I'm playin devils advocate
 

Okay theres another thread in the forums that asks about running your pump 24/7, well in a post by BB2K he links to this article ( http://www.procooling.com/articles/h..._pumps_-_p.php ) in which the author writes that using a relay is bad and will shorten the life of your pump.

What I want to know is what is your experience with this? How much does it shorten the life of your pump? Will I need to replace my Danner Mag3 every couple of months? Will I lose 3 weeks off of it's total life? Whats the deal? I turn my computer off and on once a day so the comments in this article has made me wonder. Any other comments on turning the pump on and off would also be appreciated.

I might expect this kind of reasoning from a DC motor though...but here it goes.


The reasoning behind what he speaks of is that when you turn on the pump(Motor) reguardless if its a relay or not.. you send power through the fields to a non moving commutator...its like a split second dead short..until it starts to turn.


"Not to worry", unless you are trying to pump a fluid that would initially cause the motor to bog down or overload or basically cause drag of some kind. ie...pumping sludge.





Tuff

But also remember..... it's not the dead short, that will damage the motor! It's the heat normally associated with a dead short, that will burn the windings, resulting in the degradation of the very thin insulating film on the copper wire. That is what causes an electric motor to die.

I've used a pretty wide variety of centrifical pumps over the years and I've yet to see one fail pre-maturely from powercycling (infact I've only had one pump fail from motor failure, and that one was on 24/7)

I have test pumps that get power cycled very frequently at times, none have let me down.

I've never had a pump fail from motor failure in my pc water cooling, and they get power cycled every day, including my iwaki pump, I'ts not something I worry about.