Re: Reminder: Never connect a generator to home wiring without transfer switch

[Mel Beckman <mel () beckman org>]

> The point that several brought up is that doing so is not only a bad idea, but that it simply won't work 

Jay,

I’ve had this scenario play out several times:

DIYguy: Check out my new generator! It’s big enough to power the whole house!

Me: You run extension cords from the generator to all your devices then?

DIYguy: No need! I built this special “suicide cord” I read about online in a prepper forum. I just plug that into any 
wall outlet and it powers the whole house!

Me: Um, you haven’t tested this, have you?

DIYguy: Sure. I fired up the generator and plugged the dryer into it. Works a treat!

Me: No, I mean your special cord. Have you tested that?

DIYguy: Hey, if it'll power the dryer, it’ll power my whole house. No need to test!

Me: Ok, first of all, that’s not a “suicide cord”. That’s a “homicide cord”. Second, …

The problem with this scenario is that the DIYguy never finds out that it won’t work, at least not until the trial. :)

 -mel


> On Aug 30, 2021, at 11:25 AM, Jay Hennigan <jay () west net> wrote:
>
> On 8/30/21 10:46, Aaron C. de Bruyn via NANOG wrote:
>
> > While they were waiting for a few more trucks to arrive with a replacement pole, I got to ask them a few questions.  
> > They said it's standard practice for them to ground on both sides exactly for the reason that someone might 
> > accidentally connect a generator.  They open the nearest switch on the upstream side, test to make sure the line is 
> > dead, install grounds on all the wires, then test the downstream side and attach grounds to all the wires, 
> > effectively making the work zone an isolated segment.
>
> I don't think anyone participating in this forum was remotely close to suggesting that anyone connect a generator to 
> home wiring without a transfer switch in place. It's stupid and dangerous.
>
> in the vast majority of power outage scenarios. Unless the outage is on your service drop or on your pole pig, the 
> impedance of the neighborhood or city downstream of the outage as reflected through the transformers will vastly 
> overwhelm any portable generator capable of being connected with a "suicide cord" by several orders of magnitude.
>
> The other point is that, assuming that the utility is following their safety protocols, the utility worker is going 
> to ground the load side as well as the incoming feed specifically to prevent backfeeding the grid from a miswired 
> generator.
>
> Yes, never connect a generator to home wiring without a properly installed transfer switch.
>
> Yes, the utility workers should ground the load side to avoid being killed in the event that someone does so.
>
> Yes, if the utility follows all procedures correctly, and you happen to connect your miswired generator at the exact 
> instant that the utility worker removes the ground after making the connection, and said worker grabs the conductor 
> with bare hands, and there's a path to ground through the worker's body at that instant, that worker is probably 
> going to die. The probability of this happening is somewhat greater than that of winning the lottery, but if they're 
> on a pole in the middle of a storm working on overhead wires, the odds of their being struck by lightning are also 
> worth considering.
>
> It's a warning worth repeating, but probably not to this extent.
>
> >    This is NANOG -- I'm sure that we've all followed a set of steps
> >    perfectly and still managed to redistribute BGP into the IGP, or
> >    apply an ACL and lock ourselves out of a box, or types "show run"
> >    and watched the router randomly reboot. 
>
> Don't forget the classic "switchport trunk allowed vlan" vs. "switchport trunk allowed vlan add".
>
> -- 
> Jay Hennigan - jay () west net
> Network Engineering - CCIE #7880
> 503 897-8550 - WB6RDV