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Hi Everyone,
I'm hoping someone might be able to help answer a question which i have long pondered over. Firstly i am not an electrician, please dont hold it against me, i'm just interested to seek answers when there is something i dont quite understand.
I work in the event production industry and often have cause to run temporary electrical installs. There is nothing complex about this its just pluging leads and boxes together. We always use qualified electricians if ther is ever any hard wiring or high power requirements to check everything is safe.
My question relates to three phase power supply's. I have aksed many people this over the years and have never got a consitant answer.
It is common place to provided a 32amp three phase supply by a venue, from the mains or from a generator (im aware of power factors and will come to this later) Typically we would plug this supply straight into a 32amp three phase distribution box. On the other side of this box we would take 3 x 32amp single phase supplies. Further along these would be split into 2 x 16amp supplies and then ultimately at the end point a 13amp plug for the end user.
In order to identify what power supply we need to request on site we would normally start by working out how many amps we need. most of our equipment tends to be single phase. lets say it amounts to 12kw (50amps x 240v). We would ask the venue to either supply a 63amp single phase supply or a 32amp three phase supply.
My question is how many amps are available on a 32amp three phase supply, logic suggests upto 96 so we could draw a maximum of 32amps per phase. A total of 23.04kw. However i have been told that three phase power isnt that simple and not all the power is available, In addition we normally work out requirement using a voltage of 240 but i understand three phase to be 415v. I'm not sure what bearing this has on things.
I appreciate the answer to this question might be different if the supply is mains or generator.
I have been trying to use this calculator:
Electrical 3-phase and single phase power,current and energy calculator, free online - https://power-calculation.com/electrical-power-current-calculator-3-single-phase.php
but dont really understand how it works, i think the sqrt of 3 is involved somewhere. Seemingly when i put in a power factor of 0.8 and 415v it seems to suggest the active power equates to 18401w which means around 76.6 usable amps for our single phase appliances. Is this right or is it less that it should bedue to the power factor which i allowed for the generator? i'll be honest im stabbing around in the dark with this.
If anyone could shed any light on this i would be super grateful.
I'm hoping someone might be able to help answer a question which i have long pondered over. Firstly i am not an electrician, please dont hold it against me, i'm just interested to seek answers when there is something i dont quite understand.
I work in the event production industry and often have cause to run temporary electrical installs. There is nothing complex about this its just pluging leads and boxes together. We always use qualified electricians if ther is ever any hard wiring or high power requirements to check everything is safe.
My question relates to three phase power supply's. I have aksed many people this over the years and have never got a consitant answer.
It is common place to provided a 32amp three phase supply by a venue, from the mains or from a generator (im aware of power factors and will come to this later) Typically we would plug this supply straight into a 32amp three phase distribution box. On the other side of this box we would take 3 x 32amp single phase supplies. Further along these would be split into 2 x 16amp supplies and then ultimately at the end point a 13amp plug for the end user.
In order to identify what power supply we need to request on site we would normally start by working out how many amps we need. most of our equipment tends to be single phase. lets say it amounts to 12kw (50amps x 240v). We would ask the venue to either supply a 63amp single phase supply or a 32amp three phase supply.
My question is how many amps are available on a 32amp three phase supply, logic suggests upto 96 so we could draw a maximum of 32amps per phase. A total of 23.04kw. However i have been told that three phase power isnt that simple and not all the power is available, In addition we normally work out requirement using a voltage of 240 but i understand three phase to be 415v. I'm not sure what bearing this has on things.
I appreciate the answer to this question might be different if the supply is mains or generator.
I have been trying to use this calculator:
Electrical 3-phase and single phase power,current and energy calculator, free online - https://power-calculation.com/electrical-power-current-calculator-3-single-phase.php
but dont really understand how it works, i think the sqrt of 3 is involved somewhere. Seemingly when i put in a power factor of 0.8 and 415v it seems to suggest the active power equates to 18401w which means around 76.6 usable amps for our single phase appliances. Is this right or is it less that it should bedue to the power factor which i allowed for the generator? i'll be honest im stabbing around in the dark with this.
If anyone could shed any light on this i would be super grateful.