60HZ / 50HZ shore power

What kind of equipment? Does it depend on back emf to contain the magic smoke?

Anything with an AC motor will run 20% slower and the motor will deliver 20% less HP, so will likely overload if trying to do the same amount of work. Pumps and fans might be OK, but will deliver less water or air, meaning they may need to run longer to accomplish a specific task and that may have consequences as well. Anything with resistive heating will draw more current, likely causing protective devices like fuses and circuit breaker to open. Anything with electronic power supplies will have a lower output voltage, probably affecting the electronic device it feeds and cause it to malfunction.

Other than that, no problems.

Anything with resistive heating will draw more current, likely causing protective devices like fuses and circuit breaker to open.

Ooh--ouch, check your Ohm's Law. With resistive load, half the voltage = 1/4 the wattage, amp draw goes way down here, resistive doesn't "care" about frequency.

Example 480 volts applied to a heater produces 4800 watts. Its effective resistance is 48Ω and its amp draw was 10. Now apply 360 volts. 360v / 48 Ω = 7.5 Amps and its new power is 2700 watts.

What Raymond is trying to do is not a good idea and should produce unsatisfactory results.

A client of mine just bought a German made 100 hp 4000 psi 4-stage (50 hz motor) air compressor. Its gone to "hell-in-a-handbasket" with 200 hrs on it, 3 blown stages and scored cylinders, moisture and "clinkers" in the oil due to over speed and excessive cylinder heating ... (the factory start-up rep measured 370 degrees F on the compressor heads even with circulating cooling tower water !) That's because they oversped it with applied 60 hz. power.

Moral to this epistle: experiments are costly!

Anything with resistive heating will draw more current, likely causing protective devices like fuses and circuit breaker to open.

Ooh--ouch, check your Ohm's Law. With resistive load, half the voltage = 1/4 the wattage, amp draw goes way down here, resistive doesn't "care" about frequency.

Opps, derr derr derr.

I'm so used to working on automated systems that would boost output to maintain heat, forgot about basic laws and limits. Can't increase the output beyond the input!

<Anything with electronic power supplies will have a lower <output voltage, probably affecting the electronic device it feeds <and cause it to malfunction.

Generaly, an electronic power supply will work for any world line voltage, 50/60 Hz, delivering the necessary dc voltage.

For motors, a variable frequency drive would drive any ac motor, from any voltage, mono - tri phase.

A transformers current is limited by resistance plus reactance, reactance doing most of the limiting. A 50 cycle transformer requires more iron to keep the reactance high enough to prevent excessive current and the resulting overheating.

Reducing the voltage helps, but is not predictable. Applying voltage to the device gradually until there is a non linear increase in current will usually determine the saturation point of your inductor beyond which the device will generate heat.

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The effect of the 50Hz, rather than 60Hz, is to raise the B value which may then move you onto the non-linear portion of the B-H curve where you get very much higher H, and thus more current. However, that can easily be offset by a corresponding decrease in voltage (Faraday's Law), and there is even a slight gain in doing it that way since core losses are somewhat frequency dependent.

Furst of all where jou find shore power 360vac and 480vac

I am from Europ and we have 390/400 vca 50HZ

when jou change 60HZ to 50HZ ther is no problem only the speed of the engin go down and the produktion is 20% les

Not quite accurate enough for me, some motors will run, but overheat and burnout on LESS voltage. Some motors may not even start and will just stall and overheat.

I have actually seen this happen when the equipment transformer, in spite of being correctly setup according to the manual, was actually one tap too low on output, if you checked the voltage produced.

After several motor replacements by other colleagues, I measured the O/P voltage and set it one tap higher, problem solved.....on the lower voltage the motor ran for up to one week before failing. The motor needed 220-230 volts and was actually getting 198 V AC...

If a motor receives a similar amount more (over) voltage, this does not usually cause any problems.....240-250 volts for example.....

Someone else has already mentioned this point earlier.....

Been there, done that and got the T-Shirt!!

From the maintenance workers point of view it sucks. The undervoltage causes the windings in motors to pull more amperage in an attempt to compensate. The increase in amperage overheats the wire causing the windings to short. Install a transformer and boost the voltage to match the circuit requirements.

Good luck,

James

It's not that simple unfortunately. The motors will saturate.

One thing is sure.....lot of savings.. if no effect on plant/ equipment out put.

Having been in the Navy and hooking up shore power to the ship, equipment designed for 60 Hz, if you run it at reduced voltage, will draw excessive current and burn up whatever it is you're planning to run it on. Some appliances and electronics come with a switch on it to select 50 or 60 hz. If it doesn't have that switch, it will run slower. The lower voltage will do damage though. what do you plan on running?

Well put!

The "what type of equipment" question is spot on. If you've got equipment that is using a AC / DC converter for equipment (GPS, radar, radios, etc.) then you have to check if the power supplies are rated for the input frequency and voltage. If not you might smoke the supplies. Either way the equipment won't work.

How many KVA do you need?

I had a rural customer with single phase power. He bought a machine with several small 3 phase motors. I installed a surplus VFD and ran it at a fixed 60 HZ output and correct voltage. The small motors started "across the line" no problem.

HOWEVER, MANY DEVICES DON"T LIKE THE PWM WAVE FROM A VFD!

You may want to consider a UPS type power supply that puts out sine waves and can handle the voltage and frequency input variation. Its only $!