So, I have a DC marine water pump. It's typically rated for "12v" lead acid batteries, so it should be designed for around 13.5v. I am going to be pwming it and monitoring the current, with a base voltage of around 15.5v. Is this likely to significantly affect the lifespan of the motor?
1 Answer
If you are going to regulate the current using PWM, the voltage of the pulses will not make much difference in the range of 15% or even 30% above the rated DC average voltage at this voltage level. The important thing is not to overload the motor. If you were to increase the average voltage by 15%, that would increase the motor speed by 15%. To drive a centrifugal pump 15% above normal speed requires 32% above normal torque and 52% above normal power.