Hmmmm... 30 HP is a lot.
1 HP is 746 Watts and I usually use 750 to round-up the numbers. Also, Watts (power) is equal to Voltage x Amps.
30 x 750 = 22,500 Watts
22,500 = 240 x Amps; therefore, Amps = 93.75. ... That's a lot of current and for reference is about 2.5 times as much as a central air conditioning unit in a typical 3 bedroom house. 1 Watt is equal to 3.4 BTU so, that's the equivalent of a 76,500 BTU heating or cooling device.
Those Amps are when the motor is pulling the full 30 HP -which hopefully doesn't happen all that often.
Anyhow, under full load the power from the meter going into the RPC will be at least this much plus any inefficiencies from the PRC itself. The best quality motors are about 95% efficient and typical values range anywhere from 75 to 85%. I would roughly estimate a 10-15% loss in the RPC so, the actual power coming out of the meter is right around 100 Amps (give/take a little).
The startup current on a motor can be quite high -especially if there's a load. An unloaded motor has a very brief draw of about 1.5 x the rated current and something like a compressor motor (which usually has a high load) can be upward of 3 to 4 times the rated current...
In your shoes, yes, I'd get a dedicated panel box for this and depending on how much you load the machine, you may need to look into "slow-blow" type breakers or possibly a VFD to use as a "slow-start" device if at all possible.
Ray