Some 7i76E questions

Im getting my limit switrches setup here and saw this line in the 7i76e manual:

"It is suggested that inputs like limit switches use normally closed switches with one
switch leg connected to field power and the other to the 7I76E input pin, so the normal
machine state (not at limits) is to have the inputs activated. This way, a open switch wire
or wire shorted to ground will cause a detectable machine fault. "

Obviously there is not enough space on feild I/O to connect 2 Limit switches and one home per axis. Should I just use one terminal and distribute from that?

Also running 24v with my sourcing inputs have any issues that require something special like pull up resistors.

Thanks,

Hi
you normaly got a Case Cabinat that holds the clamp blocks witch got lots of clams on 24V
like


or like here as well

In my eyes the detailed capture of each limit switch makes only sense when you can not see the axis. Problem is that it is sometimes not easy to dasychain electronic switches. But you can to chain at least two NC sourcing ones by having vcc supplied by the signal of the first. That should work for 24v and your 7i76e. Maybe even with 4. Worth a tried if you are low with signals.
m5c
Mike

Type_Zero_Design wrote: Im getting my limit switrches setup here and saw this line in the 7i76e manual:

"It is suggested that inputs like limit switches use normally closed switches with one
switch leg connected to field power and the other to the 7I76E input pin, so the normal
machine state (not at limits) is to have the inputs activated. This way, a open switch wire
or wire shorted to ground will cause a detectable machine fault. "

Obviously there is not enough space on feild I/O to connect 2 Limit switches and one home per axis. Should I just use one terminal and distribute from that?

Also running 24v with my sourcing inputs have any issues that require something special like pull up resistors.

Thanks,

Two limit switches for X, two limit switches for Y and one for Z(upper). Share limit switch and home. That's 3 inputs needed. Connect max and min in series Normally closed. So you always have input when not on limit, that way if wire breaks you will know.

it is the same principal as here
the cherry can take 24V easy so no need to change coltige

Hey guys,

Thanks for the info. Just to be clear I'm not asking about the inputs, I have plenty right now.

I was wondering about the feild power output and whether I should do something like pl7i92 suggested, and if that was going to cause any isses