Limit switch for actuator help

[StealthRT]

Hey all i have bought a actuator from firgelli auto and i need to add a limit switch for the down part.

**broken link removed**

That is a drawing from the company's website about how to hook up the limit switch. Now i have 2 problems with this drawing:

1) It does not tell me what type of switch to get
2) Wont this hinder the up part if the ground is cut off when it hits the lever?

They sell a kit with the limit switch(s) and other things but again they do not tell what type of limit switches they are.

https://www.firgelliauto.com/product_info.php?cPath=70&products_id=111

I plan on hooking the up/down to a relay (2 of them) that i control via a PC. They have a diagram for that as well

**broken link removed**

I emailed them and asked them if this would work with my own setup:

RELAY UP:
> Purple wire > C
> Grey wire > NC
> Blue wire > NO

> RELAY DOWN:
> Black wire > C
> Grey wire > NC
> Blue wire > NO

My relays look like so:

**broken link removed**

And this is a PDF of the relay:
https://denkovi.com/Documents/23-3.pdf

Any help would be great to (1) See what type of limit switch i need to buy and (2) Make sure my layout for the relay is correct.

Thanks!

David

 

[alec_t]

1) It does not tell me what type of switch to get

Any standard lever-actuated microswitch, with contacts rated at 15A 24VDC or better (based on the rating of the relays in the photo, and assuming those relays are suitable) should do. If the actuator is in a hostile environment then a sealed switch would be advisable.

2) Wont this hinder the up part if the ground is cut off when it hits the lever?

Yes. The actuator circuit shown has no provision for reversing the direction of travel.
If, however, the intention is to add components to reverse the power polarity, then the diode (if suitably rated to handle the actuator current) will provide a path to complete the circuit.

 

[panic mode]

this is what I would do:

you get your 3-pos momentary switch as control input.
there are two relays and two limit switches to handle actuator current and stop it at FWD or REV limit

 

[StealthRT]

this is what I would do:

you get your 3-pos momentary switch as control input.
there are two relays and two limit switches to handle actuator current and stop it at FWD or REV limit

Thanks for that, Panic Mode. However, i found a way to do it:
**broken link removed**

David

 

[panic mode]

you are welcome. i can't see your attachment but as long as it works, you should be fine. important thing about such circuit is ablity to back off from trip position. for example if you trip Forward limit. you must not be able to continue running forward but you also must be able to go back.

you can find limits switches at your local electrical supplier or online like
https://www.newark.com/limit-switches?isRedirect=true

usually you will want actuator to have roller lever or roller plunger but this will depend on your arrangement.

if your circuit is in dry and clean place and exposed terminals are ok, you can use low cost micro switch like
https://ca.mouser.com/ProductDetail...=sGAEpiMZZMumBvQ1hY/fBT/NxSgnZxL/dT3UNO0jdHs=

otherwise you will want sealed type like
https://ca.mouser.com/ProductDetail...=sGAEpiMZZMumBvQ1hY/fBTwmKTjlDqtwlA9XjJWYqAM=

note that last one has adjustable lever (with very large roller). most switches have small roller (5-15mm diameter) like
https://ca.mouser.com/ProductDetail...=sGAEpiMZZMumBvQ1hY/fBcorBE3BnrSX543jmganvf4=

Actuators can be AC or DC, often even those powered by AC have rectifier inside and use DC motor for higher torque so you need to know exact model.

 

[panic mode]

you can put it on PCB too:

 

[KeepItSimpleStupid]

You can do it with just two diodes and two limit switches.

 

[StealthRT]

Final

**broken link removed**

David

 

[StealthRT]

you can put it on PCB too:

Thank you for that layout Panic! I'll save that as i am sure it will come in handy one day.

David

 

[KeepItSimpleStupid]

The two limit/diode method. I hope you can understand w/o a picture.

Suppose you drew two Normally closed limit switches with a diode in series with each.
The diode "selects" the direction that the "limit" is valid.
Now put the two series combinations in parallel.
The above circuit goes in series with the actuator power.

 

[StealthRT]

Corrected the image

David

 

[StealthRT]

Final

**broken link removed**

David

Alright just got around to jooking this up and i started out with the "up" relay and hooked it up as stated in the diagram and nothing happens once i turn the relay on...

Any ideas as to why?

David

 

[panic mode]

i guess that version is not quite final then ;-)

if you energize relay on the left, motor will not run unless the switch is on (to bypass diode you inserted, because in this case diode is reversebiased).

 

[StealthRT]

i guess that version is not quite final then ;-)

if you energize relay on the left, motor will not run unless the switch is on (to bypass diode you inserted, because in this case diode is reversebiased).

I'm just trying out the UP relay for now. Haven't gotten to the limit switch yet. Needed to get this working first.

David