1. Home
  2. Electronics Design
  3. Slotted optical switch and Halls

Slotted optical switch and Halls

I've got some old designs that use the H22L2 slotted optical sensor. Used to be able to get them from Fairchild but they're now phased out. They now only have phototransistor versions and not the logic output types.

Closest substitutes I found are from Optek. Omron also has some good ones though in a different form factor. Does anybody have other recommendations?

On a related note, I've also got some Hall effect sensors used for limit switches with the magnet passing side to side across the sensor face. The repeatability is not as good as I would like it to be. Any suggestions on how to improve repeatability? Have been experimenting with a Micronas HAL506 which is high sensitivity, temperature compensated and a chopping amplifier type so I'm thinking that my problem is more in trying to concentrate the magnetic field. So far I've been using a 1/8" diameter AlNiCo rod magnet.

Tia - Oppie

Reply to
Oppie
Loading thread data ...

Is there no attempt to close the magnetic loop? That is to say, no attempt to decrease the air gap?

Reply to
Robert Baer

Running with a minimal air gap of .010" Was thinking of using a steel U channel under the sensor to further increase the sensitivity.

I probably should also get hold of a linear Hall to see if there are any other fields that might be biasing the switch. There is a step motor in the area and I don't know yet how much stray flux comes from it.

Trying to get away from using microswitches for the limits. The precision has been good, in the order of 50 uM. The Omron optical slot sensors are a bit larger and more expensive but also had a similar precision.

Reply to
Oppie

to

nly

s?

506

er

Extensive report:

formatting link

Precision: better accuracy. ISTR some experimenting with magnetic circuits too, somewhere deep in that thread.

HTH

-- Cheers, James Arthur

Reply to
dagmargoodboat

formatting link

Very nice reference. Thank you!

Reply to
Oppie

De nada. I see it wandered off track as online threads do--the useful engineering info's mostly up front.

-- Cheers, James Arthur

Reply to
dagmargoodboat

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.