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Thank you for the great forum, Safe Driving over the weekend. Sincerely Jason

NickNou

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  1. One could consider this, but most of the local relays that I've had a look at have time delays starting at 0.5 seconds and up. With my current prepaid meter, the trip occurs almost immediately. It would be great if you could dump the spike into a set of immersion heaters or similar.
  2. I'm currently running with 2.08-13. I did see yesterday that the 2.08 is out as a official release. Changelog does indicate that rev 13 includes the change for the 200W fronius zero feed bug. I'll flash with the release version of V2.08 this weekend. I'm not running with a grid meter, and currently make use if the monitoring inside the Quattro itself. The Ecolec 570 was discontinued ages ago. There is little/no documentation available, and all the info I've been able to attain hasn't been of much use. I do know that the Ecolec is fitted with an internal RCD monitoring circuit, where you can configure the earth leakage trip. I thought this might have been the issue, but I saw tonight that the Earth leakage protection on my specific meter is disabled (You can select from OFF, or in the range of 10-300mA I'm going to endevour and have the ECOLEC swapped with a BEC23. Might take forever with my local utility. I've heard from other installers that the BEC23's meters are not that forgiving, so I dont know if I should be considering other options. Nevertheless, you can do alot with a reverse feed trip based on 40W over 15 second window. The Ecolec trips almost instantly (less than a second after I remove the load) and its been a problem here before. This is true. The ESS controller does overshoot, but settles very quickly. Even though I have meter issues, I must say that ESS does have a very well tuned control loop.
  3. Have some more time on my hands to test the ESS system again. PV modulation: Modbus throttling of the Fronius works just fine. With no or little AC load, the Fronius is throttled to very low outputs quite effectively. This works quite well even when disconnected to mains. As a redundancy, I checked how well the frequency shift would work in the event of modbus failure. Victron disconnects from grid connection, and immediately starts with frequency shift modulation, pushing frequency up to around 52.7Hz. Fronius scales back PV output accordingly. No problems here. Reverse power spikes: Still have a problem with this. A typical example of a trip I had this morning: AC load: 3000W Battery discharge - approx 800W into system PV input +- 2150W Grid power - +-150W AC loads drops to 1200W due to large load switching off - Mains drops out on the Pre-paid. This is the major issue I have on the ESS setup. Still looking at the various options I have available. Off-grid Fronius trips: With the grid disconnected, the Fronius disconnects from the Victrons output every 3-5minutes, or each time that a Large-ish load connects or disconnects from the AC-output. All trips are of type 453, and are due to short term voltage variations on the AC line. Will most likely need to change some of the grid tie settings of the Fronius to prevent this.This is not really an issue when the system is running in parallel with the grid, as the mains connection keeps the system voltage stable.
  4. ACDC have the SP510 available, Rhomberg. I don't think this unit would be quick enough to respond to a sudden reverse power feed. You can only set the response delay between 1 and 10 seconds. Measurement is also not that accurate. On a 5A CT you can measure down to 100mA. Say you have a 60/5A CT on the line, you getting a sensitivity of 600mA. Rough maths puts that at around 130W. Not really great. I'm sure a bit of googling will reveal purpose made monitors for this sort of application. Already running the 5kVA Quattro with a maximum inverter limit of 3000W. I think a big factor here is that the PV is being fed directly into the AC -Output by the Fronius. Even if the Victron can react fast enough (i.e in the case where there are charge controllers feeding into the DC bus) and avoid trips, it still needs to absorb the incoming PV from the Fronius, or modulate power over modbus. All this takes (too much) time! Will most likely be be simplest option here. But I need to get feedback on which meters are the most forgiving (Conlog, itron, Landis...etc) in absorbing the occasional reverse power spike. The 15 second window on the conlog BEC23 is workable, as the control loop to regulate the output of the Victron does over and under shoot, as you stated above.
  5. Ditto the above. Once had my Victron box make extremely odd noises and could not figure out why. Checked everything (PV inverter, frequency shift, charging voltages) but could not make sense of why the inverter was resorting to a complete buzz-out with almost no load late one afternoon. DC voltage was also a little erratic. Turns out this happens each time the wife uses her hair straighter... as per plonkster, a non-linear current form is most likely to blame.
  6. Hi Gents, Been tinkering on-off for a long time, but I finally managed to get a Victron ESS system up and running on my domestic system over the weekend. In principal, my ESS setup consists of the following: Victron Quattro, 5000VA Fronius 3.5 Primo grid tie inverter (on inverter output) 48V-825AH Battery bank BMV 700 Beaglebone Black (Venus GX) managing the whole lot I used to run the setup with a SMA SB4000 in a hub 2 configuration. Performance with this was slightly lacklustre, as the Multi/Quattro spends most of its time not connected to the grid to perform the frequency shift on the SMA. I hence decided to embark on the ESS route.... Commissioning: Setup of the ESS is done as per the Victron manual - Easy to follow if you have all the bits. The system is quite intuitive to setup. Started the ESS system up too late in the afternoon to see if Venus GX could actively modulate the power output of the Fronius. After topping off the batts, the system settled into a absorption charge, and stayed there for the rest for the afternoon. Primary PV power modulation is done by Modbus TCP. If this fails, I'm assuming the Victron should disconnect from mains, and make use of frequency shift control. Switching of Large loads and pre-paid meter trips: Don't need to remind anybody here about the rigors of reverse power on prepaid meters. This is one shortfall I'll still need to tune out. Tested the ESS system with a 2kW kettle on the AC out. This is were ESS really shines (for a brief moment). The system allows the grid to supply the brunt of the initial full load. Gradually, the ESS system works down the amount of power being drawn from the grid and supplements this from either battery and/or PV power, up to a set maximum. Works very well - until the load is switched off. At this point the ESS configuration can't react/modulate fast enough, which sends a reverse power spike into the mains connection. Although very short, this is enough to trip the prepaid meter. Perhaps somebody has had similar experiences? I recall Plonkster posted about this (Hub-4) a while back. My prepaid meter is a old Ecolec 570. I'm assuming I might need to have my meter swapped out and replaced. Is there a prepaid meter available that has a reverse power policy that is slightly better suited to this type of issue (i.e reverse power is determined over a time spans of 10-15 seconds)? Some discussion here - http://powerforum.co.za/topic/816-inverter-tripping-prepaid-meter/ Even a prepaid-meter that has Significant Reverse Power metering, and decrements credits for the minor reverse power events that occur would be OK. Landis GEM perhaps? Would appreciate some suggestions. I could set the grid set-point higher to allow more modulating margin for switching of big loads, but I don't want to be pulling unnecessary power from the grid if I don't need to. Even with this set at 50W, I'm getting meter trips when switching off large loads. I read somewhere that the rate of change of the ESS configuration is set at 400W/s. Perhaps this should be quicker? Mains re-connection: Each time the Quattro re-synchs to mains and connects, the Fronius disconnects and runs through its grid tests. I think this has to do with grounding of the neutral line of the inverter installation, were it momentarily hovers un-grounded during mains re-connection for a very short time. The Quattro does have an internal grounding relay that connect the outgoing neutral to earth during inverter operation and opens when the unit reconnects to mains. A hard wired N-PE link on the Inverter AC bus might help here, but this might* not necessarily be compliant. Anti-Islanding protection: Only doing this capital-expenditure once the system actually works. Also, Big thanks to Plonkster who provided me with a development version if Venus GX (2.07) a short while ago with his serial starter patch for the mk3-usb. I've since updated to a development version of 2.08. Really worth while. Nick,
  7. Plonkster, Thanks a million for the updated image for the BBB - greatly appreciated!! I flashed the new image, and the Mk3-USB to VE interface was pretty much plug and play. I'm getting figures from my blue box, and the info is pushing through to the VRM. Is the objective here to have Venus capable of reading and logging consumption of simple pulse metering devices?
  8. I see the file size topped out . Busy downloading. I'll flash with the new image to the BBB tonight and see if I win! Thanks again
  9. Thanks a lot - greatly appreciated! FYI - Did a bit of Googling on why I'm sitting with a Fronius Primo with no data manager card. After scouring through the Fronius fine print, It seems they have two specs - a Full spec and a Light spec. Light spec has the Data manager card omitted from the scope of supply. Alas... I'm sitting with the light variant. I'll have to retrofit a card - Not that happy, considering I'm normally quite thorough with this sort of thing.
  10. Let me see where this takes me - I have the whole evening left to tinker.. That would be great - I'll follow up with you if I don't come right using your input above. Thanks!
  11. Hi Plonkster, Thanks for the quick feedback! I'll give it a try... Like I said, this is not my core area of expertise, hence the question. I'm quite sure I'll make headway if I get into it. Ran into a bit of a dead end with my Fronius Primo. I understood these items were distributed with the datacards already installed - they are marketed as Fronius' communication based inverters. Seems I've been supplied what seems to a variant without the data-manager card.... Thanks again, Nick
  12. Hi Plonkster, I know you've been working on the Venus/Raspberry Pi these past few months. Hoping you can assist... I'm busy trying to get ESS running on my setup, and am running the Venus CCGX image on a Beaglebone. I have the BB connecting to the VRM, and I haven't had any issues connecting my BMV, via a USB-VE Direct cable, to the Beaglebone. Now, I'm trying to get comm's setup between the Beaglebone and the Quattro. This is being done via a MK3-USB. I know i need to follow the instructions, as per the instructions on github: modify the /etc/venus/mkx-port file: change the listed tty for the ttyUSB in use by the MK3-USB remove the -i flag from /service/vecan-mk2/run How do I go about doing this? Do I need to use a specific IDE of sorts? Please advise,,, Apologies if this is a trivial/basic question - This is not my forte! Back to installing the Fronius for now.... Nick
  13. True - this will greatly simplify the installation. However, I wont be surprised if most installations going forward make use of regular Multiplus and Quattro inverters regardless, even if the Multigrid is available. From a cost standpoint, Anti-islanding add-ons just don't make any sense. An uninformed consumer won't be willing to pay R7.5k for a small blue box to comply with regulations that they might not even be checked on. Its a very difficult "concept" to sell, even at 130 Euros... Personally, I feel that if installers and wholesalers were concerned with the above, anti-islanding devices would be readily available locally, at a reduced cost. Quick reading of NRS-097-2-1 states that two disconnection devices are required, of which one must be electro-mechanical and the other can be solid state. From your points above, its clear that the Multi-plus has sufficient monitoring capabilities to perform the anti-islanding. It's a pity that the Victron can't be configured (firmware, VE configure assistant) to use one of the auxiliary relays to control a contactor as a second isolation point - this would effectively also disconnect the measurement points that actually do the monitoring. I thought I was onto something there... Surely all installations - regardless of when they were installed and approved, need to be maintained to current requirements and standards? Even on old Hub-2 configurations, the system could be configured to export surplus solar.
  14. Quite interesting - There has been ample discussion on the topic of anti-islanding these past few months. Fact remains - any South African ESS install will need a UFR 1001E to be compliant. No self-engineered arrangement of contactors, coils or relays can forgo this. Pricing and lack of local stock holding of anti-islanding units are part of the problem, and lends itself to the large number of non-compliant Victron installations, many of which are blissfully pumping surplus PV through old mechanical meters. For interest: There are other options - with VDE certifications - which are better suited to very large PV plants. They are marketed as mains-decoupling relays. These include the DSE P100 from Deepsea Electronics, and the Mainspro unit from ComAp. These are not really applicable to small scale embedded generation, nor do they have NRS certificates...
  15. As discussed earlier here - Regulations will require an external anti-islanding device which manages your Multiplus' connection to the grid. In the case of the UFR 1001E, the device energises or opens an external contactor to disconnect your "embedded generation" from the grid. A 2-pole AC isolator or breaker would not fulfill this purpose. Plonkster uploaded a photo of his UFR 1001E box a while back - http://powerforum.co.za/topic/1134-complies-with-local-nrs-097-2-1-regulations/. going off his posts, The one relay contact (K1) manages the Contactor coil to switch the connection to the grid - I'm very sure he'll confirm if this is correct. I'm in the process of getting my kit together to reconfigure my Victron for an AC-coupled ESS setup. A little UFR 1001E, or any other certified unit, is a very expensive, but required, part of any ESS install. They are almost impossible to get hold of locally. Nick
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