Setting up an MEP-003A as a permanent stand-by Generator

[Guyfang]

Thats why we run grounding strap all the way around the house poured concrete floor, then fill it with concrete. One end comes up at a central ground point in the house/cellar. Everything that gets grounded in the house, gets hooked to the central ground point.

 

[Scoobyshep]

Thats why we run grounding strap all the way around the house poured concrete floor, then fill it with concrete. One end comes up at a central ground point in the house/cellar. Everything that gets grounded in the house, gets hooked to the central ground point.

Grounding in my opinion, is a subject that could be better covered. Over here residential grounding is 1 rod 25 ohms or less, or 2 rods both need a minimum of 8 feet of soil contact. So you could have a very high resistance ground and still be up to code. One of my old coworkers used to urinate on the rod right when the inspector would arrive to get it wet so it would test low enough.

 

[Mr4btTahoe]

Got home and my wire had arrived... so fired up my old back-hoe (as in my back... my hoe.. and my shovel) and got the trench dug and conduit/cable in the ground.

Good times. Panel will be here Saturday so I should be all tied in and good to go by the end of the weekend.

No... its not real deep. I'd say 8-12" depending on if I hit roots or limestone. The area its in wont be dug.. its also urd cable in sch 40 1.5" conduit the full run. Not too worried about it.

More to come.

 

[islandguydon]

It seems my point is mistaken, In the commercial Security Gate business when you back hoe the footings for the piers you always pour the forms for the mechanical. This includes the master / slave conduits, power, telephone and fire dept override for the electronic KNOX access for emergency ingress. In the form with everything else electronic is the 8' ground rod so all the electrical equipment has an adequate ground. This procedure is repeated on both sides of the gate system to insure good grounding. I AM NOT SAYING TO GROUND TO THE CONCRETE PAD AT ALL, I'm saying a generator is a stand alone system same as any security gate, weather its a single family home, a gated community or a commercial application. Its just a cleaner install when all devices including the ground rod is all incorporated under the mechanical on a concrete pad so it is protected from any gremlins. Placing a ground bond to a concrete pad alone is insane. That's all.


Here are a few examples of my personal gate, and for a good view of the mechanical pads for a commercial application. Both applications are stand alone with the ground rods IN the concrete pads they are mounted on. The generator is a stand alone as well. That's my humble opinion.

 

[Mr4btTahoe]

It seems my point is mistaken, In the commercial Security Gate business when you back hoe the footings for the piers you always pour the forms for the mechanical. This includes the master / slave conduits, power, telephone and fire dept override for the electronic KNOX access for emergency ingress. In the form with everything else electronic is the 8' ground rod so all the electrical equipment has an adequate ground. This procedure is repeated on both sides of the gate system to insure good grounding. I AM NOT SAYING TO GROUND TO THE CONCRETE PAD AT ALL, I'm saying a generator is a stand alone system same as any security gate, weather its a single family home, a gated community or a commercial application. Its just a cleaner install when all devices including the ground rod is all incorporated under the mechanical on a concrete pad so it is protected from any gremlins. Placing a ground bond to a concrete pad alone is insane. That's all.


Here are a few examples of my personal gate, and for a good view of the mechanical pads for a commercial application. Both applications are stand alone with the ground rods IN the concrete pads they are mounted on. The generator is a stand alone as well. That's my humble opinion.

I'll say this about grounding... when I did my grid tied solar install, I spent months studying the NEC. ALL ground rods MUST be bonded to the main service entrance ground. Its common practice for large pieces of equipment such as a generator to have instructions stating to drive in a separate rod... problem with that is unless that equipment is completely isolated, during lightning strikes, power in the ground will want to equalize... as it radiates out from the strike point, voltage gradually decreases. When one rod is at one voltage... and the rod at your service entrance is at another voltage, they will want to equalize. If they are not bonded, that voltage spike will back track through the chassis of the equipment... into the conductors until it reaches the main service entrance. This causes severe damage throughout the system.

Now if the system is isolated... no conductors back to a grounded system, its not an issue. Code used to allow separate ground systems for lightning protection and such... best practice and code are two different things.

Anyways.. if you drive a ground rod near a piece of eqyipment, always bond it to the main ground system with properly sized GEC. If the unit is grounded at the main panel, it isn't necessary for an additional rod to be driven unless the ground system is lacking.

 

[Lovetofix]

I just saw this thread and thought I would mention something I wish I had done with my install.
That is to run an extra wire along with the main wiring to supply power for a battery maintainer. You already have a ground and you said the neutral will not be switched so you might only need one extra conductor, but I would just use a length of Romex to be safe.

And if you ever want to incorporate auto/remote startup run a smaller two conductor wire for switching control.


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[Guyfang]

Grounding in my opinion, is a subject that could be better covered. Over here residential grounding is 1 rod 25 ohms or less, or 2 rods both need a minimum of 8 feet of soil contact. So you could have a very high resistance ground and still be up to code. One of my old coworkers used to urinate on the rod right when the inspector would arrive to get it wet so it would test low enough.

This is SOP in Ft. Bliss, El Paso. The "Mens Room" is what some called it.

 

[Mr4btTahoe]

Progress!

The unit is now under shelter and wiring has been ran. Im pretty happy with the outcome so far. Got it anchored to the pad as well.

Panel will be here tomorrow supposedly. We'll see

 

[Scoobyshep]

Progress!

The unit is now under shelter and wiring has been ran. Im pretty happy with the outcome so far. Got it anchored to the pad as well.

Panel will be here tomorrow supposedly. We'll see

Not bad, The only comment I would make is there is no flex installed in the conduit. might have vibration problems.

 

[Mr4btTahoe]

Not bad, The only comment I would make is there is no flex installed in the conduit. might have vibration problems.

I thought about that but with how much wiggle this conduit has (not anchored), I don't forsee a problem.
We'll see. It may crack the conduit in a few years and if it does or if there is a lot of movement, I'll get a section of flex for it.

Made some progress today... got the panel changed but found that I need to pull a neutral from the main as the original sub I replaced was setup as 240v only.

I'll do that next week.

 

[Scoobyshep]

I thought about that but with how much wiggle this conduit has (not anchored), I don't forsee a problem.
We'll see. It may crack the conduit in a few years and if it does or if there is a lot of movement, I'll get a section of flex for it.

Made some progress today... got the panel changed but found that I need to pull a neutral from the main as the original sub I replaced was setup as 240v only.

I'll do that next week.

You need a bushing in the back of that panel

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[Scoobyshep]

I thought about that but with how much wiggle this conduit has (not anchored), I don't forsee a problem.
We'll see. It may crack the conduit in a few years and if it does or if there is a lot of movement, I'll get a section of flex for it.

Made some progress today... got the panel changed but found that I need to pull a neutral from the main as the original sub I replaced was setup as 240v only.

I'll do that next week.

And if that is the first means of disconnect you might not need a neutral. Big question to know for sure on that is whats feeding this panel?

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[Mr4btTahoe]

And if that is the first means of disconnect you might not need a neutral. Big question to know for sure on that is whats feeding this panel?

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It does need a neutral as this is technically a sub panel. Its powered by a 400a meter base with 3 main breakers... 200a to the house.. 100 to the shop and 100 to this panel.

I'll get a bushing for the panel. The one I pulled didn't have one either and it was just changed by an electrician so I didn't give it any thought. I'll add the bushing when I pull the neutral.

 

[Scoobyshep]

It does need a neutral as this is technically a sub panel. Its powered by a 400a meter base with 3 main breakers... 200a to the house.. 100 to the shop and 100 to this panel.

I'll get a bushing for the panel. The one I pulled didn't have one either and it was just changed by an electrician so I didn't give it any thought. I'll add the bushing when I pull the neutral.

Definitely need a neutral. Also be sure neutrals and grounds are separate. Make sure the neutral buss is not bonded to ground. Otherwise looking good.

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[Mr4btTahoe]

Definitely need a neutral. Also be sure neutrals and grounds are separate. Make sure the neutral buss is not bonded to ground. Otherwise looking good.

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No neutral bond at this panel and I added the ground bus and it is isolated.

 

[Scoobyshep]

No neutral bond at this panel and I added the ground bus and it is isolated.

Good work.

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[shawn77901]

This is SOP in Ft. Bliss, El Paso. The "Mens Room" is what some called it.

LMAO I live in El Paso, CAN CONFIRM that's something that would definitely go down here!!!

 

[Mr4btTahoe]

More progress but no pictures at the moment.

Was finally able to get my hands on the single conductor wire needed to pull the neutral from the 400a Meter/Main panel to the 100a subpanel/generator panel. They didn't have #1 aluminum in stock so went with #3 copper. Our hvac guys let me run it through their account so the price was decent.

Now all that is left is to isolate the neutral at the generator and connect the neutral for the generator at the panel.

Then I start the fun process of running the new circuits for the fridge, freezer, water heater, etc. Hopefully I'll get that buttoned up this weekend.

Also ordered the parallel tee taps I'm going to use to setup the load bank panel. I'll be using the small panel I removed as a "Load Bank Panel"... I'm going to use the parallel tee taps to tap the leads from the generator before the 60a breaker in the panel. Those taps will feed the load bank panel. Inside that panel will be 3 20a breakers used to power the heater elements to load test the generator.

That way I can run the unit under load without changing any wiring and not using anything in the house as the load. Being fed from before the 60a breaker means it'll be directly fed from the generator. Eventually, I'll use these heaters in a solar water heating tank so none of the energy being used is wasted. Win win.

 

[Mr4btTahoe]

Made some progress this weekend.

Isolated the neutral at the generator and finished wiring it up. Its done and ready to go electrically anyways. Need to get new batteries and I want to get a spin on oil filter adapter for it yet.

Got most of our new circuits ran (instead of isolating original circuits). I added in new outlets/dedicated circuits for the fridge, freezer, entertainment center, and comms/computer area. I mounted the outlet for the fridge just slightly out from behind it so its accessible for the coffee maker or microwave if need be.

All that is left is to pull the circuits for the stove and water heater and re-route them to the gen-fed panel.

I purposely used black outlets to signify they are from the generator panel. All ran with 12/2.

I purposely put both fridge and freezer breakers on the same bus in the box. I will also be adding a 30a 110v breaker on that bus which will allow me to power the important things using our small 3500w inverter generator that is extremely quiet and sips fuel. That way we can run the big unit during the day to heat water, cook, etc.. but at night, switch over to the fuel sipper quiet unit and just keep the food cold and a few lights if need be. Also if power is only going to be off an hour or 2.. no point in running the big unit.

More to come.

 

[Mr4btTahoe]

Pretty well buttoned up. Added a 30a 110v breaker and outlet to the main panel that feeds the bus that both the fridge and freezer are on. That way if needed, I can run my small inverter unit and keep things quiet.

I also tied in the load test panel permanently. It's fed directly by the generator using parallel tee taps before the backfeed breaker. This way, I can put a load on the unit without changing anything and without shutting off power to items in the house. Should work out nicely.

Still have a few circuits to run but overall, am happy with the outcome.