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Recent Posts
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Renewable Energy Q&A / Re: Max winding temp
« Last post by rossw on June 29, 2022, 07:31:31 pm »Spray drift
Quote
nowhere is safe from chemical sprays.
It can be a real problem.
I'm on a modest 22 acres. We moved here 20 years back and one of our conscious decisions has been to use mechanical and biological weed control measures - we cut and dig out blackberry roots and all, we encourage the Chrysolina beetle to control St John’s wort, slash and leave Pattersons Curse, and over-graze some areas where the sheep and alpacas can control nuisance weeds.
The amount of bird life here has increased by an order of magnitude both in diversity and quantity, we have heaps of frogs and lizards and other critters that were virtually absent when we got here, and lots of sensitive native flora like various insectivorous plants, kangaroo grasses etc are re-establishing.
We have neighbours who still choose to spray poisons around, and the council, but all are well aware of our concerns and "organic" status and most do actually make a decent effort to ensure we get no spray drift.
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Renewable Energy Q&A / Re: Max winding temp
« Last post by Pete on June 29, 2022, 06:53:22 pm »Spray drift eh. I was talking to a beekeeper years back and he was totally confused because he lost something like 100 hives and could not work out what caused it.
I asked him where they were and if there were any tree plantations nearby. He told me and I knew his problem straight away.
Spray drift from the plantations was it.
The plantations were sprayed regularly with a chemical called Alphacypermethrin. It is used to kill the eucalypt beetles that eat the trees.
Well as we know if it kills one insect it kills them all and the bees were not far from the plantations.
I had a friend who had his whole crop of Flowers that he had been selectively breeding for 20 years wiped out by the farmer next door spraying 2-4-D.
The farmer denied it but also happens to run a dairy and has a well frequented cheese factory. Unfortunately for my friend and his 20 year Hellebore program the farmer was from a rich family with political connections and nothing was done about the spray drift.
Our state claims to be a Clean Green state, but nowhere is safe from chemical sprays.
Glad the documents are helping and hope the problem with the motor stays fixed
Pete
I asked him where they were and if there were any tree plantations nearby. He told me and I knew his problem straight away.
Spray drift from the plantations was it.
The plantations were sprayed regularly with a chemical called Alphacypermethrin. It is used to kill the eucalypt beetles that eat the trees.
Well as we know if it kills one insect it kills them all and the bees were not far from the plantations.
I had a friend who had his whole crop of Flowers that he had been selectively breeding for 20 years wiped out by the farmer next door spraying 2-4-D.
The farmer denied it but also happens to run a dairy and has a well frequented cheese factory. Unfortunately for my friend and his 20 year Hellebore program the farmer was from a rich family with political connections and nothing was done about the spray drift.
Our state claims to be a Clean Green state, but nowhere is safe from chemical sprays.
Glad the documents are helping and hope the problem with the motor stays fixed
Pete
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Renewable Energy Q&A / Re: Max winding temp
« Last post by rossw on June 26, 2022, 03:41:49 am »Crops are doin great
Hah, you're lucky.
Where I am, the *WEEDS* are doin' great. Other things ok, but weeds are going bonkers!
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Product Reviews / Re: Mini Split
« Last post by lighthunter on June 25, 2022, 09:57:30 pm »So, weve added two more of these units to the house. Now the solar panels can heat or cool the house and the garage for very low cost and the solar takes care of most if not all of the day use. The two 9ks were installed in march i think. The calculated usage to cool the house in 90F weather is about 315 kwh per month. Thats under $30usd/mo at our rates, much less with solar. With 7kw of solar one 3kw array doesnt even turn on when its sunny. These last two models are hyperheats wheras the first one was just the plain version. If anyone is confused about all the seers, hspfs, eers, 9k, 12k etc, there are so many things to consider, just go to a website called NEEP. Its like AHRI but way better. These guys do tests and record data for you to see. The COP heating performance at 5° tells the story. So any machine that can get close to 2.0 COP at 5° is very efficient at heating. The hyperheat version isnt necessarily more efficient, but it can hold the btu heat capacity output at 5° wheras the nonhyper models decline to 50% btu output at that temp. Colder than 5°F they will continue to decline output but hypers will just produce more heat at that temp and also use more electricnpower to do it, so long as COP stays above 1.5 or so its still a win. Ive been exposed to several brands now and ive not seen or heard of anyone that had a problem. Not sayin it couldnt happen but seems like a mature product, they have it figured out how to build em. Im not the kind to spend a lot on things. They dont give the things away but they werent too bad either if you put them in yourself. No higher cost than any other heating system and this does both. Its just such a great compliment to solar.
We are very happy so far. Cleaning cotton fuzz from radiators with garden hose has been only maint so far. The two 9ks are usually running 1.3 to 2.5 amps 240AC during the 90 degree weather.
We are very happy so far. Cleaning cotton fuzz from radiators with garden hose has been only maint so far. The two 9ks are usually running 1.3 to 2.5 amps 240AC during the 90 degree weather.
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Renewable Energy Q&A / Re: Max winding temp
« Last post by lighthunter on June 25, 2022, 07:05:10 pm »Hey Pete, that Heco document is wonderful. We still have no email service where i work so have not gotten info on winding class yet. Because the alarm temp control i put in only has a max setting of like 209F thats what i set it to. It runs at about 185°F so am real happy with it now. The motor current at 60 hz 3600ish rpm is 200A, nameplate is 166A, thats a bit concerning but it doesnt have to run there very often.
Again that heco document is better than any i had found on the subject.
The heat here is crazy lately like near 100 with high humidity but it rained last night so its been nice today. Crops are doin great. Its hard to make it through June without your garden being wiped out by drifting farm chemicals but this year is a bit better, lost some peppers but the rest pulled through. Even the apple trees have leaves still looking like a leaf rather than the gnarled curled shape they usually get from sprays. Ha for years i thought it was cedar apple rust until i finally caught on to it. Hope everyone is doing well!
Again that heco document is better than any i had found on the subject.
The heat here is crazy lately like near 100 with high humidity but it rained last night so its been nice today. Crops are doin great. Its hard to make it through June without your garden being wiped out by drifting farm chemicals but this year is a bit better, lost some peppers but the rest pulled through. Even the apple trees have leaves still looking like a leaf rather than the gnarled curled shape they usually get from sprays. Ha for years i thought it was cedar apple rust until i finally caught on to it. Hope everyone is doing well!
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Renewable Energy Q&A / Re: Max winding temp
« Last post by Pete on June 15, 2022, 05:42:10 pm »Hi Lh, well that was a novel solution.
Here is a link to a page about winding insulation temperature ratings.
A H class winding will have White Nomex slot insulation. The rest of the insulation will be mica or fibreglass for phase insulation and leads.
Pity that Siemens pack the motors windings in too tight and fit too big a motor into a small frame.
Gone are the days where open frame motors could be run at double their ratings. Nowadays the ratings are absolute max.
I hope you are well and that the workaround stays working.
I guess some sort of air dryer like spray painting sets have could work but sounds like you are putting a lot of air into the motor.
Cheers
pete
https://www.hecoinc.com/blog/electric-motor-insulation-class-what-is-it
Here is a link to a page about winding insulation temperature ratings.
A H class winding will have White Nomex slot insulation. The rest of the insulation will be mica or fibreglass for phase insulation and leads.
Pity that Siemens pack the motors windings in too tight and fit too big a motor into a small frame.
Gone are the days where open frame motors could be run at double their ratings. Nowadays the ratings are absolute max.
I hope you are well and that the workaround stays working.
I guess some sort of air dryer like spray painting sets have could work but sounds like you are putting a lot of air into the motor.
Cheers
pete
https://www.hecoinc.com/blog/electric-motor-insulation-class-what-is-it
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Renewable Energy Q&A / Re: Max winding temp
« Last post by lighthunter on June 14, 2022, 06:26:59 pm »Update:
Thanks again Pete for all the ideas and thoughts on this one. All attempts to adjust the volt/amp curve via vfd programming failed as the OEM disallows it. Weve yet to get any real support from those people.
The compressor has been running fine for a while now. I drilled a hole near the bottom of the end frame and put compressed air to it so it blows cool air through the cage out the cover of electrical box. A co-worker drilled the fitting a bit larger as the cooling requirement was higher than i had anticipated. It takes around a 6hp efficiency hit just to cool it but it works. Runs about 175F now. Whats difficult for me is knowing exactly whats ok? A different unit had oiltemp that reached 221F today. Pressure washed cotton fuzz from radiator and now at 196 where thermostat regulates it. Maybe its fine for winding temp to be 250F no one i know will go there and articles written about it tiptoe around the subject. Oddly most manufacturers do not put temp sensors in windings yet a common house fan includes this as a safety device. A thermal cutoff or tco. As i write this im reminded of an event years ago... 1998... how time has gone... when a laser roots blower also siemens motor, failed due to a temp sensor in winding. I jumpered and machine ran, i ordered a temp switch in a T0220 package and inserted/epoxyed into winding at end of motor seems like i started at 110C and kept having to order higher ones till i got one that didnt trip under normal circumstances. Seems like the number was 115 or 120C when i finished and that one ran for years that way. So by that info i can set this at 250F and reduce the orfice size to maybe 4HP of cooling. Of course an air booster in reverse trading pressure to volume would reduce the flow requirement again. Anyone else agree i can increase thermal trip point to 250F or 120C?
I kinda feel stupid i forgot the eqperience i learned back then about winding temp.
Perhaps i better ask the elder gentleman what class wind wire he used for this one.
Its not an ideal solution but it is a solution and it does run welll now. Anyone have an idea on a moisture sensor for air line. I will need it to fault on humidity as moisture will kill windings too. So far our dryer is flawless but theres no feedback to stop anything if it doesnt remove all moisture.
Hope everyone is doing well, i havent had much time to post as garden, work and other odd jobs have been over the top lately.
Thanks again Pete for all the ideas and thoughts on this one. All attempts to adjust the volt/amp curve via vfd programming failed as the OEM disallows it. Weve yet to get any real support from those people.
The compressor has been running fine for a while now. I drilled a hole near the bottom of the end frame and put compressed air to it so it blows cool air through the cage out the cover of electrical box. A co-worker drilled the fitting a bit larger as the cooling requirement was higher than i had anticipated. It takes around a 6hp efficiency hit just to cool it but it works. Runs about 175F now. Whats difficult for me is knowing exactly whats ok? A different unit had oiltemp that reached 221F today. Pressure washed cotton fuzz from radiator and now at 196 where thermostat regulates it. Maybe its fine for winding temp to be 250F no one i know will go there and articles written about it tiptoe around the subject. Oddly most manufacturers do not put temp sensors in windings yet a common house fan includes this as a safety device. A thermal cutoff or tco. As i write this im reminded of an event years ago... 1998... how time has gone... when a laser roots blower also siemens motor, failed due to a temp sensor in winding. I jumpered and machine ran, i ordered a temp switch in a T0220 package and inserted/epoxyed into winding at end of motor seems like i started at 110C and kept having to order higher ones till i got one that didnt trip under normal circumstances. Seems like the number was 115 or 120C when i finished and that one ran for years that way. So by that info i can set this at 250F and reduce the orfice size to maybe 4HP of cooling. Of course an air booster in reverse trading pressure to volume would reduce the flow requirement again. Anyone else agree i can increase thermal trip point to 250F or 120C?
I kinda feel stupid i forgot the eqperience i learned back then about winding temp.
Perhaps i better ask the elder gentleman what class wind wire he used for this one.
Its not an ideal solution but it is a solution and it does run welll now. Anyone have an idea on a moisture sensor for air line. I will need it to fault on humidity as moisture will kill windings too. So far our dryer is flawless but theres no feedback to stop anything if it doesnt remove all moisture.
Hope everyone is doing well, i havent had much time to post as garden, work and other odd jobs have been over the top lately.
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Users Projects / Re: y Philippines Retirement Solar Off Grid System
« Last post by solarnewbee on June 04, 2022, 02:28:40 am »I meant to say put one battery on top of the other. They are sealed so no checking levels.
On the other subject, I have a short across the battery connections on this inverter board. Thought it might be the caps or the mosfet over by the egs board but not so. I reckon I was sold at least 1 bad hy4008. Jumped the gun and didn’t get out the tester before putting them in. I am officially trashing this board because I would have to desolder every single fet. No thanks.
Thanks for your help tho. Adios!
On the other subject, I have a short across the battery connections on this inverter board. Thought it might be the caps or the mosfet over by the egs board but not so. I reckon I was sold at least 1 bad hy4008. Jumped the gun and didn’t get out the tester before putting them in. I am officially trashing this board because I would have to desolder every single fet. No thanks.
Thanks for your help tho. Adios!
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Users Projects / Re: y Philippines Retirement Solar Off Grid System
« Last post by Pete on June 03, 2022, 03:12:21 am »Hi Solar not sure what you mean by " can I stack the VRLA batteries 2 together, if you mean parallel two banks then sure.
It is not the greatest practice but from what I read up to 4 banks is not too bad to parallel.
I have had heaps of parallel banks of Flooded batteries in the past, no real problems.
As long as a cell doesn't short out then all is good. And as long as the battery banks are similar age and capacity.
Hope it all goes good with the repairs when the parts turn up.
Pete
It is not the greatest practice but from what I read up to 4 banks is not too bad to parallel.
I have had heaps of parallel banks of Flooded batteries in the past, no real problems.
As long as a cell doesn't short out then all is good. And as long as the battery banks are similar age and capacity.
Hope it all goes good with the repairs when the parts turn up.
Pete