Voltage spikes on motor startup

[740GLE]

Large change in current is commonly called inrush.

Spikes are commonly referred for large change in voltage.

At least that’s how I use the terms, each person can use their own preference.

 

[740GLE]

It shouldn't matter.
Amperage is constant throughout the circuit.

Actually the motor will draw more current if the voltage drop is large enough due to long runs.

Motors want to run at a certain RPM and fixed output, and if the voltage drops, the current will increase to balance out to a fixed output.

 

[timselectric]

Actually the motor will draw more current if the voltage drop is large enough due to long runs.

Motors want to run at a certain RPM and fixed output, and if the voltage drops, the current will increase to balance out to a fixed output.

Yes
But that same amperage is constant throughout the circuit. No matter where it's measured.

 

[Farm Boy]

I am not sure if it would work on your compressor or not, but there are some fairly sophisticated motor controllers that ramp up the rpm slowly vs going right to full blast.

Sometimes they are called variable speed drives / variable frequency drives but there might be another name.

You do need to be careful to not run the motor at too low of rpm for a long time as they depend on the fan rpm to cool.

The price of these has been coming down a lot over the past 20 years.

I looked into that. VFD's are speed control with in a motor rpm which is related and could replace a soft start depending on the objective application. But from the info I found a soft start would be better inline with an air compressor.