Power Supply

[bavuman]

Hi, I need to know what can I do to Supply 440V 60Hz electrical equipment on 380V 50hz system.

 

[Skogsgurra]

Depends what kind of equipment it is.

Asynchronous (and synchronous) motors will run with near nominal torque but at a 17% lower speed.

Incandescent lamps will not light as bright as they will on 440 V. A big difference, actually.

Led lamps will work well.

Resistive heaters and boilers will deliver around 25% less power.

Switching power supplies will probably work as usual.

Linear power supplies will run cooler and, perhaps, show unacceptable ripple in their output.

Transformers will work as usual, perhaps with a somewhat elevated temperature.

Triacs and thyristors may or may not work. Digitally controlled ones will probably work fine.

Electromechanical clocks and timers will be around 16% slower.

So, what you need to do depends a lot on what kind of equipment it is.

What kind of equipment is it?

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[bavuman]

The hydraulic power unit (HPU) is electrically powered by a 15kW, 440V, 60Hz electric-motor
and is fitted with a 630 litre tank. The HPU is a simple unit with a fixed displacement gear pump
and is geared to pump at a set flow rate of about 30 litres per minute when the control valve is
fully opened. If the lever is partially opened then the HPU will direct a certain amount of the
flow through a relief valve which will cause a generation of heat in the hydraulic oil.
The HPU is fitted with a pressure gauge and an adjustable relief valve which enables the operator
to adjust the pressure that is supplied to the hydraulic motors and hence to limit the maximum
pull that will be exerted by the winch when it is doing the pulling (clearly this force can be
exceeded if the SWR is being pulled by an external force).

Please see attached Document as well.

Regards

 

[Skogsgurra]

OK, it looks like there is nothing but the 15 kW motor that is electric. And, since 440/60 is 7.3 V/Hz and 380/50 is 7.6 V/Hz it means that you are safe with regard to the motor's operation. But you will not get the same performance speed-wise as a 440 V 60 Hz motor voltage would give.

Run a test. If everything works satisfactorily, then keep it as is. If performance is marginal, then install an autotransformer (to increase voltage) and also a VFD (to rise frequency). But if you can accept the somewhat lower speed you are just fine.

One advantage with the 50 Hz operation is that the heat build-up will be less than with 60 Hz.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[bavuman]

Thanks and Much appreciated with your response. I will have to do some test when this equipment comes onboard.