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  • #16
    Originally posted by Sunking View Post

    JPM Morningstar is just one of hundreds of manufactures that get Bonding and Grounding wrong. The one thing they have in common is the note after Step 4 you can go read. Something to the extent of:: Consult Local Electrical Codes. Not unique to solar but something in common you see with 12 volt topology. Steve will chuckle when he sees that Ham Radio equipment is smeared with all sorts of crazy ground instructions. It is what happens when you let Lawyers write electrical specifications. Check with Local Electrical Codes is CYA.

    There are some members if they look agree something is not right. You do not bond a Neutral twice and I bet you know it too. Lots depend on how it is switched in and used. Another thing that might interest you is the use of a 100 Amp fuse on a 300 watt Inverter. 100-Amp Fuse is a great math for a 1000 to 1200 watt Inverter @ 12 volts. A 300 Watt Inverter only needs a 30-Amp Circuit. A fault inside the Inverter may or may not draw more than 100 amps to operate the breaker. It could just sit there and cook until it burned the internal wiring to act as a fuse.

    This is not to say the product is not a quality product. Morningstar makes a reputable product, but their Instructions need some work.
    Understood and not disagreeing. I'm aware of the basics of electricity, electrical design and accepted practice, and the reasons behind why things are done as they are, but what we're talking about here is outside of areas where I claimed engineering competence before I retired my license so, I defer to your lead in these matters rather than mouth off and leave no doubts as to my ignorance and hubris.

    But at this time, I don't need a whole lot of technical acumen to see that the OP is looking at instructions that you're saying are at least partially incorrect and if I read what you're writing correctly, may well be troublesome if not dangerous. So, what's he to do ? Seems to me he's between a rock and a hard place: Take your advice and possibly do something counter to what's written by Morningstar, and in so doing perhaps void any warranty or chance of a successful insurance claim or lawsuit, or follow written instructions and, if you are correct (which I'm not disputing) possibly cause property damage or personal injury, or both ?

    Seems to me too that until more information is conveyed between all parties and all the facts and particulars of the application are clear(er), it may be best for the OP to not connect the Morningstar product if only to cover his butt.

    That's why I suggested he contact Morningstar and copy them with this entire thread and ask for their version of reality.

    Does the NEC or their minions have any definitive wisdom to offer on the matters at hand ?
    How about Mike Holt, et al. ?

    That there are hundreds of manufactures that get Bonding and Grounding wrong seems strange. Might it have something to do with no two applications being quite the same ?

    Still got your 6.

    Respectfully,
    Last edited by J.P.M.; 06-02-2020, 12:09 PM.

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    • #17
      I can’t test the inverter because UPS has it but I will when it arrives. I think what you are saying is that the RIB 25401D shouldn’t be used. Maybe there is a transfer switch that I can use here instead of the relay. Plug-n-play will not work. I would have to hire someone to plug it in. This system has to switch ac sources when I am not home- that’s the whole problem- I can’t go anywhere. It would be great if I was home all the time but I feel like a dairy farmer tied to the cows. This system would not be put on line unless I was not going to be home and it would, in fact be plug-n-play 95% of the time because I’m home most of the time. What do you think about the transfer switch idea? I like relays- they seem to work well- I have 7 of them here on the system and the first one I put in about 20 years ago but I understand they have their limitations but I have to have a device to do work when I’m not here.

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      • #18
        Originally posted by jeffy104 View Post
        I think what you are saying is that the RIB 25401D shouldn’t be used. Maybe there is a transfer switch that I can use here instead of the relay.
        A Transfer Switch is a relay, just do not know anything about your relay. What is bothering me what you want is a UPS. You should have just bought one rather than try to make one.

        MSEE, PE

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        • #19
          Yeah I tried to find a UPS- I looked for quite a while but there’s nothing out there that will do the job without spending thousands. Thousands that I don’t have. The relay I have is top of the line. I forget how many cycles of operation it’s rated for but it’s a lot. Solid state and rated for 10 amps 120 vac. It’s an industry standard relay. I’m still waiting on the inverter but it should be here soon and I will check it as you have said. I’ll let you know what the results are. If I have time today I am going to test the relay without the inverter- I’ll use the grid for both sources of ac and for a load I’ll use a 100 watt bulb. Like you say, a mistake will be bad news. Better to see how it works in the shop. Again, thanks for your input.

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          • #20
            Originally posted by jeffy104 View Post
            I can’t test the inverter because UPS has it but I will when it arrives. I think what you are saying is that the RIB 25401D shouldn’t be used. Maybe there is a transfer switch that I can use here instead of the relay. Plug-n-play will not work. I would have to hire someone to plug it in. This system has to switch ac sources when I am not home- that’s the whole problem- I can’t go anywhere. It would be great if I was home all the time but I feel like a dairy farmer tied to the cows. This system would not be put on line unless I was not going to be home and it would, in fact be plug-n-play 95% of the time because I’m home most of the time. What do you think about the transfer switch idea? I like relays- they seem to work well- I have 7 of them here on the system and the first one I put in about 20 years ago but I understand they have their limitations but I have to have a device to do work when I’m not here.
            On the issue of not at home, and for no more than FWIW because I'm ignorant of your roof access situation, when I travel, if I'm gone for any length of time, I cover my water heater's panels in case the power might die. That takes me 2 trips to the roof and about 2 minutes total time or less.

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            • #21
              I almost built a set of stairs to the roof of my shop last year- that’s where the panels are, to do the same thing. I still may but not until I have exhausted all other options. I probably have the most efficient and advanced heating system in the Adirondacks. You would think that this would be easy compared to the installation of the system, not to mention the cost but I’m finding out there’s a bit more to it. All the same, I've set up 100 kw onans in the Alaskan bush, built and wired two homes, fought off pirates down near Haiti, had to kill grizzlys to protect my family, came home late one time only to find out my wife was mortgaging the house for helicopter time to rescue me after the coast guard told her they were looking for a body, and the list goes on. But you get the idea- I’m going to have something in place somehow so I’m not tied to a heating system that cost as much as my home and 70 acres. I’m the boss and that darn heating system is going to know it for sure. LOL

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              • #22
                Jeff is the motor hard wired or Plug-N-Cord. We can make this real easy, reliable, and inexpensive by making a UPS.
                MSEE, PE

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                • #23
                  It has a plug in cord which powers a small computer and some sensors and the computer runs the pump.

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                  • #24
                    Beware the sold state relay (SSR) They are extremely sensitive to Kickback voltages, even with DC lines. And you must slam them on HARD and slam them OFF. never a "gentle transition", that's when they start overheating and fry in a second.
                    So read up on "Snubbing Circuits" for SSR's
                    Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
                    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
                    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

                    solar: http://tinyurl.com/LMR-Solar
                    gen: http://tinyurl.com/LMR-Lister

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                    • #25
                      I looked into that. I mistakenly call the relay solid state. I should have said “enclosed”. I looked at the relay board and assumed solid state but the click sound it makes should have told me it was mechanical. Some relays I have here are exposed and clunky looking but they only turn things on and off and aren’t involved in switching ac sources. The funny thing is that there are other people that have the same problem I have but it’s hard to track down any info. I asked the installer about power failures when he was here and he said the biggest problem anyone had was the “main” computer (on the boiler) switching from English to German. He also said that as far as the solar part of the system goes, some people use a battery and an inverter. I’m sure I was correct in thinking he was talking about a backup which required you to be home to use it. And that’s where this can of worms comes from. I appreciate all the input I’m getting here- all you guys are a great resource for “secret” information. Thanks.

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                      • #26
                        Originally posted by jeffy104 View Post
                        It has a plug in cord which powers a small computer and some sensors and the computer runs the pump.
                        Oh gosh this is easy then. You may not like the idea at first, but is how it is done. Basically you are going to make a Dual Conversion UPS, or I like to call them Poor Mans UPS. Sounds complicated but Stupid Simple.

                        AC Powered Battery Charger > Battery > Inverter.

                        That is all there is to it. Only real trick is sizing the Battery Charger and Battery. The Charger is sized to charge the battery in 12 to 16 hours, plus the load. Where you start is by first determining the Run Time. By that I mean how many hours you want it to run before the battery is exhausted. To do that you need to know how many watts the load is times the hours you want it to run. So say you device uses 100 watts and you want to run 10 hours. 100 watts x 10 hours = 1000 watt hours. This leads us to determining both the Battery Capacity and Charger Size

                        Since this is a UPS we can get away discharging down to 80% DOD. It will be a rare event it is ever running on batteries. 99% of the time on commercial power. So to account for 80% DOD and 90% efficiency the battery capacity Watt Hours x 1.4 / Battery Voltage. So 1000 Watt Hours x 1.4 / 12 volts = 117 Amp Hours. So would be looking for a 12 volt 120 to 150 AH battery in this example.

                        Charger size in this example is stupid simple to calculate C/10 where C = Battery Amp Hour Capacity. So say you buy a 120 AH battery means you need a 12 Amp Charger. There is some wiggle room so you are looking for a 10 to 15 amps Float Charger.

                        It is a much better option, more reliable, cost less, and battery will last much longer than doing this with Solar. To do this with Solar would require a battery 4 to 5 times larger, requiring a large solar panel array and a large expensive charge controller.

                        He is an idea on cost. To build yourself a UPS with a Charger and Battery. less than $300.

                        Want Solar? To start you are looking at a 800 to 1000 Watt Panel System so there goes $2000 down the drain, another $600 for the Charge Controller, plus a monster sized $500 battery Easily $2500 to $3000 or roughly 10 times more upfront initial cost, and since you will cycle your batteries daily means a lot more frequent battery replacement of a battery 4 to 5 times larger.

                        So you might want to rethink this and build you a UPS. Will get you where you want for a whole lot less money and simple to use. Just unplug your gizmo, plug the charger in it place, plug your Gizmo in the Inverter and call it done. .
                        MSEE, PE

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                        • #27
                          Yes. That’s exactly what I’m making here. Exactly. Batteries maintained by a charger which I will run only when needed- which will be hardly ever. An inverter ($277) to make the ac. And then the heart of the system- the relay. Without the relay all this work and expense is worthless. It has to do the work of switching ac sources all by itself. The inverter has dip switches on it and by setting them a certain way, the inverter can be programmed to have a standby mode. When the inverter senses a load of 8 watts or greater, it supplies ac output. Unfortunately, I’m pretty sure this won’t work for the computer that runs my pump but the flip side is that this pump will be on the grid 99,999999999% of the time. It just won’t be used much at all. I can also set voltage thresholds with the dip switches. I tested the relay today (no inverter yet) and it works perfect. It puts the voltage where I want it when I want it there and there’s no back feed from the grid to the inverter or from the inverter to the grid. I just used the grid in place of the inverter because the inverter is still in transit from amazon. I know I’m using the relay as a transfer switch and it works exactly the way it needs to but I’m waiting to hear that under no circumstances should this be done. In the mean time when I have contacts that are either N/O or N/C (normally open- normally closed) voltage can only flow where there is a circuit and is blocked where there is none. I’ll test it to see how long the system supplies useable power to the pump and adjust battery capacity. I also have to find out what the minimum voltage is for the computer/pump. There is also power consumed when the inverter is on but in a no-load state and the amount of power consumed is made up for by the
                          charger. Dip switches control when the inverter shuts down due to low battery. I’m still waiting on the inverter so I can test resistance. I have a friend who has the exact same system and he doesn’t even have stand-by power. His system blew last year when the power failed and the sun was out. When the power fails here, and the sun is out, I start my generator. I told him I could install the same thing at his house once I figure this out but have since changed my mind and can only offer to show his HVAC man what I have done here and under no circumstances will put this in his house. In the mean time I can only suggest he get a generator. Some day I’ll have a auto stand-by generator and all this will be moot. LOL Thanks again for your reply.

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                          • #28
                            Sunkings method, running the pump 100% of the time off the inverter, needs no relay. But the inverter is now 100% in charge. If it fails, so does the pump.

                            But you really need to wire the relay properly if you use it to alternate between Grid and Inverter. And does that same relay also engage the 12V for the inverter ? And be sure to try it first.

                            If the grid fails, and the relay switches over, the inverter now has a load and is being powered up from a cold start. Some inverters do that fine, some won't
                            Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
                            || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
                            || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

                            solar: http://tinyurl.com/LMR-Solar
                            gen: http://tinyurl.com/LMR-Lister

                            Comment


                            • #29
                              Yes, the inverter will run the pump but only if I’m not home and only if the power is out. If I leave, the inverter will be powered up but not powering anything but itself. The output of the inverter is wired to the relay on a normally closed contact so when the grid is on, this contact is open and the output of the inverter goes nowhere. When the relay loses the 24vac from the grid powering the coil, the inverter is connected to the the same ac duplex receptacle that the grid is connected to, but the grid has now been disconnected from the outlet so there can be no backfeed to the panel. After triple checking and checking the drawing again, I assembled the circuits in the shop and it proved out with the DMM. This receptacle will not be used unless I’m not home, and it will be on it’s own breaker which will be turned off 99.99999% of the time. It’s not needed when I’m home. I hadn’t planned on a switch between the battery and the inverter. The inverter gets 12v to it’s own switch 100% of the time but it’s turned off 99.99999% of the time. There is a certain order to the things which are done to bring the inverter into play with the special relay-controlled receptacle and I’ll have to leave written instructions for myself so I don’t screw it up and fry something. There will be a switch between the transformer and the coil on the relay because the relay doesn’t need to be running 99.99999% of the time- just when I leave. I do need to find out why the inverter people want a 100 amp fuse on a 300w unit. Not thinking I followed their instructions and bought 100 amp fuses for the holder. THAT does not make any sense to me now that I’ve had time to think about it. Still waiting for the inverter to arrive for Sunking’s resistance test. I am thinking I may just bite the bullet and run a new ground rod for the inverter but I just get the feeling that somehow it should be on the same ground rod as the panel. I’m still wondering about that. Thanks again for following along.

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                              • #30
                                So now I’m searching for the fuse holder for the output ac line on the inverter. Can anyone point me in the right direction to a fuse holder that I can connect 12 AWG wire to? It’s only a 3 amp fuse but the instructions say to use #12 wire so I was hoping to find one that would work.

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