Abnormal Posted March 19, 2019 Share Posted March 19, 2019 Hi I have finally bought and installed my setup but I have some questions I have 1 x 5KW Axpert King 1 x 3.5KW Pylontech Setup is as follows Eskom --> 40Amp MCB --> 6mm cable -- > Axpert King 5KW --> 4mm cable --> 20Amp MCB --> RCD --> Lighting loads and fridge. 3.5KW Pylontech --> Axpert I have set up the inverter based on the settings found on the forum. Program 2 – Max charging current 30Amp Program 5 – Battery Type USE Program 12 - Back to utility source 48v Program 13 – Back to Battery Mode 51V Program 26 - Bulk charge 53.2v Program 27 - Float charge 50.5v Program 29 - Low volt DC cut off 47.5v Below are the settings which the supplier recommended. (will check them later and update in case I made a mistake) Program 2 – Max charging current 20Amp Program 5 – Battery Type USE Program 12 - Back to utility source 47v Program 13 – Back to Battery Mode 50V Program 26 - Bulk charge 53v Program 27 - Float charge (can’t remember this one might be 53v) Program 29 - Low volt DC cut off 46.5v Max load is maybe 1Kw and average load between 300W - 400W. Works well, I had previously split the DBs into different load types. I also bought a fuse for the battery (DIN rail mountable quick blow I think it is, might be 100Amp) but have not installed it yet, the Pylontech documentation did not specify for a fuse to be used. The supplied Pylontech cable end cannot fit into the fuse holder as it is meant to accept a bare cable. What’s the easiest way to install the fuse and is it necessary? (I think sounds like a good safety measure, from what I know a fuse should be as close to the battery as possible) Battery seems to charge up fine on Eskom supply but once the mains power goes out the Axpert immediately goes into fault condition 4 (Battery low voltage) but continues running like this. Seems to work fine even in the fault condition. Is there any settings that control this fault code ? seems like its built in and cannot be defined separately? This morning with the load at around 300w I switched off the inverter by pressing the button on the inverter control panel. 1st press output switched off, 2nd press inverter turned off. All went off fine, SOC on the battery reads 2 out 6 LEDs being on (so 33% available I assume) battery voltage was reading around 49v. Thought I would save the remaining battery for later. Then maybe 15 minutes later I tried to turn it on again. Pressed the button on the inverter it turns on but does not supply any power. Stays on for about a minute and then turns itself off again. Why was I not able to turn it on again? I assume there was sufficient capacity left in the battery at this point as it was not close to the 47.5v cut off. When Eskom supply is available and the battery is full I see all the SOC lights go on then they all go off again. Is that normal? I thought it should just stay lit continuously. Quote Link to comment Share on other sites More sharing options...
Abnormal Posted March 19, 2019 Author Share Posted March 19, 2019 Seems to have started up again when Eskom was back for 30 min. Quote Link to comment Share on other sites More sharing options...
SilverNodashi Posted March 19, 2019 Share Posted March 19, 2019 Rather get a fuse holder with m8 bolts. Alway use fuses in a DC system. Always. A fault on the cable could spell disaster. I am not 100% sure about the Axpert King, but the problem you describe is common with the normal Axperts as well and it helps a lot to put a monitoring system in place that can tell the inverter what the real SOC is, since the inverter's calculations seem a bit off. Quote Link to comment Share on other sites More sharing options...
Coulomb Posted March 20, 2019 Share Posted March 20, 2019 (edited) On 2019/03/19 at 7:57 PM, Abnormal said: Program 29 - Low volt DC cut off 47.5v Below are the settings which the supplier recommended. (will check them later and update in case I made a mistake) ... Program 29 - Low volt DC cut off 46.5v It might be worth sticking to the manufacturer's suggested cutoff voltage, to avoid the battery low warning (see below). Quote What’s the easiest way to install the fuse and is it necessary? As Silvernodashi said, a DC system without a fuse is unthinkable. There may be fancy electronic protection inside the Pylontech, but those can fail too. So yes, the fuse is necessary. [ Edit: of course, it has to be a proper DC-rated fuse. I don't know if these will be DIN rail mountable; they tend to be rather bulky. ] Quote Battery seems to charge up fine on Eskom supply but once the mains power goes out the Axpert immediately goes into fault condition 4 (Battery low voltage) but continues running like this. I don't think it can be an actual fault, it must be a warning. The Axperts I'm familar with turn off all relays when a fault is registered. On earlier Axperts, a warning is indicated by a "!" in a triangle symbol, flashing, and the fault LED is flashing. I believe that the King is similar. Quote Is there any settings that control this fault code ? Unfortunately, this is not documented, and I don't have a King firmware to read. On earlier Axperts, the low battery warning comes on at 2.0 V above the battery low cutoff setting (setting 29), and won't come off until the battery voltage exceeds 4.0 V higher than that setting. (Patched firmware uses 0.5 and 1.0 V instead of 2.0 and 4.0 V, but there is no patched firmware for Kings as yet). So setting 29 indirectly controls the battery low warning. Quote This morning ... I switched off the inverter ... Then maybe 15 minutes later I tried to turn it on again. Pressed the button on the inverter it turns on but does not supply any power. Stays on for about a minute and then turns itself off again. That is probably due to the battery low warning. So change setting 29 to make the warning go away, and all should be good. Though of course factory firmware doesn't have KettleKomp™ (a feature of most patched firmwares), so you may still have nuisance warnings from large loads. Quote Why was I not able to turn it on again? I assume there was sufficient capacity left in the battery at this point as it was not close to the 47.5v cut off. In its "lead acid thinking", the battery voltage was too close to the cut-off voltage for comfort. Quote When Eskom supply is available and the battery is full I see all the SOC lights go on then they all go off again. Is that normal? Are you talking about SOC lights on the battery or bars on the inverter's LC Display? If the former, I have no experience with Pylontechs; if the latter, don't pay attention to the SOC bars on the inverter. They are only roughly useful for non-LFP batteries, and are nearly useless for LFP batteries like the Pylontechs. Edited March 20, 2019 by Coulomb Quote Link to comment Share on other sites More sharing options...
Gnome Posted March 20, 2019 Share Posted March 20, 2019 (edited) On 2019/03/19 at 11:57 AM, Abnormal said: Program 12 - Back to utility source 47v Program 13 – Back to Battery Mode 50V Do you have solar panels? If not these two setting have no purpose. Your cut-off voltage is set too low as @Coulomb said, simple as that. Other than that your system is running perfectly as far as I can tell. Edited March 20, 2019 by Gnome Quote Link to comment Share on other sites More sharing options...
Abnormal Posted March 20, 2019 Author Share Posted March 20, 2019 Hi Thanks for the feedback all. Yes the system does seem to be functioning correctly. (Other than I was unable to turn it back on with little power left but thats not a concern) @Coulomb I have the low voltage DC cut off at 47.5 are you saying that it might be better to change to 46.5? Yeah my thoughts were the same would be best to ave it fused but didn't want to cut the cable to install the fuse that i have. Any suggestions as to where I could get a battery fuse with M8 connectors and some interconnector cables? I am in Randburg. Is it better to get one for each the positive and negative cables? I do not have solar panels installed as yet. Any suggestions on what to get? Quote Link to comment Share on other sites More sharing options...
Abnormal Posted March 20, 2019 Author Share Posted March 20, 2019 If I use the long Pylontech cable and connect the end to a fuse wont that mean that the cable itself before the fuse will not be protected. I know in car audio you try to install the fuse as close to the battery as possible for this reason. Quote Link to comment Share on other sites More sharing options...
Coulomb Posted March 20, 2019 Share Posted March 20, 2019 (edited) 2 hours ago, Abnormal said: I have the low voltage DC cut off at 47.5 are you saying that it might be better to change to 46.5? Yes. Quote Is it better to get one for each the positive and negative cables? No. [ Edit: but regulators may insist; see below. ] Edited March 20, 2019 by Coulomb Quote Link to comment Share on other sites More sharing options...
Fuenkli Posted March 20, 2019 Share Posted March 20, 2019 2 hours ago, Abnormal said: Is it better to get one for each the positive and negative cables I only have one fuse (in the negative cable) and our resident Pr Eng has strongly recommended that I add a second fuse in the positive cable. Quote Link to comment Share on other sites More sharing options...
SilverNodashi Posted March 20, 2019 Share Posted March 20, 2019 2 hours ago, Abnormal said: If I use the long Pylontech cable and connect the end to a fuse wont that mean that the cable itself before the fuse will not be protected. I know in car audio you try to install the fuse as close to the battery as possible for this reason. Yes, and no. The circuit will be broken. Unless those two cables before the fuse somehow manage to touch - but this is why you do a proper installation and ensure it will never happen. i.e. don't tie the two cables with insulation tape, as is common car radio installations Quote Link to comment Share on other sites More sharing options...
SilverNodashi Posted March 20, 2019 Share Posted March 20, 2019 14 minutes ago, Fuenkli said: I only have one fuse (in the negative cable) and our resident Pr Eng has strongly recommended that I add a second fuse in the positive cable. Fuses normally go on the positive side. I know, I know, electrons flow from the negative to the positive,but that's how it's been done for many years on DC circuits. A single fuse in a circuit is enough to break the circuit and protect it. But regulators want to insist on having 2 fuses. It probably makes them feel better. And besides, those 3x fuse holders sit much better on the wall than a single fuse holder, which tend to come loose. Fuenkli and Juokorow 2 Quote Link to comment Share on other sites More sharing options...
___ Posted March 21, 2019 Share Posted March 21, 2019 15 hours ago, SilverNodashi said: electrons flow from the negative to the positive That has absolutely no bearing on anything and is really just a frame of reference thing 15 hours ago, SilverNodashi said: A single fuse in a circuit is enough to break the circuit and protect it. But regulators want to insist on having 2 fuses. It probably makes them feel better. And besides, those 3x fuse holders sit much better on the wall than a single fuse holder, which tend to come loose. The reason you put in a fuse on both lines would be to avoid ground faults. Batteries are not grounded in any way (usually) so there is usually no point in fusing it twice. It also adds to the voltage drop across the cable. Quote Link to comment Share on other sites More sharing options...
SilverNodashi Posted March 21, 2019 Share Posted March 21, 2019 5 minutes ago, plonkster said: That has absolutely no bearing on anything and is really just a frame of reference thing Yes, I purely stated that since that's theoretically the start of the line, so to say 5 minutes ago, plonkster said: That has absolutely no bearing on anything and is really just a frame of reference thing The reason you put in a fuse on both lines would be to avoid ground faults. Batteries are not grounded in any way (usually) so there is usually no point in fusing it twice. It also adds to the voltage drop across the cable. I am with you on that! But somehow the powers to be, who draft these regulations don't always seem to know what they're doing. But now that you mention it, perhaps it's to cover those installations where the batteries are grounded to neutral? But, I agree, it doesn't make sense. How do you kill a dead corpse? ___ 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.