Roentgenzap

Hi Beat I want to Main inverter to use LiB - that way the BMS / BMAC can more efficiently (well, supposed to) regulate the charging, etc. The minimum discharge voltage according to the battery documentation is 48V. So I cannot go any lower than that - that is why the value is fixed in the LiB program. The benefit is accurate SOC information. The Axperts are dismal at SOC estimation when just using voltage parameters / USE setting. I know I can look at the BMAC for the SOC, but would like the SOC and charging info passed on to the inverters in order to better control with ICC. I can then use SOC as control between SBU and SUB. Hopefully, today so far no error messages since I have changed setting 12 to 2V above setting 29. Let's hope for the best

Dear All, My current setup: 3 x Axpert King 5KW (Full Circle Solar) in parallel (Firmware 71.97 + 02.66) 1 x Bluenova HC 37.5 Lithium 1 x Bluenova BMAC 28 x 370w panels (string 2sx5p X2 + 2sx4p) ICC 4.9 on Pie I recently upgraded from 16 x Narada AGM batteries (+Victon BMC 702) to the BluenovaHC battery. Removed the Victron BMV 702 and replaced with Bluenova BMAC. Current connection: 3 x Axpert inverters in parallel (single phase) - correctly setup with 1 x HS and 2 x SL Bluenova HC connected to BMAC via RJ45(battery) to BMS CAN port on BMAC BMAC connected to master inverter via RS485 (BMAC) to battery port on inverter with correct wire (pinout 1->5;3->3) ICC via USB running from one of the Slave inverters. Master inverter set to LiB, Slave inverters set to Use. Inverters running in SBU setting. There is successful coms between BMAC and Master inverter as the battery icon is flashing (and also on the 2 slave inverters ==> so most likely successful pass-on from Master) I keep on getting intermittent Error 61 / Connection errors on the Master inverter. Randomly, I am also experiencing low voltage (04) errors, although the battery voltage is fine and SOC on battery display is 80% or above. The BMAC does update the charge settings of the inverters (Max charge current, float, bulk, etc) - curiously, these values are different from the proposed values in the battery manual. Bulk and float is set at 55.2V and cannot be changed when in LiB battery setting. Also Low DC cut-off value is fixed under the LiB program to 48V (I presume this comes from the BMS / BMAC) I have manually set parameters: 12 = 50V (to comply with FAQ rule 2 => set value 12 to 2V above 29) 13 = Full I cannot explain why I keep getting the 04 / low voltage warnings. Also, communication error (61) also appears intermittent. I noticed error 04 especially late afternoon when PV was dropping and PV values below supply for the house. The battery was 100% charge. Battery warning would only occur if BMAC was communication with inverters. When Slave 1 + 2 was not showing BMAC communication, the also no error 04 (low battery voltage) warning on Slave 1 +2, even when the Master was showing error 04. It would seem that the BMAC is somehow passing the wrong battery voltage to Inverters - although battery voltage values in the BMAC monitoring page appears stable and well above limits. Sometimes the errors would resolve spontaneously, but a couple of times the inverters went into bypass mode due to low battery error. Any insight / advice would be much appreciated.

Hi The SBL / SLB setting is separate from the operating mode (SBU / SUB) in the Kings. You can have either SBL or SLB enabled and operate in SBU or SUB mode. Hence my confusion. That may be the case if operating in SUB mode. With the Kings ability to blend AC/PV/Battery power, does it make a difference though? if (PV power) + (Ac power) = Load + battery charge, does it matter where it each one is assigned to, as total power usage will be the same? The only impact I can forsee in this circumstance would be the charging rate (limited to PV availability). If operating in SBU mode, then there will be no AC usage unless battery voltage is below cutt-of or back-to-grid voltages. Should PV power be insufficient for loads, then battery will be consumed until battery cut-of value or back-to-grid voltage has been reached. Once again, this would only be if operating in SUB or USB mode. So if I re-hash this, then operating in SBU mode (and given that the battery voltage is above back-to-grid and cutt-off settings), then SBL / SLB will basically be the same. Only when operating in SUB mode, then SBL / SLB comes into play when consuming utility with impact on the battery charge rate (depending on PV availability). This obviously is further confounded when taking the UCB / UDC setting (and max AC charge rate setting) into account.?

Thanks Coulomb I can report that the rewiring was done and the PV drop-out issues I was experiencing, is gone. Also, battery charging on PV seems much better now. Thanks for the help!

Hi All, So, my setup: 3 x Axpert King 5Kva in parallel (working as single phase) (Firmware 71.9) 16 x Narada 200ah batteries (Narada 12ndt200) setup in 4 x 48V parallel. 28 x 370W panels (2s14p split 5/5/4 between the inverters). My question relates to setting 16 - Solar energy priority on the Axpert King. Options for this setting: SBL / UCB - Solar energy for battery first, Allow utility to charge (default) // SBL / UDC - Solar energy to battery first, disallow utility to charge // SLB / UCB - Solar energy for load first, Allow utility to charge // SLB / UDC - Solar energy for load first, disallow utility to charge Now I fully understand the functionality to enable or disable utility battery charging - that makes complete sense. The problem I have is between the SBL and SLB settings - what difference does it make in practical terms? When PV power is more than load, the batteries will charge with the excess power available (no matter SBL / SLB option). When PV power is not enough to supply load, then the shortfall will be taken from the batteries or grid, depending on operating mode setting (SBU or SUB respectively). From what I can see, what difference does the SBL / SLB setting make, or am I missing something?

Hi All I recently installed 3 x Axpert King 5kva inverters in parallel (single phase). Panels are 27 x 370W Renewsys. Battery running 16 Narada AGM in 4 x 4 config. Also using Victron BMV-712. All monitored by ICC on Pi. My inverter specs for each inverter: Maximum PV Array Open Circuit Voltage 145 VDC Maximum PV Array Power 4000 W MPP Range @ Operating Voltage 60~115VDC Maximum Solar Charge Current 80 A Maximum AC Charge Current 60A Maximum Charge Current 140 A Panels are rated at: Rated power (Pmax), Wp 370 Max. power voltage (Vmp), V 39.94 Max. power current (Imp), A 09.28 Open circuit voltage (Voc), V 49.12 Short circuit current (Isc), 09.80 A Module efficiency (%) 19.14 Currently, panels are wired in 3 series x 3 parallel per inverter. Is that the optimal configuration? Theoretically, that is about 10kw setup (9900w to be precise). I never however see close to that during the day. The maximum I have seen recently is about 5800W coming from the PV panels (between 11am and 1pm) - and that is with sufficient load from the house (4500W) and also batteries charging. It just seems somewhat low. I understand that 370W rating per panel is theoretical and real life rating (NOCT (Wp) at 45 ± 2 0C @800 W/m2) is at 275W - even then, I should be able to get closer to 7500W from the panels. Secondly, my current inverter settings is set at 50A PV charge (per inverter) and 40A AC charge (per inverter). Even with available PV power, the PV battery charging never goes above about 60A in total. Am I missing something here? Any help would be much appreciated!

Hi Coulomb, Thanks so much for the detailed answer. Ok, so from what I understand from your link, is that the Float bug occurs when the charging amps drop for more than 50 sec below (Max charge Amps /5). So if we set the max charge value as low as reasonable, this should (at least partially) negate that occurring. For instance, when Max charge current is set at say 50A per inverter, the float bug will occur when the charge current drops to below 10A for 50 seconds. But if set at 30A per inverter, this will only occur if the charging current drops to below 6A? The trick would be to get the max charge amps as close as possible to the realisticconstant achievable amps on that PV string per inverter. I see that there is patched firmware out version 71.80 - would you recommend using these instead of the 71.90 I am currently on? If I use this feature, what would a reliable setting time be? Is there still some form of monitoring in this stage to decide when to exit the Absorption state or is it purely time based? Thanks again for the help!

Dear All I have browsed though the forum, and as a newbie, I have to declare myself confused! As first disclaimer - I am a novice to solar with basic understanding of battery principles. So, my setup: 3 x Axpert King 5Kva in parallel (working as single phase) (Firmware 71.9) 12 x Narada 200ah batteries (Narada 12ndt200) setup in 3 x 48V parallel 27 x 370W panels on the roof. Spec sheets of the batteries which states equalize and cycle voltages of 2.35V - 2.4v and float of 2.25V. Maximum charge current of 50A. I am concerned that my batteries are not being fully recharged. When working in SBU mode, as soon as PV cannot supply house demand, the battery volts will drop about 51.5V. During the night the house load is about 750W - with the morning battery volts at about 48.5V. I am still getting to grips with the system, but I am worried that they do not stay at absorption charge not long enough. Looking at the battery voltage graphs, would stay in absorption voltage of 56.4V for about 1 hour, sometimes less. Initial setup by the installer was set at: Bulk charge 56.4 Float 54V Low DC cutoff at 42V. Back to grid charging voltage 46V Max PV charge current 60A (that is combined across the 3 parallel banks, so in effect 20A per bank as I understand). Would a more appropriate setting not be: Bulk charge 57V (halfway between spec levels) Float at 54V Low DC cuttof is far to low for me. I would think something like 47V (thats about 40% SOC) back to grid at 48V Should the PV charge amps be upped to 90A (that would be 30A across each parallel string). I am looking into installing a BMV-712 to get a better understanding of battery SOC and usage. Any advise would be highly appreciated!