Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Advice on GTIL Inverter
#21
I might be able to answer that for ya wolf...Yes and yes
Reply
#22
(08-20-2019, 10:51 PM)Doin it Wrote: Hey wolf, what would u recommend to monitor my home usage and solar production..I seen u use iotawatt... would u still recommend that..I’m not very tech savvy. I’d like something easy that I could monitor on my iPad. The iotawatt seems to plug into a 120 outlet but I see other devices that actually get wired to a 240v breaker as to see individual voltage difference between the phases.

I do use the IotaWatt. It has the same CTs that the GTIL uses to measure the powerflow from the grid to your house.
There are 14 seperate inputs that can be used so I have 2 obviously on L1 and L2 of my grid connection https://stuff.iotawatt.com/product-categ...nsformers/ and 2 right now coming off of my 2 GTIL on L1 and L2. https://stuff.iotawatt.com/product/current-transformer-50a-solid-core/

Plus I have 10 more of the 50a CTs to be installed on my main panel when I have the time to monitor individual circuits.
I do recommend it as its "relatively" easy to set up and use.

The IotaWatt has its own web interface and graphing capabilities so you can view it in a web browser on your iPad.
Also you can upload the data to several online databases and build your own dashboards.

If need be I can always team view or AnyDesk (My favorite) into your machine and help you out if you decide to go that route.

Wolf
If 18 X 650 = 2200+mAh then we have power! 
May all your Cells have an IR of 75mΩ or less Smile
Last count as of 8/7/2019
Total Number of Cells Recorded and processed                 6149
Total Cells required for PowIRwall                                   2856
Total Cells ≥2200mAh, ≥80%, ≥35mΩ, ≤75mΩ, ≥4.12V   2760
For Info Google Drive
Not your average Wolf       
            Cool
Reply
#23
So what about the voltage reference thing.. I see brands like sense that have 2 voltage reference wires going to a 240v double breaker to measure each phases voltage in the main panel. The iotawatts Voltage reference seems to only plug into a 120v outlet as to then only see the voltage of one phase and therefor assuming voltage in the other phase is the exact same?
My mains wires are just over 19mil so I guess I need the 200amp cts...
For the solar inverter cts will this one work? or is there a better ct for that? Both my inverters are connected to a subpanel with one wire going to main panel.. so I guess I need 2 cts installed on the wire coming out of subpanel, one for L1 and one for L2 and those 2 cts will monitor the output of both inverters as if they are one?
Reply
#24
(08-21-2019, 07:54 PM)Doin it Wrote: So what about the voltage reference thing.. I see brands like sense that have 2 voltage reference wires going to a 240v double breaker to measure each phases voltage in the main panel. The iotawatts Voltage reference seems to only plug into a 120v outlet as to then only see the voltage of one phase and therefor assuming voltage in the other phase is the exact same?
My mains wires are just over 19mil so I guess I need the 200amp cts...
For the solar inverter cts I didn’t see the 9mil ct u suggested but will this one work? or is there a better ct for that? Both my inverters are connected to a subpanel with one output wire going to main panel..so no more than 20amps will be seen on that wire going to main panel so is the 50amp one in the pic good or should I try harder to find the one u suggested in the link for better accuracy?
The V reference thing is a calibrated transformer that plugs into 1 of the inputs. I guess for them it was not that important to know the 120 V of both sides.

I am also assuming that the V of L1 and L2 is pretty close as I have measured it and they both are spot on compared to each other. +1 for my power company. As long as they don't change the transformer I don't foresee too much of a change on that. But who knows. If it is that important to you than the IotaWatt won't work.
Otherwise let's continue.
Their CT selection is pretty large so you can choose from their recommended list.
 
Yea that one will work but you sure you didn't find this one?

https://stuff.iotawatt.com/product/curre...olid-core/

Wolf
If 18 X 650 = 2200+mAh then we have power! 
May all your Cells have an IR of 75mΩ or less Smile
Last count as of 8/7/2019
Total Number of Cells Recorded and processed                 6149
Total Cells required for PowIRwall                                   2856
Total Cells ≥2200mAh, ≥80%, ≥35mΩ, ≤75mΩ, ≥4.12V   2760
For Info Google Drive
Not your average Wolf       
            Cool
Reply
#25
I just changed a lot of what I said above wolf...sorry

Yeah I ended up finding that one...but is the one in the pic the same but just split, so I wouldn’t have to disconnect the wires? As for the voltage reference, well idk if it should be important, I was kinda asking if I should worry bout that. If let’s say actual voltage on one leg was 1 volt different than other leg then couldn’t it read wrong,,,as in that 1 volt multiplied by however many amps that leg is using

Here’s my cart..I can change the last 2 cts if u think I should. Won’t be that big of a deal to disconnect the wires and run them thru the non split cts if it would be more accurate
Reply
#26
Wolf found this info on voltage reference...what ya think...mighta been part of the reason your unbalanced panel with your graphs showing backfeed...

The graphs basically show that when there is more power being drawn on one leg than the other, that the voltages can vary. So if a main panels legs are not well balanced and the total home power usage is trying to be monitored using a single voltage reference from one leg, then the measurements-graphs will be incorrect. In the graph it shows as much as 3volts different and that would be times the amps being drawn at the time.
Reply
#27
(08-21-2019, 08:43 PM)Doin it Wrote: Here’s my cart..I can change the last 2 cts if u think I should. Won’t be that big of a deal to disconnect the wires and run them thru the non split cts if it would be more accurate

I'll get back to you on all of that but looks good so far. Split or no split CTs  your choice I have the solid ones just because I can disconnect the wires and slip them over it and they take up less space. Don't know about accuracy difference. I know Sean posted a sheet showing the possible error count of some CTs. I think it was in the +-3% range. 
(08-21-2019, 11:36 PM)Doin it Wrote: Wolf found this info on voltage reference...what ya think...mighta been part of the reason your unbalanced panel with your graphs showing backfeed...

The graphs basically show that when there is more power being drawn on one leg than the other, that the voltages can vary. So if a main panels legs are not well balanced and the total home power usage is trying to be monitored using a single voltage reference from one leg, then the measurements-graphs will be incorrect. In the graph it shows as much as 3volts different and that would be times the amps being drawn at the time.

While the voltage difference may be true I highly doubt that a 3 Volt difference between legs would cause a 150 Watt backfeed to show up on the graph W=V X A  My house idles at ~200 Watts per leg so lets say 120 X 2A =240 Watts lets say we have 1 leg at 115V X 2A =230Watts and the other at 125V X 2A = 250 Watts that is a 20 Watt difference. take the CTs inaccuracies and lets push them to 5%
against our favor 230 Watts - 5% = 11.5 Watts lets say 12 Watts  thats  218 Watts.  250 Watts + 5% +12.5 Watts lets say 13 Watts thats 263 Watts.  263-218=45 thats using all of the calculations against us. Also I was feeding single phase 240 with the inverter so the Voltage should have been pretty close between Li and L2.
Now I do understand that 1 leg was off balance but even so I do not believe a 3 Volt difference would cause the graph to show I was back feeding as much as I was even with the deck of numbers stacked against me.


Wolf
If 18 X 650 = 2200+mAh then we have power! 
May all your Cells have an IR of 75mΩ or less Smile
Last count as of 8/7/2019
Total Number of Cells Recorded and processed                 6149
Total Cells required for PowIRwall                                   2856
Total Cells ≥2200mAh, ≥80%, ≥35mΩ, ≤75mΩ, ≥4.12V   2760
For Info Google Drive
Not your average Wolf       
            Cool
Reply
#28
Agreed wolf,,,I said that it could have been “part of the reason”. Although at the spots on the graphs where voltages are the most different the legs were more severely unbalanced (a lot more amperage on one leg than the other) which is what was causing the voltages to vary up to 3%. So there is probably a higher amperage number that could be put in that math, which could make that watt total rise a bit.
Like I said tho only part of the backfeed reading mighta been due to that...the rest of the backfeed reading was from your panel being so unbalanced using a 240v inverter..so then dare I say instead of a 150w backfeed maybe 30w of that (at the highly unbalanced times) was actually not backfeed but instead improper voltage reference reading due to only reading voltage of one phase..
To avoid any of this incorrect reading (albeit a small amount) I looked into neurio home monitor (voltage reference from each leg) but their customer service is garbage from what I read..so what other option do I have (besides sense) that will read voltage from both phases on the leg

Maybe I’m wrong but I feel like the math should be a possible 3% voltage difference difference (x) a possible 30amp amperage draw on the leg with more loads (=) roughly 90watts max...again might not be looking at that right and I suppose the 30amps might not be accurate but could be at any time....90w for 10 hrs isn’t even a kw so probably doesn’t add up to much...also tho depending if the voltage reference was on the leg with more or less load amps (and or more or less volts) at the time of the load unbalance could make a difference as to whether or not the usage monitor would see more or less usuage than what was actually occurring on the leg that the monitor isn’t voltage referencing...lol longest sentence that isn’t really a sentence I ever wrote
Reply
#29
(08-22-2019, 01:24 AM)Doin it Wrote: Agreed wolf,,,I said that it could have been “part of the reason”. Although at the spots on the graphs where voltages are the most different the legs were more severely unbalanced (a lot more amperage on one leg than the other) which is what was causing the voltages to vary up to 3%. So there is probably a higher amperage number that could be put in that math, which could make that watt total rise a bit.
Like I said tho only part of the backfeed reading mighta been due to that...the rest of the backfeed reading was from your panel being so unbalanced using a 240v inverter..so then dare I say instead of a 150w backfeed maybe 30w of that (at the highly unbalanced times) was actually not backfeed but instead improper voltage reference reading due to only reading voltage of one phase..
To avoid any of this incorrect reading (albeit a small amount) I looked into neurio home monitor (voltage reference from each leg) but their customer service is garbage from what I read..so what other option do I have (besides sense) that will read voltage from both phases on the leg

Maybe I’m wrong but I feel like the math should be a possible 3% voltage difference difference (x) a possible 30amp amperage draw on the leg with more loads (=) roughly 90watts max...again might not be looking at that right and I suppose the 30amps might not be accurate but could be at any time....90w for 10 hrs isn’t even a kw so probably doesn’t add up to much...also tho depending if the voltage reference was on the leg with more or less load amps (and or more or less volts) at the time of the load imbalance could make a difference as to whether or not the usage monitor would see more or less usuage than what was actually occurring on the leg that the monitor isn’t voltage referencing...lol longest sentence that isn’t really a sentence I ever wrote

LOL I am confused by your math 30A draw on 240 is 7200 Watts  on 120 its 3600 Watts  The highest draw I have ever experienced on my system is ~2000 Watts and that is on L1.
Here is my 90 day chart. You can definitely see the start of AC season.


I do agree though 90 Watts would not be a lot of backfeed but it all depends if the power company sees that and questions it with their "smart meter".
Comes to investigate and either replaces it or questions on what is happening here. Angel

Wolf
If 18 X 650 = 2200+mAh then we have power! 
May all your Cells have an IR of 75mΩ or less Smile
Last count as of 8/7/2019
Total Number of Cells Recorded and processed                 6149
Total Cells required for PowIRwall                                   2856
Total Cells ≥2200mAh, ≥80%, ≥35mΩ, ≤75mΩ, ≥4.12V   2760
For Info Google Drive
Not your average Wolf       
            Cool
Reply
#30
Well for instance microwave is 1000w which is 120 that could be an imbalance on one leg but that’s only for a few seconds-minutes...we have a turbo cooker that uses 1800w that is 120v....30 amps tho was a bit ambitious. Hair dryer etc. Or just a few low wattage 120v things all on one leg...I see a lot more wattage on my legs of the main panel...I seen over 6000w being used at 240v, some of the things were 120 I’m sure.
As for the electric company..well my meter used to say error (backfeed) from time to time when I had unbalanced loads in the panel happening, like microwave etc. The meter also said error(backfeed) when I just had one inverter wired 240v, seemed to me that the cts-cable from the fella on eBay was letting the single inverter backfeed when the inverter was covering all of the loads...after I installed the second inverter (paralleling another connector to the sense cable) it allows the grid to supply more power therefor no longer backfeeding when the inverters are covering all of the loads. But I still see error when I run the microwave.
Reply


Who read this thread?
31 User(s) read this thread:
daromer (08-19-2019, 05:58 AM), emuland-metroman (08-19-2019, 07:30 PM), sl1me (08-28-2019, 04:26 AM), Wolf (08-24-2019, 01:18 AM), Solardad (09-07-2019, 07:46 PM), ajw22 (09-04-2019, 02:30 AM), RikH (08-19-2019, 07:44 PM), OffGridInTheCity (08-20-2019, 04:55 AM), Doin it (08-30-2019, 09:26 PM), gpearce52 (08-19-2019, 09:50 PM), Marrcin (08-21-2019, 07:21 PM), 3xtr3m3 (08-20-2019, 06:46 AM), suntan901 (08-27-2019, 03:29 PM), SanDiegoMaxim (09-03-2019, 01:19 AM), chuckp (08-25-2019, 04:16 PM), Riplash (08-24-2019, 10:44 PM), avm131 (08-21-2019, 06:46 PM), Sean (08-24-2019, 08:37 AM), Majorphill (08-23-2019, 05:00 AM), Korishan (08-24-2019, 03:00 AM), jdeadman (08-23-2019, 07:03 PM), wim (08-22-2019, 06:02 AM), watts-on (08-24-2019, 10:32 AM), Geek (08-19-2019, 04:41 AM), Ivo Staelens (08-23-2019, 05:20 PM), ad8mustanggt (08-28-2019, 08:32 PM), cnous3 (08-26-2019, 02:32 PM), BaronVonChickenPants (08-20-2019, 03:02 AM), EnergyDoc (09-05-2019, 06:01 AM), completelycharged (08-24-2019, 03:34 PM), nettermann90 (08-22-2019, 06:57 AM)

Forum Jump:


Users browsing this thread: 3 Guest(s)