Your last generator Maintenance Run

[LouNY]

Bonded/floating neutral question

My PTO generator has a bonded neutral. It's quite old so no manual available for it & I'm pretty sure it can't be safely configured to floating neutral.
The main breaker panel in the house obviously has neutral & ground bonded properly. Well, I haven't checked, but it's a safe assumption.

All the fun in Texas & similar issues with ice taking out massive amounts of power lines at my parents back in Oregon have finally motivated me to get around to getting backup power properly sorted & tested. I have a manual generator disconnect switch that was installed with my solar several years ago that I have never used. I went to go pop it open & try to see if it switched the neutral & what not. But it apparently has a lockout so you can't open the box unless it's set to off. I need to crack it open later when a power outage won't tick off the wife.

If the transfer switch disconnects both hots & the neutral from the grid, does that make it correct? Even with the neutral being bonded at the generator & at the main breaker panel? Do I only hook up the 2 hots & the neutral from the generator to the outlet & disconnect box? In either case should I run a ground from the generator to the ground rod? My decent amount of electrical knowledge & Google fu is failing me. Decent amount out there on floating vs bonded neutrals, but I'm not finding diagrams that make sense to me.

No GFCI on the old generator, but I do want to do things safely, which generally means to code.

Most of the older single phase transfer switches were two pole double throw,
all that they separated were the L1 and L2 hot legs the neutrals were all commonly bonded.

(added)
My pto generator manual recommended a grounding jumper from the frame to a ground

 

[TractorGuy]

7 AM this morning.

It was scheduled for 10AM today but power went out just before 7. Not sure what happened but I heard sirens shortly after it went off. Hope somebody didn't crash into a power pole.

I was kind of foggy and didn't follow the start up procedure to the tee. I forgot to heat the glow plugs first. It fired right off but smoked a little since I didn't warm it right. Smoke cleared right up and it went to work. I also forgot to manage loads at the breaker panel before flipping the transfer and we had our 10KW emergency heat strips turned on. Generator gave a grunt and went right to work so it was indeed a good test. Power was restored in 30 minutes or so but I left the house on generator for another 30 before switching back.

On the bright side I didn't have to get the load bank out of the shed to run the test.

 

[3930dave]

Good (unplanned) test TG. That 10kw strip should keep you plenty warm (emerg wise) in N. FL.

Well rested/awake is one thing...... middle-of-night NOW operation is another, even on something simple.

I have a high-water alarm on my sump. One of the reasons I now prefer storing my gens fully fueled is that if that alarm goes off at 3am, I don't want to be stumbling around in the dark sloshing fuel cans.....

Train in Peace..... :thumbsup:

Rgds, D.

 

[TractorGuy]

Bonded/floating neutral question

My PTO generator has a bonded neutral. It's quite old so no manual available for it & I'm pretty sure it can't be safely configured to floating neutral.
The main breaker panel in the house obviously has neutral & ground bonded properly. Well, I haven't checked, but it's a safe assumption.

All the fun in Texas & similar issues with ice taking out massive amounts of power lines at my parents back in Oregon have finally motivated me to get around to getting backup power properly sorted & tested. I have a manual generator disconnect switch that was installed with my solar several years ago that I have never used. I went to go pop it open & try to see if it switched the neutral & what not. But it apparently has a lockout so you can't open the box unless it's set to off. I need to crack it open later when a power outage won't tick off the wife.

If the transfer switch disconnects both hots & the neutral from the grid, does that make it correct? Even with the neutral being bonded at the generator & at the main breaker panel? Do I only hook up the 2 hots & the neutral from the generator to the outlet & disconnect box? In either case should I run a ground from the generator to the ground rod? My decent amount of electrical knowledge & Google fu is failing me. Decent amount out there on floating vs bonded neutrals, but I'm not finding diagrams that make sense to me.

No GFCI on the old generator, but I do want to do things safely, which generally means to code.

My understanding is the circuit should only be bonded at one location. I back feed into a bonded panel with a main interlock on it so I removed the bonding strap on my generator. I still have the generator frame grounded but I don't have that ground bonded to the neutral leg.

I have a homemade load bank I use to test my generator with and when testing it is totally disconnected from the house so I bonded the panel on the load bank. That keeps me from having to reconnect the bonding strap on the generator for testing.

I think most homes are bonded AT the main panel. If the transfer switch feeds power from one source or another to the main panel it doesn't seem like it could or would interrupt the bond there.

 

[3930dave]

Bonded/floating neutral question

No GFCI on the old generator, but I do want to do things safely, which generally means to code.

I don't wire for a living, and am in another country , so all I'll toss out is that unless CO has gotten creative, you should fall under your national electric code.

A really well crafted flow-chart would be a great way to navigate Code, but that's in a perfect world/my dreams...... real-world, we need somebody who's been reading the Code tea-leaves for a recent living near to you to come along.....

Rgds, D.

 

[grsthegreat]

A GFCI on a generator is only required for the 20 amp plug in recepticles. If generator has a 30 or 50 amp twist lock no GFCI is required.

 

[grsthegreat]

A GFCI on a generator is only required for the 20 amp plug in recepticles. If generator has a 30 or 50 amp twist lock no GFCI is required.so if you were to hook the gen to the house panel using a Ep amp twist cord, no GFCI on gen needed. The house circuit outlets will ....probably.... already be gfci protected

 

[Fallon]

A GFCI on a generator is only required for the 20 amp plug in recepticles. If generator has a 30 or 50 amp twist lock no GFCI is required.so if you were to hook the gen to the house panel using a Ep amp twist cord, no GFCI on gen needed. The house circuit outlets will ....probably.... already be gfci protected

It predates GFCIs being required anywhere I'm pretty sure. It has a 110v outlet a 50@ 110/220v & a 100@ outlet. I finally finished changing the ancient wierd pin & socket plugs over to the Anderson plugs that modern Winco generators use.

I'm not worried about the lack of GFCI, mostly worried about how to properly handle the bonded neutral on the generator. Code says you can only bond ground & neutral in 1 location. I can't unbond it on the generator. I'm pretty sure the disconnect doesn't switch the bonding in the house breaker panel & wiring that up doesn't sound feasible or withing my skill level.

I see all sorts of discussions about NEC Separately Derived Systems & switching neutrals. But am still not clear on how to do it properly. I know you don't ever want power flowing through ground, so you only bond it in 1 place. Bonding it in multiple places means power can flow through ground and/or neutral, causing problems.

 

[Alan W.]

Our electric is usually good about no outages but when we do have them its due to the weather and they can be extended.
Ours went out the other night after the ice storm.
Since it was late I decided to fire up my old Tecumseh powered coleman to watch tv then go to bed. Its old but has been good needing only brushes replaced.
It fired up fine I ran a cord to my surge suppressor for the tv and plugged it up.
It hummed and fire shot out then all the smoke came out.
Generator was putting out 156 volts. Need to check voltage before plugging in.
Luckily I have multiple generators and the tv was unharmed.

 

[3930dave]

Quite the show Alan.... but not the one you wanted to see !

More proof these things run on Smoke !

I think it was daugen (or....) who posted some low cost plug-in Vac displays..... your pyrotechnics is a good example of why I should have them here by now....... good to have one sitting in the front of the generator, circumventing the need to get a DMM out....

Rgds, D.