Hercules ZXB Military Genset

[lockeowner]

I need a little help identifying a military genset. It is powered by a Hercules ZXB-5 engine, and produces both 60 and 400 cycle 120volt current. The engine is cooled by a squirlcage fan driven by the front of the engine with the radiator mounted on top. It is crank start. I restored it about 20 years ago and use it once in a while, but I've never seen another like it. I also don't know what the total output is. The gauges include frequency, volts, oil pres and water temp and hour meter. The generator is direct drive. The other ZXB powered gen sets I see always have a belt driven fan (zxb-3) - this one does not. I don't have a picture to post right now, but will try to get one. Thanks for any help!

[Rhino]

Cant you find any lable on it anywhere saying what output is? A picture might be what you need to get your answer. I have a zxa with a belt driven fan.

[Rich Mc]

Your genset is a PU-35/U. 2.5KW@120V60Hz and 2.5KW@120V400Hz.
Signal Corps Tech Manual is TM 11-975

[lockeowner]

Originally Posted by Rich Mc

Your genset is a PU-35/U. 2.5KW@120V60Hz and 2.5KW@120V400Hz.
Signal Corps Tech Manual is TM 11-975

Is it capable of putting out a total of 5 kw then? Or is the output split between the two sides for a total of only 2.5?

Thanks for the info! I'll try to dig up a manual. Also, any idea when there were built? This one has only 120 hours total on it (hour meter still works) and I had the head off years ago and indeed the valves and cylinders looked new.

[Rich Mc]

5 KW is the combined max output. The earliest reference material is 1944 and not mentioned in the same reference material in 1951.

[lockeowner]

Last question - where can I find a copy of the manual? TM 11-975
Is there a company that sells reprints? Anybody have a PDF?

[Rick Harvey]

ACTUALLY it is 2 different generators of 2.5 KW each, and they can NOT be hooked together. It would be like trying to hook a car going 60 to one going 400, so to speak.

You can use the 60 cycle / hertz on things with motors and are frequency sensitive. ( most everything you have)

You can use the 400 cycle / hertz for incondescent lights and element heaters (pure resistive loads).

400 is used on a lot of aircraft. I think one posting I seen the other day said a B-29? had one similar to that, for preheating.

[Brownboat]

Is the genset in the attached pic the same as what you have?

[Ed Stoller]

I have a Hobart PE-197 with the Hercules ZXB engine.

[Brownboat]

Do you have a pic of it?

[Ed Stoller]

It would be easier for me to send pictures off list. Send me an email and I can send pix off list. edstoller at earthlink dot net.