You guys ever heard of problems arising from backfeeding a generator into a drier 220V (30 amp) circuit?
I've read that as long as the circuit breaker panel is OFF you should be ok. This will prevent sending current out to the workers repairing service and should prevent the generator from exploding when power is restored.
Is this a bad idea? Is there any problems arising from pushing current backwards through a breasker (probably showing my ignorance here)? I assume because the current is alternating this is not an issue?
On 3/9/2014 10:45 AM, email@example.com wrote:
I do that.
First it's illegal.. but I don't care. If you use a lockout ckt it's legal.
You can only power what the dryer line can handle. so if you have 30amp,
I have to shut my water heater, and water pump since both are higher.
It's not to protect the workers.. the solar collectors send voltage out
The real problem is overloading your generator.. The old statement about
the workers doesn't work when you think how many solar panels are up on
roofs these days. The workers always have to treat the line like it is live.
Wrong, on both accounts. It is *precisely* to protect line workers.
Solar collectors *only* produce power when they're connected to the
line. They need the line to synchronize the inverter. You won't find
a line connected solar system that will even produce power when it's
not line connected. They're useless as emergency power.
Wrong, wrong, wrong, and "shit happens". DONT DO THAT!
On 3/9/14 9:39 AM, firstname.lastname@example.org wrote:
This is part of UL 1741.
You won't find
There are solar inverter systems that will charge batteries while
connected and feeding the grid. When power fails, they invert the
batteries and can feed loads in your house just like a generator system.
Similar to wind power, as I understand they need the grid to get the
turbines turning. Once the wind gets about 12mpg they start producing
power and reach efficiency about 20-25mph.
As your lineman if there is back feed from a generator. Chances are he
will tell you his experience with back feed. In some places there must
be an automatic cut of so when the grid goes down the grid is isolated
from the generator, and visa versa.
It's more than that. If the utility is cut even while it's producing,
the generator will stop. It *needs* the line sync to operate at all.
The "cut off" must isolate the line when you're generating power
independently. If you're grid-tied, then you can't generate when the
grid tie is lost. BTW, I *think* (but obviously can't prove the
negative) that it's everywhere. Utilities get very sensitive where
the safety of their crews is concerned. It's dangerous enough without
Wrong on both counts. It IS to protect the workers (although only a
very limites scenario could ever really cause a danger) and the solar
systems do NOT put power out the line in case of a grid failure
because they are"grid tie - and only put power out when power comes in
(simple explanation of a complex system)
On 3/9/14 8:45 AM, email@example.com wrote:
Just to answer your last question, only if the breakers in the current
path are rated for back feeding. Non back feed breakers are usually
marked with an arrow or other indicator of current flow.
On Sun, 9 Mar 2014 07:45:30 -0700 (PDT), firstname.lastname@example.org
Sure, other than being illegal in many areas, it's dangerous. It's
dangerous for the linemen working trying to get your service back (the
reason it's illegal) and suicide cords are called that for a reason.
...as long as. That's the problem. It's too easy to forget.
Yes, it's still a bad idea but not because you're "pushing current
backwards". The "current" has no idea which direction it's going.
Back-feeding breakers is perfectly normal, often done when wiring
Other than frying the linemen, the problem is the suicide cord.
On 3/9/2014 11:27 AM, email@example.com wrote:
So let me ask this... if you connect a 6k watt generator and forget to
throw the switch god forbid, do you think your generator will still try
to feed the grid, mine would simply pop it's own ckt breaker since the
draw would be too high.
As far as ckt breakers working in one direction... Really????
I live in farm country, I have been running a generator for years
illegally .... I never had a problem ...
I do always shut the main off, then all ckts I can't power..
Brian, it's illegal, but it's done all the time.. put a note on your
panel door if you are worried you might forget the sequence.
No, there is no guarantee that it'll "simply pop it's (sic) own ckt
breaker". If your line is isolated it'll happily energize it. When
the power dudes show up they will be greatly, and rightfully, pissed.
Did you even try to read what was written?
"Always" is a long time. History shows that not all do, so it's
So is murder, does that make it a good idea (one that you promote)?
Can you insure that in a lost power situation that the lineman will
NEVER be put into a situation where he comes in contact with the power
from the generator. Remember he only has to be knocked from the pole
to get killed.
Other than frying a line man or gal - but the generator might likely
blow up when the line comes on. The other problem - with the main
turned on you are feeding a transformer on the pole and who knows
the load it has with the neighbors on the high line it connects to.
On 3/9/2014 10:27 AM, firstname.lastname@example.org wrote:
Transfer switches exist for a reason.
They are expensive partly because they do a difficult job and require
a considerable amount of hardware.
OTOH, trying to bypass one to save a few $ is shear follly.
An "interlock" exists for just this application
uses normal breakers and a mechanical interlock that makes it
impossible to turn on the generator breaker with the main on, and
imossible to turn the main on with the generator on.. The only
difference is you don't use the dryer "plug", you use a generator plug
(male plug_ so you don't need a "suicide cord" or "widdowmaker".
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