Square D selector switches

[ches2443]

In the Square D catalog, there is a chart that shows how to match the cams whith the Ka1, ka2, and ka3s contractors. To get the on and off selecting that you need. This part I understand. What I don't understand is where the ka4, ka5 and ka6s come to play. The chart doesn't show them. And the only mention the catalog gives is that they open and close early. To look at them; the contact are a little larger then 1-3s. So what are the ka4, 5, and 6 used for.

 

[jim dungar]

You can use a combination of an 'early make' and a 'late break' to create overlapping contacts. If your switch was Off-Hand-Auto, overlapping contacts would allow you to switch between the Hand and Auto positions without any contact opening.

 

[ches2443]

I think I get it

I think I get it

You can use a combination of an 'early make' and a 'late break' to create overlapping contacts. If your switch was Off-Hand-Auto, overlapping contacts would allow you to switch between the Hand and Auto positions without any contact opening.

Thanks: I thick I understand. The 4-6s makes shore that you don't lose one contaction on one contact before making the second contaction on the second contact. Does that sound right?

 

[jim dungar]

Thanks: I thick I understand. The 4-6s makes shore that you don't lose one contaction on one contact before making the second contaction on the second contact. Does that sound right?

I am not familiar with the term contaction (I would have used continuity), but I think you have the idea.

 

[LarryFine]

Methinks the term you're looking for is make-before-break.

 

[glene77is]

Methinks the term you're looking for is make-before-break.

Larry,

Yes, that is also called a "non-jogging-switch-over".