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Greetings from central Maine everyone; first post here. I recently purchased a 28 kw genset with a 3-cylinder Deutz diesel engine and a Lima SER alternator. The unit appears to be mint and the alternator is built like a russian tank. It has six field segments and 12 wires coming out of the stator, so it can be wired in a plethora of ways. Currently, I have it wired as a low voltage wye config., 3 - Ø which produces 120V between neutral and L1, 2 and 3, and 208V between L1, 2, and 3. I really would like it to put out the full 28KW in 120/240V, single-phase. The manual lists 3 possible single-phase configs; a low-voltage delta, which only puts out 120V between L1 and L2 (acceptable, but not ideal); a 240V zig-zag which mimics a regular house entrance schema, and a high-voltage, 480V zig-zag, which is useless to me. My question is this: can either of the single-phase configs yield the full 28KW? My imperfect understanding after researching is that wiring a 3 Ø generator to single-phase limits the output to about half it's rated capacity, but it appears from the schematics that in both the relevant single-phase configs, all 6 stator segments are wired into the circuit. Thank you in advance for any light shed. I can provide more info if needed.
 

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Sorry I don't know about the Wiring. Hopefully someone will be along that does know and caan help you out.
 

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Thanks for the welcome! I'll stay tuned to see what develops. Besides, if I don't like the replies I get, I can always ask for my money back, right? :)
 

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Most Any generator with a 12 lead stator, will be safe to operate at 66.6% of it's 3 phase rating, on single phase. Some units are 100% either way but those are wound different than most, an will be so stated on the ID plate. In the case of your Lima, wire it 120/240 dog leg (zig-zag) and you will be safe to about 70% or greater, depending on ambient air temp. The reason you can't get 100% on most is do to the fact you are not using all 6 coils, an the amperage (100% rating) will exceed the stator windings rating per leg. Remember the engine only operates in KW, which is true power. The alternator only knows Kva which is apparent power. Also 99.999% of gen-sets wired for 3 phase are rated at a 0.8 lagging power factor. While 99.999% of single phase units are rated at Unity which is a 1.0 power factor. All the above said, wiring the unit 3 phase low Y, (120/208) an bringing the voltage to 220Vac phase to phase, which will yield a phase to neutral of 127. These voltages will run any anything that has a 120/240 voltage rating. There will be an imbalance within the gen alternator but it will not hurt a thing. Hope this helps, Kenneth
 
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