brockbone
Member
- Location
- Glendale, CA
Any body know if it is a bad thing to use a incandescent indicator lamp ( low amperage) on a 120 volt 400Hz system if it was originally designed for 120 volt 60 Hz?
120 volt 400Hz
- Thread starter brockbone
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drcampbell
Senior Member
- Location
- The Motor City, Michigan USA
- Occupation
- Registered Professional Engineer
Incandescent lamps are unaffected by different frequencies.
(until the frequency gets SO high -- many megahertz -- that radio-frequency effects take hold)
Likewise neon lamps, LEDs and fluorescent lamps with electronic ballasts.
Magnetic ballasts will probably behave badly.
(until the frequency gets SO high -- many megahertz -- that radio-frequency effects take hold)
Likewise neon lamps, LEDs and fluorescent lamps with electronic ballasts.
Magnetic ballasts will probably behave badly.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
No problem.
synchro
Senior Member
- Location
- Chicago, IL
- Occupation
- EE
Should be no problem electrically. There's a small but finite chance that the 60Hz bulb could have a mechanical resonance near 400Hz that could produce an audible tone.
It will last longer...
drcampbell
Senior Member
- Location
- The Motor City, Michigan USA
- Occupation
- Registered Professional Engineer
If that's true, it's not due to the higher frequency.
The 400-Hz systems I've seen tended to be lower voltages, either 200Y115 or 190Y110.
(full disclosure: I haven't seen one in a while and that's likely to be obsolete information)
PaulMmn
Senior Member
- Location
- Union, KY, USA
- Occupation
- EIT - Engineer in Training, Lafayette College
Isn't 400 Hz usually aircraft??
hbiss
EC, Westchester, New York NEC: 2014
- Location
- Hawthorne, New York NEC: 2014
- Occupation
- EC
I haven't seen it, but I understand that a tool and die place here uses 400Hz handheld grinders because they can be made really small.
-Hal
-Hal
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
Actually 400Hz is not uncommon in locations where they want small/lightweight motors and other electromagnetic devices, as Hal mentioned.
However I don't believe I have ever heard of an application at only 120V, although I want to say it might occur on ships.
I don’t really know how true it is..
I was alluding to the impedance of a wound coil inductor being affected by frequency.
less amps, longer life before filament burns out...
I could be wrong..
ptonsparky
Tom
- Occupation
- EC - retired
A factory that has since moved away used to have high frequency grinders but i haven’t seen any since they left 30 years ago. Give or take a half decade.
GeorgeB
ElectroHydraulics engineer (retired)
- Location
- Greenville SC
- Occupation
- Retired
A plant where I used to work had 400Hz MG sets with 2 pole motors directly turning routing bit for wood shaping. I don't know if the motor rotors were special, but the rotors were better balanced than off-the-shelf.
drcampbell
Senior Member
- Location
- The Motor City, Michigan USA
- Occupation
- Registered Professional Engineer
So ... the air-core inductor created by the dozens (?) of turns of a curly-cue filament has a significant impedance at 400 Hz?
Never said significant, now did I...
I haven't come across them on the ships I've been on but that's mainly been ice breakers. Actually, on one of them, the propulsion system was 100,000 hp cycloconverter with a max speed of 20Hz.
A division of our company made drives and motors that ran up to 30,000 rpm. Small for the rated power. And thus, low inertia. From 10,000 rpm to standstill in half a second and one degree of position. The application was machine tools in an aircraft works. The performance was critical in terms of productivity. The stop/start for a tool change had to be as short as possible.
ptonsparky
Tom
- Occupation
- EC - retired
Were any of the drives you worked with ‘in stock‘ items ready for shipment upon order?
Some, for standard applications, were. The drives we put on the ice breakers were designed and built from component level.
The high speed drives were all custom built.
Not sure if that answers your question........
winnie
Senior Member
- Location
- Springfield, MA, USA
- Occupation
- Electric motor research
I just set up an aircraft ground power unit for our lab. The output is 400Hz 200/115 wye.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
In addition to motors being lighter, the generators/alternators connected to the aircraft engines are also much lighter at 400Hz. But you need either high pole numbers or high shaft speed.
winnie
Senior Member
- Location
- Springfield, MA, USA
- Occupation
- Electric motor research
High shaft speed is generally not a problem for turbine engines. Speed regulation however is; you don't want your main engine speed set by what the alternator needs to get 400 Hz. Apparently some aircraft use 'wild frequency' for loads such as heaters that don't care about specific frequency (the lamp that opened this thread) and there is a move afoot to over-all wild frequency power.
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