June 29, 20197 yr Hi I'm a Newbie to PV / Solar, reading the various posts are insightful I have installed a PV system 4 weeks ago, however have something wrong with settings as we seldom make it through the night on the system as follows.: My primary goal is to be off grid. We have a gas geyser and gas stove so high amperage items are eliminated, all lights are 3 or 4w LED's 1. 9 x 325 Seraphim 325w panels 3 strings of 3 - Pic of specs attached 2. 5KV - 5Kw - SMD LynX 5000-48 - I'm assuming its an Axpert - Pic of specs attached 3. 8 x Narada 12NDT200 - 2 strings of 2 4. No additional monitoring system (Which I 'm guessing is one of my problems) - Please advise which one is most advisable to install, that will also be compatible to Li Ion batteries once I have funds to change from the lead acid to the Li Ion's My System settings are as follows.: 01-Sbu 02-50A 03-UPS 04-SEN 05-USE 06-LFE 07-EFE 09-50Hz 11-50A 12-48V 13-54V 16-CSO 23-bYd 26-56.4 27-56V 28-SIG 29-42 30-OWE 31-Sbd 32-AUE 33-EdS 34-Eu-58.4 35-60 36-120 37-30d 39-AdS Any input will be appreciated please as I don't want to cause any damage to batteries even though I know i'm cycling a battery that I shouldn't.
June 30, 20197 yr 14 hours ago, Arn said: have something wrong with settings as we seldom make it through the night on the system as follows.: I suspect that this is at least partly due to setting 31 (see below). You might also be getting bitten by the premature float bug. Unfortunately, no patched firmware is available for your model, unless it comes with a firmware version similar to 72.20 (that would mean it's a 64 V model). You should also have your battery connections checked for tightness and voltage drop. Quote 1. 9 x 325 Seraphim 325w panels 3 strings of 3 - Pic of specs attached Thanks for the pictures; they really help. Those are quite high voltage panels; certainly 72-cell. You may well have too high a voltage on cold mornings, which will delay solar production. These 145 V max inverter-chargers prefer 60-cell panels (3S), or 2S of 72-cell panels. So you might be better off adding an odd number of panels (1 or 3, 5 is possibly too much, but i think you'd get away with it), and rewire for 2S. Quote 2. 5KV - 5Kw - SMD LynX 5000-48 - I'm assuming its an Axpert - Pic of specs attached That appears to be a genuine Axpert. Quote 3. 8 x Narada 12NDT200 - 2 strings of 2 I assume you mean 2 strings of 4 modules. Quote 4. No additional monitoring system (Which I 'm guessing is one of my problems) - Please advise which one is most advisable to install, that will also be compatible to Li Ion batteries once I have funds to change from the lead acid to the Li Ion's The most common in South Africa by far, and a very good system, is a BMV battery monitor combined with ICC monitoring software, running on a Raspberry Pi. Quote 02-50A Your battery datasheet says the recommended maximum charging current is 50 A per cell, so the same per string, so you could increase this to 100 A. This will also ease the premature charge bug, because any dips in solar production that end up between 10 A and 20 A will no longer trigger the premature float bug. Quote 04-SEN I find power saving mode to be a nuisance, and leave it off. But that's up to you. Quote 12-48V This is possibly a little low for battery longevity, but it fits with your primary goal of going off-grid as much as possible. Quote 23-bYd I prefer to have overload bypass on, and I don't know why it's not the default. Quote 27-56V This is 14 V per 12 V module; this is too high. Perhaps it was a typo. I suggest the default of 54 V, though you could go as high as 55.2 V (13.8 V per 12 V module) in winter. Too high a float voltage will eventually over-charge the battery, which is bad for sealed types as you can't replace the water that is lost. Quote 31-Sbd I would turn on SbE (Solar Balance Enable); this means to allow enough solar charge current to cover the loads as well as the battery charging power. I think the only reason that this setting exists and defaults off is over caution. Yes, this will occasionally cause the battery charging current to exceed the maximum, but it's only for a brief period of time, and won't harm the battery. Quote 32-AUE As a desperation measure, you might want to try setting this to say 90, to stay in absorb charge state for 90 minutes. This is a work-around for the premature float charge bug, though it's much safer with lithium batteries, which don't boil off water with excessive battery voltage. So try the other changes first before considering this one. Quote Any input will be appreciated please as I don't want to cause any damage to batteries even though I know i'm cycling a battery that I shouldn't. You should calculate your approximate load energy by watching the load power over a day or two. You have a 20 kWh battery, of which you should only be using a maximum of 10 kWh, preferably less. Remember also that this is at the 10 hour rate; when you're running higher loads (e.g. kettle), it will reduce the effective capacity of the battery. Perhaps you just consume too much for the battery capacity. Consider replacing your fridge and freezer with high rated models. I recently replaced a 20 year old freezer, and was amazed at the reduced energy consumption. Good luck with the system. Edited June 30, 20197 yr by Coulomb
June 30, 20197 yr Author 12 hours ago, Coulomb said: I suspect that this is at least partly due to setting 31 (see below). You might also be getting bitten by the premature float bug. Unfortunately, no patched firmware is available for your model, unless it comes with a firmware version similar to 72.20 (that would mean it's a 64 V model). You should also have your battery connections checked for tightness and voltage drop. Thanks for the pictures; they really help. Those are quite high voltage panels; certainly 72-cell. You may well have too high a voltage on cold mornings, which will delay solar production. These 145 V max inverter-chargers prefer 60-cell panels (3S), or 2S of 72-cell panels. So you might be better off adding an odd number of panels (1 or 3, 5 is possibly too much, but i think you'd get away with it), and rewire for 2S. That appears to be a genuine Axpert. I assume you mean 2 strings of 4 modules. The most common in South Africa by far, and a very good system, is a BMV battery monitor combined with ICC monitoring software, running on a Raspberry Pi. Your battery datasheet says the recommended maximum charging current is 50 A per cell, so the same per string, so you could increase this to 100 A. This will also ease the premature charge bug, because any dips in solar production that end up between 10 A and 20 A will no longer trigger the premature float bug. I find power saving mode to be a nuisance, and leave it off. But that's up to you. This is possibly a little low for battery longevity, but it fits with your primary goal of going off-grid as much as possible. I prefer to have overload bypass on, and I don't know why it's not the default. This is 14 V per 12 V module; this is too high. Perhaps it was a typo. I suggest the default of 54 V, though you could go as high as 55.2 V (13.8 V per 12 V module) in winter. Too high a float voltage will eventually over-charge the battery, which is bad for sealed types as you can't replace the water that is lost. I would turn on SbE (Solar Balance Enable); this means to allow enough solar charge current to cover the loads as well as the battery charging power. I think the only reason that this setting exists and defaults off is over caution. Yes, this will occasionally cause the battery charging current to exceed the maximum, but it's only for a brief period of time, and won't harm the battery. As a desperation measure, you might want to try setting this to say 90, to stay in absorb charge state for 90 minutes. This is a work-around for the premature float charge bug, though it's much safer with lithium batteries, which don't boil off water with excessive battery voltage. So try the other changes first before considering this one. You should calculate your approximate load energy by watching the load power over a day or two. You have a 20 kWh battery, of which you should only be using a maximum of 10 kWh, preferably less. Remember also that this is at the 10 hour rate; when you're running higher loads (e.g. kettle), it will reduce the effective capacity of the battery. Perhaps you just consume too much for the battery capacity. Consider replacing your fridge and freezer with high rated models. I recently replaced a 20 year old freezer, and was amazed at the reduced energy consumption. Good luck with the system. Hi Coulomb, Thank you for the detailed feedback. Firmware is 74_30 if I have it right, I've attached a picture. Would 2s4p or 5p work, i'll just add a panel for 2s5p then which will equate to 45.15 Amps @ 91.4V It is 2 strings of 4 modules, my bad. I'll order this tomorrow - BMV battery monitor combined with ICC monitoring software, running on a Raspberry Pi and install ASAP. We have 1 energy efficient Fridge Freezer, along with an older pair of Fridge Freezer standing next to each other, I've put them on a timer to be off overnight, these are definitely the power "thieves" All our lighting is LED and we use gas for the kettle and cooking so the only two items we only use in daytime is the toaster and the oven. I'll change all the settings, monitor and give you feedback. Thanks a million for your valued input, much appreciated. Arnold
June 30, 20197 yr Author Hi Coulomb, I've changed the settings as suggested, had a look to understand why and it makes sense. Thanks again for your valued input.
June 30, 20197 yr 9 hours ago, Arn said: Firmware is 74_30 if I have it right Yes. It does mean that no patched firmware is available for your model.
July 1, 20197 yr Author Thank you Coulomb. 10 hours ago, Arn said: Would 2s4p or 5p work, i'll just add a panel for 2s5p then which will equate to 45.15 Amps @ 91.4V Would this configuration work in your opinion?
July 1, 20197 yr 10 hours ago, Arn said: Would this configuration work Yes, that's what I was trying to suggest. I did say 2S, I suppose you might have taken that as 2S1P, sorry if I confused the issue. 2S4P, 2S5P, or even 2S6P would be fine.
July 1, 20197 yr Author 1 hour ago, Coulomb said: Yes, that's what I was trying to suggest. I did say 2S, I suppose you might have taken that as 2S1P, sorry if I confused the issue. 2S4P, 2S5P, or even 2S6P would be fine. Thank you Coulomb, i'll give it a try, i'll give feedback once done. I've got lots of homework to do now.
July 5, 20224 yr Hi @Coulomb do you know what are the latest firmware for this inverter and is ther firmware where you can change setting #29 to 49v
July 6, 20224 yr 18 hours ago, Dirkie said: do you know what are the latest firmware for this inverter... I'm only aware of 74.40. [ Edit: though I have a vague recollection that I've seen a 74.50 out there. I don't have it. ] NOTE: 74.xx is triple overloaded: factory firmware with version 74.xx might be for one of three completely different models: Axpert King (overflowing from 71.xx) and the Axpert MKS IV 5.6 kW. ] Quote and is there firmware where you can change setting #29 to 49v Well, you certainly can't on factory firmware version 74.40 (48.0 V max, same as earlier PF0.8 MKS firmwares), and if they allowed this, it would require different RAM and CAN packet packing, making it incompatible (for paralleling, for example) with earlier firmware. So I suspect it's not likely to happen. However, the LFP flavour of patched firmware version 74.40e add 4.0 V to the factory setting range, so the LFP (NOT the LC flavour) patched firmware has the range 44.0 to 52.0 V. That makes the patched firmware incompatible with factory firmware for paralleling purposes. So just use patched firmware on all of the paralleled (or 3-phase or both) machines. Edited July 6, 20224 yr by Coulomb
July 7, 20224 yr 16 hours ago, Coulomb said: I'm only aware of 74.40. [ Edit: though I have a vague recollection that I've seen a 74.50 out there. I don't have it. ] NOTE: 74.xx is triple overloaded: factory firmware with version 74.xx might be for one of three completely different models: Axpert King (overflowing from 71.xx) and the Axpert MKS IV 5.6 kW. ] Well, you certainly can't on factory firmware version 74.40 (48.0 V max, same as earlier PF0.8 MKS firmwares), and if they allowed this, it would require different RAM and CAN packet packing, making it incompatible (for paralleling, for example) with earlier firmware. So I suspect it's not likely to happen. However, the LFP flavour of patched firmware version 74.40e add 4.0 V to the factory setting range, so the LFP (NOT the LC flavour) patched firmware has the range 44.0 to 52.0 V. That makes the patched firmware incompatible with factory firmware for paralleling purposes. So just use patched firmware on all of the paralleled (or 3-phase or both) machines. So will the LFD flavour of patched firmware version 74.40e work on this inverter
July 7, 20224 yr 7 hours ago, Dirkie said: So will the LFD flavour of patched firmware version 74.40e work on this inverter Unfortunately, you can't tell by looking at the label (one of my pet gripes). You have to check the range of setting 26 (bulk/absorb voltage); its maximum possible value will be either 58.4 V or 64.0 V. If the former, you need 74.40e, if the latter, you need 72.20e. I believe that if you try to use the wrong one, it won't start the firmware upload process or erase the existing firmware, so no harm is done. Not all combinations of firmware and inverter model have this safeguard, unfortunately 🧱.
August 21, 20233 yr Good afternoon, Do you know, what is the latest Firmware for this Inverter? Currently installed version: 74.50 Thank you for your Help.
November 11, 2025Nov 11 Good day i am Jan OlivierI want to know what must i do to get remote control over my inverter smd lynX 5000 via wifi
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