Large motor starting
Large motor starting
(OP)
I am running SKim.M y question is, what we need to run by SKIM in order to determine if the motor can start properly.
Thank you in advance.
Thank you in advance.
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RE: Large motor starting
The torque requirements to accelerate the load will dictate if reduced or full voltages are required.
The accelerating or starting time in seconds will be:
t= WK^2 x (Drpm)/(308 X Tave)
Drpm = speed change
Tave = Average motor torque minus load torque (Lb*Ft)
Note that at reduced voltage the motor torque is reduced with the squared power of the voltage reduction ratio.
RE: Large motor starting
RE: Large motor starting
Just a plug for an excellent product...
We use SKM as our primary modeling tool for predicting RV starting success. In nearly all applications where we have run a simulation, it has been dead on correct! On 3 occasions, competitors claimed to be able to do something that we said couldn't be done because the SKM models did not bear out, and that turned out to be true (and costly for the competitors and end users).
The only minor drawback is in modeling solid state soft starting, because it can only model a fixed current acceleration, not a true ramped acceleration. But to be honest, I cannot see how any PC based sofware program could model all the variable dynamics of ramping the voltage or current, so IMHO it is as good as is reasonably possible.
"Venditori de oleum-vipera non vigere excordis populi"
RE: Large motor starting
What is the DRPM ?
Bob
RE: Large motor starting