Why your pump needs a drive
Throttling a valve wastes power. Slowing the motor does not.
When to rewind and when to replace
Five questions to ask before you send a burnt motor back to work.
When a motor burns out, the first question is whether to rewind it or buy a new one. There is no single answer, but five questions help.
How big is it? Below about 5.5 kW, a new IE3 motor often costs little more than a good rewind. Above 30 kW, rewinding is almost always cheaper.
What is the core like? A motor that has run very hot may have damaged laminations. We test the core before quoting; if the losses are high, the rewound motor will run hot again.
How old is the design? A 25-year-old IE1 motor rewound is still an IE1 motor. If it runs most of the day, the power saved by a new IE3 motor may pay for itself.
Why did it fail? Single-phasing, overload, water and bearing failure cause most burnouts. Unless the cause is fixed, the next winding will fail too, whatever you choose.
How urgent is it? A stock motor can be on site the same day. A rewind takes 3–10 days. For critical machines, keep a spare motor and rewind the failed one at leisure.
