What KVA Transformer do I need for 35 antminer s9?

[balde13]

Hello,

I have a mining farm of 35 antminer s9, but I am currently in the phase of getting a KVA transformer. The electrical contractor previously bought a 112 3-Phase 120V KVA transformer, but he says that if I plan to expand in the future (50-60 miners) I would need a 150 or 225 KVA transformer. He also told me that the 112 KVA transfomer can only take about 30 miners, so I am not really sure what is the true value of miners that the 112 KVA can take.

Thank you.

[1715481241]

1715481241

[1715481241]

1715481241

[NotFuzzyWarm]

a 112 3-Phase 120V KVA transformer

You mean a 120V 3-phase 112kVA transformer?
For a start - whenever possible supply 208-240V to the PSU's. Less current draw means thinner wire can be used (cheaper) plus it is marginally more efficient.

kVA vs actual KW depends on the power factor of the PSU's but a good rule of thumb would be KW = kVA*0.9 (modern PSU's are power corrected to give 0.9 to 0.95PF). Typical wall plug power draw for an s9 is between 1,250w to over 1,300w depending on the model and ambient temp.

[banman24]

https://www.rapidtables.com/calc/electric/kw-to-kva-calculator.html

Use this, if your current transformer is 112KVA you should be ok to practically double the amount of machines you have.