JohnXKennedy
Plastic
- Joined
- Jun 6, 2017
Hey everyone, I know this is a bit of a contentious subject but having searched a bit it seems there are different opinions floating around about what the true phase converter sizing requirements are for our lathes. I am attempting to find a RPC to run a qt15 which is 15hp continuous or 20hp 30 minute rated. So:
-Conventional wisdom says double your spindle HP for RPC sizing, does that mean 30hp (2x15) or 40ph (2x20) in this case?
-The manual recommends some very high amperage requirements (see last post of this thread LINK) Which is probably the right thing to do, but it seems unlikely everyone is actually running 60hp RPCs with 2/0 AWG drops to run their 15hp lathes...
-Who here is running QT15/20s etc with a RPC, which size did you go with? I see reports of VFD damage when the machine is starved for amperage
-Some here recommend decreasing accel times (fine by me), how much does this lower the amperage requirements? Enough to allow use of a smaller RPC?
-I will never fully load this lathe, but on the off chance it happens by accident I don't want to fry anything. Does anyone know if this is likely to happen if I have a converter sized to normal use but it suddenly overdraws under an extreme load?
Thank you all for any experience / information you can share on this subject.
-Conventional wisdom says double your spindle HP for RPC sizing, does that mean 30hp (2x15) or 40ph (2x20) in this case?
-The manual recommends some very high amperage requirements (see last post of this thread LINK) Which is probably the right thing to do, but it seems unlikely everyone is actually running 60hp RPCs with 2/0 AWG drops to run their 15hp lathes...
-Who here is running QT15/20s etc with a RPC, which size did you go with? I see reports of VFD damage when the machine is starved for amperage
-Some here recommend decreasing accel times (fine by me), how much does this lower the amperage requirements? Enough to allow use of a smaller RPC?
-I will never fully load this lathe, but on the off chance it happens by accident I don't want to fry anything. Does anyone know if this is likely to happen if I have a converter sized to normal use but it suddenly overdraws under an extreme load?
Thank you all for any experience / information you can share on this subject.