weressl
Esteemed Member
steveng said:what does asd mean?
thanks
Adjustable Speed Drive, the official designation as per IEEE 1566
steveng said:what does asd mean?
thanks
weressl said:That is not exactly corect. The thermal protection model in the ASD software takes into consideration the speed and the load characteristcs. The thermistor is to protect against misapplication or rather to extend the motor application to conver all possible scenarios. I would say 95% of aplications could live without thermistors and it is an unnecessary expense. It is very useful in hazardous(classified) aplications, even though it is not required.
Jraef said:I don't disagree with that, but if you read those VFD manuals in detail you will likely see that the thermal protection modeling they preform is based on an assumption that you are using a motor rated for inverter applications. Such s not always the case; many people retrofit VFDs into older existing motors that were never designed to handle the excess heat created by the output harmonics and reduced cooling. Maybe not a great idea, but it happens all the time. There are also a lot of motor salesmen who, when confronted with an inverter application, seem to think the entire concept of inverter duty motor designs is a scam and not to be paid any attention. The problem is, they are usually not around when the motor later fails.
mdshunk said:Huh? I guessed it was probably a lack of cooling, you say that's nonsense. Then Jref brings it up and you say "exactly right". You're just mean.