Help with Limit switch recommendation

[martinbatts]

Help.
I used some cheap Amazon switches, and they kept flickering between open and closed.
So I bought some "better ones" and they are doing the same.
I even jogged by axis a few inches away from the limit switch, and it still flickered.
So.. I'm Dutch, meaning I'm frugal.
These switches are ~ $14 for six. NC
Work when I manually trip them.
But when i install them, and jog to trip them, after awhile, the switches flicker between tripped and cleared.
And then when I move away from the trip location, the flickering continues.

So..
Can anyone recommend a limit switch that isn't really $$ and works?

Thanks

[ShawnM]

Could you be more specific and tell us or show us a pic of what you have now so someone doesn't recommend the sane thing? Have you tried shielded wire on them? Do you have any errors in your error log from noise? Post a current report so we can have a look. You have heard that you get what you pay for, yes?

[cnckeith]

sounds like you have a wiring issue.

these el cheapos work fine for most applications. https://amzn.to/3UvcG4I

https://amzn.to/42wGOPk

[tblough]

I have never had a problem with Euchner limit switches. They've been used on machine tools for 90 years because they just work.

Https://www.euchner-usa.com/en-us/produ ... -switches/

I also think Omron makes comparable units. Cheap Chinese stuff is false economy.

[martinbatts]

Thanks for the response.
I am constrained.
I am using Stepper online Stepper motors and controllers and Centroid recommends using the DB-25 5V connections for that and I do. It works well. Centroid also says "do not mix the 24V inputs with the 5V DB-25 inputs. And the switch you mention looks like it would require me to use 24V

[centroid467]

Thanks for the response.
I am constrained.
I am using Stepper online Stepper motors and controllers and Centroid recommends using the DB-25 5V connections for that and I do. It works well. Centroid also says "do not mix the 24V inputs with the 5V DB-25 inputs. And the switch you mention looks like it would require me to use 24V

Well, we don't want you to wire 24V things to the DB-25 header. You can use the H1 and H4 inputs for anything that requires 24V inputs. That's how everyone installs their limit switches and that's how we designed it to be.

[ShawnM]

Thanks for the response.
I am constrained.
I am using Stepper online Stepper motors and controllers and Centroid recommends using the DB-25 5V connections for that and I do. It works well. Centroid also says "do not mix the 24V inputs with the 5V DB-25 inputs. And the switch you mention looks like it would require me to use 24V

You are confusing INPUTS and OUTPUTS on the Acorn board.

The stepper drives require 5v from a power supply to the PUL+ and DIR+ on the drives and the PUL- and DIR- go to the DB25 for signal to move. The DB25 signal to the drives is an OUTPUT from Acorn.

The DB25 has nothing to do with the +24v power going to the proximity switches. Power the proximity switches with a 24v power supply and wire the output of those switches to the Acorn inputs on H4 or H1. Those are INPUTS to the Acorn board.

You can use the Acorn dual power supply for this or add additional 5v or 24v power supplies to power any ancillary devices. If you add in any other power supplies in addition to the Acorn power supply you need to tie all the grounds or commons together between all the power supplies.

[cncsnw]

PLC inputs INP1 - INP4 are duplicated on the DB25 in addition to H4.

You can wire devices to either H4 or the DB25, and they will work in the PLC.

I believe they are electronically isolated from each other, and in both cases your switches just provide closure to COM so they don't really care about the voltage, but it would be unproductive to try to wire devices to the same input in both places.

Presumably if you wired a switch to INP2 on the DB25, and wired another switch to INP2 on H4, the behavior would be unpredictable.

I am guessing that was the point of the "do not mix..." warning that Martin was concerned over.

[ShawnM]

My bad, I thought he was talking about the stepper drives and the prox switches, the reason for my "inputs and outputs" statement. I didn't understand he wanted to wire the prox switches to the DB25.

[martinbatts]

PLC inputs INP1 - INP4 are duplicated on the DB25 in addition to H4.

You can wire devices to either H4 or the DB25, and they will work in the PLC.

I believe they are electronically isolated from each other, and in both cases your switches just provide closure to COM so they don't really care about the voltage, but it would be unproductive to try to wire devices to the same input in both places.

Presumably if you wired a switch to INP2 on the DB25, and wired another switch to INP2 on H4, the behavior would be unpredictable.

I am guessing that was the point of the "do not mix..." warning that Martin was concerned over.

Thanks. The Centroid documentation clearly and loudly states that one should not mix them.
So here's the thing. The power supply Centroid gave me is/was faulty (it only output 21.6V)
I bought a new one on Amazon ,(Centroid not responding) hoping that would fix it. It didn't.
btw my Acorn board is showing only 4.9V when tripped. I fear that is the source of my issue of the switches doing a trip/clear dance.
I talked with my son (who is also an engineer) and told him I'd try to use the 24V connections on the H2 connectors and lo and behold it works. But the Centroid warning has me worried. I have Stepper online Stepper controllers (DM860T which are dual 5V or 24V) and I'm contemplating using the 24V H2 and H3 Step & Direction connections even though the Centroid documentation says those are for Servo motors.
Any comment on that?