contactor question

[Thirst4Knowledge]

When you read a contactor and it says 40amp resistive does that mean continuous? And what about a load with harmonics, like a lot of ballasts, what would that do to the rating?

 

[Volta]

When you read a contactor and it says 40amp resistive does that mean continuous? And what about a load with harmonics, like a lot of ballasts, what would that do to the rating?

I have seen contactors with 50a resistive, 40 a FLA ratings. Less inductive current allowed.

I don't think that you need to limit a continuous load to 80% of the contactor rating, though I would limit an inductive load to 80% of the resistive rating.

 

[LarryFine]

When you read a contactor and it says 40amp resistive does that mean continuous?

Yes, because opening under load is much harder on contacts than continuous current.

And what about a load with harmonics, like a lot of ballasts, what would that do to the rating?

Use the inductive rating.

 

[aaatraker]

Here is a link that should answer all your contactor questions.
Hope it helps.

www.automationmedia.com/Port1050\SiemensFreeCourses\cc_3.pdf
Kurt

 

[Thirst4Knowledge]

Here is a link that should answer all your contactor questions.
Hope it helps.

www.automationmedia.com/Port1050\SiemensFreeCourses\cc_3.pdf
Kurt

Thanks you