interesting talk to my meter reader today

[mobile_bob]

he came by with a trainee, then poked his head into my shop and asked if the shop was on the same meter as the house.

i told him yes

he then went on to say my meter was reading the exact same as last month!  (oh really?  is that right?)

playing dumb as i thought something was amiss about 2 weeks ago when i was out in the yard doing some weedeating and happened to be trimming around the meter head when the airconditioner came on... i naturally looked up to see how fast the meter would be spinning and found it stalled.

i guess the old sangamo spun its last spin sometime over a month ago.

going to be interesting how they calculate my last months bill, and yes i will be watching for that bill real close.

too funny

bob g

ps.  i can't wait for them to get used to the idea that there new meter is going to be turning very slowing soon, as i am going to be using nat/gas and solar for power production for a while to see what the offset might be.  so in the end this failed meter might not turn out to be so amusing to me, they may think i have been doing something that whacked out their old meter and then when the reduction takes place they may think they need to get into the weeds with me to find out what the heck is going on.  should be fun.

[Jens]

Yup, always in the mood for a good scrap ....

[Tom Reed]

Good thing they'll be replacing it, it's hard to run a stuck meter backwards.  I just hope you don't get the smart meter upgrade!

[glort]

My Neighbours meter died a few years back.
Took them a bit to pick it up but then they billed her based on the last 3 years average power consumption for those months.

They put in a new meter that was wacko.  She got a bill for $4700 odd bux.  I rang the power company for her and explained she was an old lady living on her own in an old house that had limited wiring capacity and had no major power consuming appliances and gas hot water.  The person I spoke to was skeptical and said they could send someone out to test the meter but if it was OK she would have to pay for the testing. I said if it came up OK the next stop would be the Ombudsman as there was no way she could use that much power in a month.

They came out and found the meter was off it's face so installed yet another one.  I gave the installer some grief about the distress and worry it gave the old girl and she got a letter saying the meter was faulty and they would not be charging her anything for that months power.
Bugger me if the next bill didn't come in about 4 times higher than normal as well.

I had a look at it and the person that read it clearly was blind as the thing wasn't reading near what was specified on the bill. Back out they came, confirmed it was a reading error and they charged her the correct reading till that time, ( a week after the first reading) and all has been fine since. Thank god.


Years ago a Friend of mine rented a place in a small town he got posted to for work.  The power was on when he arrived and the owner said he would pay the bill till that time to save the disconnect/ reconnect fee.  No Problems.
My after some months, my friend couldn't believe how cheap his power was.  The bills had been put in his name but were all VERY low.
There was a problem with the hot water one time when I was visiting and we went out to the fuse box to turn the power off so I could pull the element to replace it.
I noticed the cover on the meter was loose where the connections were so I pulled it off for a stick beak.

Someone had Jumpered a wire across the terminals of the meter. The normal connections were there but there was a piece of thick wire going across that meant the power could bypass the meter without registering. This explained the cheap bills.  Not being Qualified to work on such things  I replaced the cover, tightened it up and got on with replacing the heater element.
Mate always did have dirt cheap power bills in that place!

I have been doing a bit of home generation to offset my power bill using a 3 phase motor on one of my little Diesels.  I can get the meter to run backwards but when you work it out, it's a low paying practice. The bills seem a lot but it takes a lot of hours to make much difference when you work out you are making about .4oC worth of power an hour.

I'd like to get a big motor, say 15 KW so I could pump a solid 10Kw back into the grid and really get the meter spinning in the Right direction for me and the wrong one for the power extortion company.  The meter is good for 60A so would handle that easily. I'd have to install a HD Circuit and wiring or run the power back through multiple circuits which would be a little less work too hook up.  I have loads of circuits here so wouldn't be hard to tap into several if I sited the genny appropriately.

[LowGear]

I have been doing a bit of home generation to offset my power bill using a 3 phase motor on one of my little Diesels.  I can get the meter to run backwards but when you work it out, it's a low paying practice. The bills seem a lot but it takes a lot of hours to make much difference when you work out you are making about .4oC worth of power an hour.

Don't happen to have a drawing do you?  At first I thought "Why is he only getting 1 KWH of power and then I realized he wasn't paying 43 cents a KWH.  I'm thinking something like this:  http://www.ebay.com/itm/290978310544?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649  OK!  I said "like".  I'm pretty sure that "free shipping" would sink like the Titanic on it's way to Hawaii.  I've already got one of those meters that do a lot to keep tract of the solar grid tie.  I'm in the 18 megawatt range right now.  So the math goes 18000 * .43 = $7,740.  So I guess there is an up side to assuming the position every month when I pay the electrical bill.

Casey

[Jens]

The only thing legal as far as I know is a grid tie inverter and those things are damned expensive when you get a decent amount of power capacity.

[glort]

I pay a bit under .20C a KWH so I was fudging the figures a bit to say I do get .40C worth of power an hour because I only run about 2 Kwh due to the wiring limitations and the engine I'm using.

The motor you linked to looks Fine. Any 3 ( or single phase with modifications to the cap)  phase Induction motor will do.

I don't have drawings for anything I have done.
My drawing skills are so bad its far easier for me to make something then photograph it than draw the damned thing.  I was actually intending on pulling it all apart in the next day or 2 as I'm having a big clean up and want to be able to relocate my toys inside the shed instead of under tarps in the yard. If you are interested I'll try and shoot some pics of the dogs breakfast wiring but I warn you it isn't pretty. 

I have just been playing with it in a temporary setup as proof of concept which is why I now would like to move stuff up the garage and make it a bit more professional.

There is plenty online and you tube about it. Be warned though, there are a lot of people with no real knowledge posting their incorrect thoughts as fact telling people things can't be done that are rather basic and done every day. I say a couple of people repetitively talking crap that I'd like to hook up to my setup. If it can't be done, then they wouldn't have anything to worry about would they??
Idiots!

This site has a pretty good explanation for stand alone operation.

http://autonopedia.org/renewable-energy/generators/motors-as-generators/

I had links to other sites but I sort of got the theory, so for some time have been doing the practical experimentation and I can't find the sites I'm looking for now. 
It is very easy though. You pretty much hook the motor up as you would to drive something then spin it up with the engine a little slower than it would normally run ( as on the name plate)  then when the power is connected you speed the engine up to over drive the motor and it starts to generate.  The mains basically phase locks the motor and the faster you turn it, the more power you generate up to about 80% of the capacity of the motor you are using.


I have a bunch of Grid Tie inverters I could use but not sure if they are worth the bother.  I'd have to rectify the AC power to DC for a start and then split it.
I have 4x 2000W and 1x 3600W inverters.
When You could get solar systems with a .60C feedback tariff I was tempted to get the smallest one available and hook in the genny to make it look like I was getting an efficiency never seen before or 6 hours of extra clear sky sunlight over and above everyone else. 

Now the feed back tariff is reduced to a useless .6c Kwh the best value is spinning the meter backwards and using the grid as a battery to offset what you use.

[LowGear]

I have a SMA 7000 watt inverter.  The part I'm having trouble with is the three phase generator head and rectifier.

And while the local electricity monopolier is mandated by law to accept solar neither they or the electrical inspectors are open to a waste oil old fart site built system.  Anyone know of a UL listed rectifier in the 5 KW range?

Casey

[glort]

I have a SMA 7000 watt inverter.  The part I'm having trouble with is the three phase generator head and rectifier.

And while the local electricity monopolier is mandated by law to accept solar neither they or the electrical inspectors are open to a waste oil old fart site built system.  Anyone know of a UL listed rectifier in the 5 KW range?

Casey

Not sure what power you are wanting to work with now but here are some rectifiers you could use.

http://www.ebay.com.au/itm/3-Phase-Diode-Bridge-Rectifier-40A-1000V-SQL40A-Silver-/120701643698?pt=AU_B_I_Electrical_Test_Equipment&hash=item1c1a60ebb2&_uhb=1



http://www.ebay.com.au/itm/SQL50A-3-Phase-Diode-Bridge-Rectifier-50A-Amp-1000V-Uerla-/150962642243?pt=AU_B_I_Electrical_Test_Equipment&hash=item2326131d43&_uhb=1


http://www.ebay.com.au/itm/Bridge-Rectifier-3-Three-Phase-Diode-100A-1600V-SQL100A-/161009643979?pt=AU_B_I_Electrical_Test_Equipment&hash=item257cec31cb&_uhb=1

If you needed higher power rectification, you could double up with single phase units and run a pair on each leg.

http://www.ebay.com.au/itm/10-x-KBPC5010-50A-1000V-Bridge-Rectifier-Diode-10-grams-of-Heat-Sink-Compound-/281065178275?pt=LH_DefaultDomain_0&hash=item4170ca44a3&_uhb=1


Overkill for what I believe you are proposing.
Remember, each leg is only doing 1/3rd of the total power output after the derating of the machine. As a generator, the 5 HP motor you linked to is only going to be 3.7 KW as a motor and probably around 3KW or a bit less as a generator.  If you want to take full advantage of a 7Kw inverter and have the engine to drive it, I'd be looking at something like a 15 HP induction motor  so you have a bit up your sleeve and can under drive the thing ratings wise or bump the caps up to get better efficiency without cooking it.

7000w /110V is 63A and at 220 is 32A roughly.  Easily within the scope of the 100A 3 phase rectifiers.


One leg from each terminal on the motor goes to the one of the 3 terminals on one side of the rectifier and the other 2 go to your inverter. Just check the voltage input on your inverter. Mine all max out at 600V but yours may be lower. Our Power is 240 Single phase and 415 3 phase  so I don't know if inverters sold in the US would be the same or derated.  I suppose your motors will be similar so they should pair up but check the numbers. Also Check if the unit has dual inputs. Some have to have the total input split through 2 or more inputs. Obviously internally they are 2 smaller units paired together. If the input is split, just run the input wires to both or more input connectors and it will balance itself out.

You would also have to run a cap on the motor to keep the windings excited as I believe the inverter will effectively isolate the induction motor. You'll want 440V or whatever you can get higher rating caps and make sure you limit your voltage under that.  Voltage is controlled by the amount of capacitance you run and the speed you drive the engine as well as whether you are running start or delta hook up but you wouldn't have to worry about that in this case.

For a 5 HP motor you would want something around 25-50 UF. I run the high side because it excites easier and makes more stable voltage in stand alone operation. It can make the motor over heat if you go too high though so you have to watch it with the loads you are running.  In this case it would be very constant so it would be easy to test.  As long as the motor is cool enough to hold your hand on, it's fine. The rule of thumb is run the thing for an hour and if it's cool enough your good.
You can vary the value of caps by running them in series or parallel  which also allows a bit of tuning if you have a few the same values and further tuning if you have different ratings.
Also make sure you use motor RUN capacitors NOT motor START caps. You'll be left under no doubt If you use the wrong ones and neither will your Mrs when she comes to do the laundry and finds holes in your shirt and skid marks in your shorts.


I looked up the regs here for self generation as well and they don't want you doing it either unless you are a commercial enterprise.  They apparently they only allowed solar buy back because it was mandated as a green goober save the planet load of garbage and even the Gubbermint pulled out of that ahead of time when they figured out what it was costing them in tariffs.
I take it you are going to be using a free fuel like WVO/ WMo etc for this? If you are thinking or running Diesel, forget the idea now. It won't be cost effective even at your relatively scary power prices.

[thomasonw]

<SNIP>
. . . It is very easy though. You pretty much hook the motor up as you would to drive something then spin it up with the engine a little slower than it would normally run ( as on the name plate)  then when the power is connected you speed the engine up to over drive the motor and it starts to generate.   . . . .

I was always under the impression there was a safety issue with this simple approach, in that if the power-company had a line-out issue - your local generator would keep generating and energize the local segment of your power feed.  Making a safety issue for line-crew when they thought the 'severed' lines would be unpowered.   It is my understanding that detection of this, and disconnection, was one of the key feature of a 'grid tied' inverter.  And that a simple overspun inductor motor lacked this safety feature.

Is this not true?  (I really do not know, and that might be part of the 'misinformation' out there  )

-al-

[Dualfuel]

just a comment about the motor/generator safety thing....and this goes for generators without transfer switches...yes they are dangerous if your power is running out to your transformer and off down the line but...if your neighbor has any load on his transformer or the guy down the street...your motor or generator is dead meat anyway...what you have won't power the block and will go poof!
DF

[glort]

<SNIP>
. . . It is very easy though. You pretty much hook the motor up as you would to drive something then spin it up with the engine a little slower than it would normally run ( as on the name plate)  then when the power is connected you speed the engine up to over drive the motor and it starts to generate.   . . . .

I was always under the impression there was a safety issue with this simple approach, in that if the power-company had a line-out issue - your local generator would keep generating and energize the local segment of your power feed.  Making a safety issue for line-crew when they thought the 'severed' lines would be unpowered.   It is my understanding that detection of this, and disconnection, was one of the key feature of a 'grid tied' inverter.  And that a simple overspun inductor motor lacked this safety feature.

Is this not true?  (I really do not know, and that might be part of the 'misinformation' out there  )

-al-

Yep, another one of these dreamed up from god knows where load of crap that people spread around like it's fact.
Clearly they don't have the first clue what they are talking about let alone any hands on experience.

I have read people saying that other devices on their home circuit have sufficient capacitance to keep the induction genny powered.  I think that would not be typical and you would have to have the exact right combination of load and devices to do this.  I put it at a very long shot personally and think it would only happen with a large motor being used as a genny to be able to cope with the switching loads anyway.

The thing about being able to power miles of power line is ignorant garbage because of the what Duel points out.  The power goes and suddenly your genny is being called upon to power ever device connected to the grid between you and the breakage.  Even if you are just trying to power the neighbours either side of you, the resistance in the power lines are probably going to be enough to make the induction motor loose excitation not to mention dropping the extra load on the thing.

This fable also relies on the line man not checking the wires before he touches them which is ignorance in the extreme. No one is going to start working on lines they have not tested. From what I have read in several places, they also fit cables to both sides of the wires to short them out in the case of back feeding or residual capacitance.  To just think that everything attached to the grid was working perfectly and had not failed in it's lockout would be stupidity beyond belief not to mention one hell of a stretch of the imagination in todays over the top health and safety practices.

The grid would have to fail on the pole your home is wired to in order to be able to energise any lines. To think a small induction generator is going to energise miles of lines even without any load is just wishful thinking even if you set out to do that.

[LowGear]

Belief and faith.  Those words are so easy to write and say.  You're telling me those itsie-bitsie rectifiers will handle 5-6 kilowatts of power (I might break down and just buy a three phase generator)?  How do you connect 10 gauge wire to them?

WVO and biodiesel are on the plan board.  My Witte manual under fuels reads "Do not use Crude."  That's the entire fuels section of the manual. 

Casey

[glort]

Belief and faith.  Those words are so easy to write and say.  You're telling me those itsie-bitsie rectifiers will handle 5-6 kilowatts of power (I might break down and just buy a three phase generator)?  How do you connect 10 gauge wire to them?

WVO and biodiesel are on the plan board.  My Witte manual under fuels reads "Do not use Crude."  That's the entire fuels section of the manual. 

Casey

Is this a rhetorical Question?

If so, I'm not telling you they will handle the power, the manufacturers are. As I have seen people using the things on the net for their power supply setups, I take it that they will handle the power as stated.

As far as connecting wire, If you have a look they have the push on type connector terminals. Get some female spade terminals and crimp them on your wire.

By all means, If you find a better or more durable solution, please post up the details for everyone.