Roland you know more about electricity and electronics than anyone ive ever had the chance to have conversation with. Can i ask you sir where you became so educated in this? Its rare to find somone that knows so much qbout this but you are the only person thats on here teaching people and helping them. Thankyou for what you do. The world needs more people like you

@RolandW_DIYEnergyandMore

Жыл бұрын

Matthew. I have graduated as electrical engineer but then actually went to fly airliners :) As I built my own holiday resort in a country where nobody cares if you hire electricians to do your jobs, I had my playground to do it all by myself and use standards which they would not even know of here. Several years ago, when I started with my PV systems, I noticed that there had not been any publicly available information about grounding issues once you are starting to mix up inverters and grid. I knew that many DIYers would still do such things by themselves, so I just wanted to raise the awareness that DIY still must use safety standards as they can harm themselves or their loved ones if certain things are done the wrong way. At least I want to confuse people so much that they start to educate themself before they do something terribly wrong. Bless you buddy, thanks for watching my videos!

Excellent video Roland. Back to the roots ☺️

Good video. Just on the example at the end. Whilst it provides isolation between the PV string and the AC side. Im not sure it provides isolation between DC and AC. The transformers here appear to be operating as an isolated DC/DC converter, which is then fed into a non-isolated DC/AC converter. So under single fault conditions it would be possible for it to feed the output with DC current. This can cause no end of problems for other equipment. Especially when AC side transistors misbehave - which they obviously do. Preferably an inverter would notice this and go into fault mode - but obviously many are poorly designed and don't.

Great video! Keep up!

Thanks a lot for the video. It appears that apart from cost, the best thing to do in order to clear all doubts is to go with a type B RCD. Could you please do a video on the best ways to properly ground solar PV systems (off-grid and grid connected).

@RolandW_DIYEnergyandMore

2 жыл бұрын

Hi, thanks for the comment. Yes, if cost is no factor, just go with a Type-B RCD. Grounding of Grid-Tied systems is pretty straight forward. A Grid-Tied Inverter is similar to any other appliance. Just connect to the existing Grid installation Ground from the main panel. You are not allowed to create a new different Grounding point for an On-Grid inverter. For the Off-Grid Grounding there is already a video about "Grounding and N-G bonding in a simple Off-grid System". kzread.info/dash/bejne/l4Vlq9asoNyfkbA.html Please watch it for reference. Thanks

hi , very nice video , could we got the document because it is hard to follow and to read it?

@RolandW_DIYEnergyandMore

Жыл бұрын

www.se.com/ww/en/download/document/998-2095-12-31-13AR0_EN/ think this should be what you need...

Here in Australia we also have few companies that make Residual Voltage Device. Similar to RCD, but its checking voltage and current between ground and forces RCD to trip if it detects current to ground. Is there a mainstream product available or its a local "know how"?

@RolandW_DIYEnergyandMore

3 ай бұрын

Australia uses all the same devices as the other 220-240V 1-Phase, 400V 3-phase countries and regions. There is no local difference for RCD, RCBO, etc. They are all working on the same principle.

Hi and thanks for this video, I'm a little confused here,I have off-grid type inverter, with grid connected to inverter when there is electricity from utility company,should I put the type B RCD after the inverter or before the inverter ?

@RolandW_DIYEnergyandMore

Жыл бұрын

RCDs are always ment to be installed after the power source at your breaker panel. Upstream RCDs at inverter AC-In can cause problems if there is a downstream N-G bond present either inside your inverter or in your panel. If your installation requires a Type-B RCD depends either on your loads or if your inverter is transformer-less type as explained in the video.

I know a lot of the inverters we buy in the USA are actually not recommended for use here and we cannot get the approved to be legally used. Only a small amount of inverters are able to be permitted and legally used. Most people just use those type as off grid and never have them connected to utility grid.

@RolandW_DIYEnergyandMore

Жыл бұрын

Yes, it's a wise decision to stay purely off-grid when possible or at least design your system to switch over with complete separation. The US split phase system is introducing a few more challenges into the topic anyways, especially when people are starting to use European and Chinese standard equipment.

What is RCD in solar system? A Residual Current Device (RCD) is used to detect these currents and disconnect the circuit from the source automatically when the values of these residual currents exceed the pre- defined limits.

@RolandW_DIYEnergyandMore

2 жыл бұрын

Yes, DC leakage into AC (like using the backdoor), that is the relatively new topic only relevant for solar systems... and this can only be dealt with by Type-B RCDs. But as said, the Inverter must be a "transformer less" design

Hi Roland, the micro inverter you own, did you find a FET of higher current and would an auto grade Japanese FET of higher current be an option? And aluminum capacitors.? I thought about externally mounting a fan to cool the heat sinks inside a marine aluminum weather resistant hood like computer graphics card cooling designs. My like for your inverter is the low ac voltage . I will be fitting RCBO units on output side of each panel invert for full safety along with lightning protection. 500v dc scares the hell out of me. Andrew the Electrician Thankyou for you micro inverter video. Buying the micro inverter 2500w. 4 panels input. Andrew Nz

@RolandW_DIYEnergyandMore

Жыл бұрын

Hi Andrew. Those WVC inverters have so many issues. I see it on other YT channels that they do have a variety of many different faults. I don't think it makes sense to "improve" it component wise. Just don't use any of these. High voltages are always a bit scary, but usually the DC side is always nicely isolated to ground so chances to get really hurt are manageable. I still once managed to touch both the + and - on 120V DC. Yeah, it felt like 230AC, haha. Greetings to NZ, Roland

@aandscrawfoski

Жыл бұрын

@RolandW_DIYEnergy Thanks Roland, I may have to find a circuit design, and free geber file with open source software available, maybe a pi zero with wifi and a galvanic trans former design and build a pcb in China with over rated auto grade components. Appreciate you videos . From Andrew Nz

Hello again Roland, quick question: What model and amp capacity were the FETs, please? And did you swap them out for Japanese FETs or Texas instruments FETs. Reason for question. Can't find any substitute for 4 panel input with 2000w output 230v 8 amp units. Thank you for your patience From Andrew Nz

@RolandW_DIYEnergyandMore

Жыл бұрын

Andrew, the WVC had the IRFB4110 built in. I ordered replacement from China via AliExpress. If you can get better ones then its surely worth a try. Deye for example is selling micro inverters too. You would have to contact the seller via Alibaba: m.alibaba.com/product/1600549910549/Deye-Solar-Inverter-Single-Phase-4.html?s=p Those are brand inverters at least and they will have good components built in. Cheers

@aandscrawfoski

Жыл бұрын

@RolandW_DIYEnergy Thanks mate your awesome. B series RCBO show was fantastic for defending electronic equipment on a solar system. Thanks for sharing your engineering knowledge. God's speed Andrew Nz

@RolandW_DIYEnergyandMore

Жыл бұрын

@@aandscrawfoski they are actually also selling the Deye 2000W microinverter on AliExpress: THB 8,800.32 38%OFF | Deye 2000W G3 INMETRO VDE IEC Grid Tie Solar Inverter With Limiter 4 MPPT IP67 With Built-in WIFI, 20-60VDC 220V-240VAC 50/60Hz a.aliexpress.com/_msuibBa You can get some infos there. Cheers

@aandscrawfoski

Жыл бұрын

@@RolandW_DIYEnergyandMore Thanks Roland, have a fantastic day.

Hi, what would you suggest to do if you have a transformerless inverter that trips a 30ma rcd when the solar panels get wet? (the rcd that is tripping is on the utility input side). I have an 30ma rcd on the ac output side, and this does not trip. The inverter is off grid hybrid with utility input bypass. Would you just use a 100ma rcd? Or is it possible to use two 30ma rcds in parallel? Thank you 👍👍

@RolandW_DIYEnergyandMore

Жыл бұрын

Hi. Actually the utility IN for bypass, belongs still to the TN Grid, so you have installed a RCD upstreams of another power source. The first RCD should be installed inside your main panel of your installation. And that RCD can serve both the Grid bypass as well as the Offgrid. I am sure that your thought was to protect the inverter, but that should only be done by an MCB at the input. The inverter itself is protected by all its electronic circuits and requires equipment grounding only. using an 100ma RCD might not change anything, but if you know that a wet panel is causing the issue, you might try to find out which panal is causing insulation resistance to drop and replace it...So, I would just remove the input RCD, as in some countries that would be against code anyways. Cheers.

@jmpcrx

Жыл бұрын

@@RolandW_DIYEnergyandMore thanks very much for your reply.. The inverter is in a shed and the supply to the inverter is taken from an rcd and breaker already in the shed, i did not install it just to protect the inverter/myself.. The panels are installed on a metal shed also, and ive read about capacitance tripping due to this? So possibly not actually down to a faulty panel?... The rcd is old, and ive just switched it out for a new one i had spare (still 30ma), and amazingly its not tripping at all now after spraying them with a hose for quite sometime (this normally trips the rcd ina few minutes). Possibly just an overly sensitive rcd? Or just as its old?.. But problem solved now, thank you.. 😃. 👍

@RolandW_DIYEnergyandMore

Жыл бұрын

@@jmpcrx great that the tripping stopped. But as I said, upsteam RCDs may sometimes cause a bit of problems if they mix up currents from Grid and PV systems. If you keep getting issues, get your bypass supply from the Grid shed supply directly via a double pole MCB only. Thanks for posting your experience.

@jmpcrx

Жыл бұрын

@@RolandW_DIYEnergyandMore ok, ill do that if it starts happening again... Thanks very much for your time, we may speak again lol 🙂👍👍👍

Hi Roland, I newly installed 5.5 kw off grid solar system. When I connect grid power to inverter, AC in RCD is immediately tripping. Otherwise inverter is working well in PV and battery. We have three phase current and single phase inverter. Only one phase is connected to inverter and inverter out is coupled to all three phases of the load. Please advise. Thank you

@RolandW_DIYEnergyandMore

Жыл бұрын

You have a N-PE bond after the RCD on AC in. if you didn't place a bond then the inverter is internally bonded. you can either remove the RCD at the AC-In and replace it by a 2 pole MCB or make a bond when inverter is in offgrid mode only as i am showing in my TT-system video. N-G(PE) bond can never be downstream of an RCD! I assume that at the moment the AC-In is coming from a circuit of your main panel which is protected by a 3 phase RCD. you need to get your AC-In from a point before that RCD. What is you inverter model?

@vijjeev9234

Жыл бұрын

Thank you very much. Greatly appreciate your help. AC in is coming directly from the grid, before going to the main panel. Our inverter model is SaKo Simon pro 5.5 kw. Three phase Grid is connected to 4 pole AC SPD and 4 pole MCB then 4 pole changeover from where it’s going to main distribution box and AC in to the inverter going through 2pole RCD.

@RolandW_DIYEnergyandMore

Жыл бұрын

@@vijjeev9234 ok. So yes, if your Sako inverter is providing a permanent internal N-PE bond (which you could check on AC out N and PE terminal if it is continuous in any mode), then an upstream RCD will always trip.

@vijjeev9234

Жыл бұрын

Thank you very much

@123qatar7

Жыл бұрын

​@Roland W I don't have utility I have only solar inveter, pv panels, When I installed RCD at out put of inverter its doesn't trip. Please advise ?😊

Really nice video, im currently writing an essay about the compare of the safety requirement (against electric shock) between the inverter with and without isolation. therefore ur video helps a lot, thank you very much. Additionally i still have a problem, so, are all the PV inverters, no matter isolated or non-isolated, they all need a RCD, and the only difference is, if there is a DC current injection, then use Type B, am I right?

@RolandW_DIYEnergyandMore

Жыл бұрын

Hi. In most developed countries there will usually be type a rcd used as a basic protective device against humans being injured through electrical shocks. That device is suitable in combination with isolated inverters. Only if the installed inverter is non-isolated transformer less type, the rcd used instead should be of type b. Additionally an installed ev charger can make the usage of a type b rcd required. So yes, you are right!

@vinnydu8554

Жыл бұрын

@@RolandW_DIYEnergyandMore Thank you for your reply! I have another two question. 1. When it comes to the limit value for RCD against electric shock, the regulation (IEC 621090-2) says that it's 30mA, i am always wondering whether this 30mA limit only for residual current or it's for the summary of both residual current and leakage current. (I've also read a technical information from manufacturer SMA that leakage can over 30mA, which is a little bit weird for me, because RCD doesn't know the current it measured is which current, if the summary is beyond 30mA, why would RCD not activate in this situation? 2. I've read the white paper from Schneider electric that u mentioned in this video, it says, even though some inverters have integrated RCD/RCMU inside of them, to preotect the Lines between the inverter and AC grid, there must be another external RCD put into use, i am wondering whether the trigger value of these two RCDs are the same？ Thank you again for your patience!

@RolandW_DIYEnergyandMore

Жыл бұрын

@@vinnydu8554 an rcd cannot distinguish between types of currents. It can only trip on the summery of missing currents it measures. The 30mA and 100mSec are typically worst case values. Normally 30mA rcds will disconnect the circuit starting around 20mA and won't go much over 25mA. There are special types which have short delays to prevent random activations. Every non-isolated inverter must have internal DC leakage detection. But that detection is very basic and is not based on human protection. It is purely designed to shut down the inverter itself. Those leakage currents thresholds could easily be in the hundreds of mA. That's why we need to use separate rcds inside the distribution.