. Hi. My data logger has been going intermittently offline every now and then. I press the button on the data logger for about 5 seconds and it usually resolves. Sometimes it takes an irregular sequence of button presses to resolve. I tried connecting directly to the logger to check/re-do the Wi-Fi it is connected to but it still disconnects after a while. I have not changed any electronics around the logger that could create some RF noise. Worked well for over a week and then disconnected about 4 times this weekend. Has anyone had this problem and any resolutions?
  9. Hi. Thanks for the feedback. From your opening statement, i assume that you are saying that my plans will work as described. Just checking as you answered "Yes" to my 2nd question. Just for clarity. You dont have to use both MPPT chargers. It will still work if just one is connected?
  10. I have a Sunsynk query but will give some background prior to the queries. I already have 4 X canadian solar 415W panels with a small 2.4Kw inverter. I want to upgrade the inverter to the Sunsynk 5KW without any batteries for now. Batteries and more panels will come later. Below is the spec of my panels. My queries are as follows: 1. Will the inverter work with just the 4 panels and no batteries installed? I understand the scenario when solar and utility are off. 2. I only plan on using 1 of the two MPPT controllers. Will this be a problem?
  11. i got the serial to usb cable. Installed the driver through device manager. Not getting any life from the inverter though. The application does see the new com port but no data coming through at all. Also tried allowing SNMP trap through the firewall but no luck. Anyone with any experience here?
  12. Hi Just a query on the WatchPower application for PC. My inverter unit came with only an ethernet port. The cable is ethernet to female serial (RS232). I now need to get a male serial to USB as many computers dont come with RS232 anymore. Does anyone have experience of this working or not with the additional cable? Tried a normally wired ethernet cable but did not work. Does anyone know if an ethernet crossover cable will work directly from inverter to PC?
  13. 1. I set the battery type to user defined and it seems to have solved my high voltage issue. It now reaches the default bulk charging voltage of 28.2V and does not go beyond that. 2. i am going to change the DC cut-off to your suggested 23.7 and monitor it from there 3. I have set the max utility charging to 20A which is the lowest on this unit. 4. No other info on the menus about PV current. I am going to try a DC clamp meter. 5. It was always my plan to go for one more 415W panel Thanks very much for the information. Very helpful indeed.
  14. I have recently installed a 3kva/2.4KW Open Range Solar inverter. My aim was to create a temporary backup system. Probably an Axpert brand. I have 2 X 105Ah (2 X 12V = 24V system) batteries, flooded lead acid. Before i installed the panels the utility line charged the batteries to about 28.2V and then floated at 27V until there was a load again. To get max life on the batteries i made the following settings. Setting numbers on my inverter indicated as well: 1. Source priority is set to Solar 5. battery type is set to Flooded lead acid 11. Max utility charging is 30A (Default) 12. Voltage point back to utility is 24.5V (Dont want DOD to go below 50%) 13. Voltage point back to battery is 27V (Default) 26. Bulk charging voltage is 28.2 27. Floating charging voltage is 27V (Default) 29. Low DC cut-off voltage is 24V (Again to save the battery) I notice that solar charges the battery up to 30.4V and then hovers there for quite a while until battery is required again. Is 30.4V too high to charge the batteries up to??? My solar charger can handle a max of 80V and 50A. I have two 415W canadian solar panels. Input Voltage ranges from 25V to about 40V as they are wired in parallel. Going to add another panel so that the battery is not utilised as often as it is now. My hope is that the solar will cover a max of 500W demand during the day. I have no way to check what amps are coming from the panel as the inverter only shows input voltage and not amps. So my questions are: 1. Is 30.4V too high for the batteries when charged by solar 2. How else can i check what amps are delivered from the panels. 3. Other than the solar charger max of 80V and 50A, Is there any maximum for the number of Watts that can pushed to the inverter? I want to add a few panels and want to try and work out the ideal configuration without going too close to the maximums. Any responses will be appreciated.
×
×
  • Create New...