help using all 3 phases of 804b

[SCSG-G4]

A fool and his money are soon parted. He can have it good, fast or cheap, or any two in combination, but not all three. To use that generator, he will need three separate circuits, each a 110-120 v only (IE ABSOLUTELY NO 220-240 v ANYTHING) with each drawing about the same load all the time. If he can live with that, more everything to him. If he can't, then he's spitting into the wind.

 

[LEOK]

I was just looking through gov planet they don't have single running 803 available all were no start or parts missing, guess the party is kind of over. I'm glad I got my 802a

 

[Demoh]

Well that escalated quickly.

So Ill bite, but I am probably going to be a little off base or the solution is astronomically expensive. (or borderline dangerous)... This would be uncharted territory for me so just talking theory.

So we want to take balanced 3 phase to run some single phase stuff. It isnt really possible due to phase angle and summing leads to zero, etc... But going to 2 phase (which for almost everybody except furnace applications doesnt exist) which is 90 degree phase angle, If you had an equal split of loads you could use balanced 3 phase power. This is done by a Scott T transformer / Scott T connection and gives you 2 90 degree apart phases which when loaded equally will equally load the 3 phase primary side which is fed by the generator.

So like in a wye connection if we sum 120 degree 120v windings we get 208v, wouldnt theory dictate that if you sum 2 Xvoltage 90 degree windings you would get some higher voltage which would load the generator equally as well? Well it doesnt and causes some issues with this type of transformer. (i forgot the reason, but I think it has something to do with tanking efficiency or offbalanced currents)

Those transformers arent off the shelf transformers. Cost more than a new generator with a 12 wire head. And right now my head hurts from all of that.

The real recommendation would be to get something that is 12 wire. Im rebuilding a 006a right now for my office, we have 240 delta with a high leg (A-C is center tapped for the neutral) to our building and current generator is single phase and not big enough. I am using a 006a because its 12 wire and I will be rewiring it to match the building or just go single phase like the existing generator. We looked at wye to delta transformers and having the poco change our service to wye (we have no use for delta, we arent "industrial" like the previous owner and arent all motor loads) are both expensive options.

 

[Demoh]

I was just looking through gov planet they don't have single running 803 available all were no start or parts missing, guess the party is kind of over. I'm glad I got my 802a

It comes in waves, sometimes theres hundreds, sometimes theres none. Lately its been a lot of 802s. I only have 2 803s left... Im sure another wave will happen after everything rebounds from the stunt RB did with their mega auctions lately.

 

[Guyfang]

A fool and his money are soon parted. He can have it good, fast or cheap, or any two in combination, but not all three. To use that generator, he will need three separate circuits, each a 110-120 v only (IE ABSOLUTELY NO 220-240 v ANYTHING) with each drawing about the same load all the time. If he can live with that, more everything to him. If he can't, then he's spitting into the wind.

I agree, 100%. I would go back to message #18. But then I just fix gen sets.

 

[Light in the Dark]

I'm really surprised, you guys jump right in fixing your units which is much more complicated than this project. I was hoping somebody else had thought of some thing I hadn't.

The concern with providing the information you are seeking is "liability". I hope you determine a wiring solution thats best for you.

 

[DieselAddict]

There are a couple of MEP004s on fleabay just north of me in Virginia. They look dirty but the listings indicate they run and make power.

A little time to clean them up and go through them and you might have exactly what they need. They are under $2.5k each.

 

[LEOK]

Took a new direction a single phase 15k unit based on Kubota v1505-e4b governed 25hp diesel and Mecc alte NPE32D4 with Digital DRE1 regulator which talks via Modbus to dynagen TG410 controller. It will be able to mimic most if not all the mep functions including on board tank refill got sound enclosure also. Learned allot playing with mep and not really liking the generac 15k unit, comes in at the same cost.

 

[FloridaAKM]

The generac 15K unit is mostly for construction site work. I bought two of them many years ago & one went to work to supply whatever was needed during operations. It worked fine until it was hooked up to the Plant IT UPS system. The dirty power coming out of it fried half the battery backup system which was not cheap to replace. This was during the 4 hurricanes we had in 2004, so it was bad timing to discover that issue. Good luck with your new generator system that will actually do what is required of it safely.