Electric motor

i installed an electric single phase cutting machine at the end of a 2.5mm cable that is about 500 meters long but the motor speed is very low...so therefore wont let the machine cut properly... i need a way to solve the problem without changing the cable used already.

Hi,

I think what you need is an current amplifier or sort off that does the job. Just like those used on transmission lines. That is when you don't want to change the cables you already have. But the best way really I think is a proper cabling.

thank you, pls what sort of amplifier are u talking about.... can i connect the machine to a control box with 16uf capacity inside the box?

Chukwu

It sounds like distance is causing a voltage drop and you need a boost transformer to bring it back up to 120 or 240V. Something similar to an 85-M030 that Dongan makes. You would need to calculate the KVA rating that you'll need and measure the voltage at the end of the cable to determine how to wire it up (Buck-Boost transformers are wired differently depending on how much bucking or boosting is needed).

If you could switch to a three-phase motor and use a VFD to control the motor speed, a VFD might have enough input voltage tolerance to ignore the voltage drop.

THANKS @ PICK..............HELPFUL

Cable is very lenghty due to which there is voltage drop in that cable and hence less voltage is being fed to your cutting machine resulting very low speed. shorten the cable length to suit your working place. this will solve your problem.

Obviously the long cable (500meter) caused significant voltage drop so that the cutting machine can't work properly.

I believe that there is nothing much you can do if you insist no change for the cable, in other words, you don't use a thicker cable.

But there is still one way which should solve the problem without changing the cable, just learn from the electric company, namely high voltage low current to convey electrical power over a long transmission line.

Just use a step-up transformer to raise the voltage at the source end of the cable and then use a step-down transformer to lower the voltage at the load end., you may treat this as a joke, ...haha