Nice inexpensive optical encoder found

I’ve spent several months looking for nice industrial grade quality rotory optical encoders on E-bay but just not found anything at nice hobby prices avalible. Finally I stumbled upon B&G micro and they seemed to have a nice price on one without a lot of details provided. I went ahead and ordered two and they arrived today.

They are marked made by OAK/Grigsby, part # 91Q128-43-00410. I assume this means 128 steps per rev.

It has kind of a useless 4 pin connector on the end of the 5 inch 4 conductor solid wire flat cable. I just lopped off the connector and soldered the bare wire ends to a 4 pin header. I placed ground on pin 1 (marked with a stripe) and +5vdc on pin 4. Channel A & B are pins 3 & 2 respectively. I put my two channel scope on pins 2 & 3 and could see very nice quadurture square waves being generated as I turned the knob in either direction. Being optical there should be no contact bouncing like with mechanical encoders and the pules seemed nice and square to me.

The encoder has a nice feel with a solid drag and no detents, feels just like a quality hi-fi volume control feels. The body is 1" square and about 1/2" thick. It uses standard 1/4" knobs, so that is nice.

All in all this is quite the steal for $5 each (or $4 if 4 or more) in my opinion and as I said I’ve been looking for quite a while. Now I need to decide if owning just two is enough. :wink:

Lefty

OPPS, forgot the link: http://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=12916

Why do you think it's optical?

Why do you think it's optical?

By researching via goggle of course. Seems Oak/Grigsby was acquired by Electroswitch at some time but they still list a spec sheet for the 90 series optical encoders:

http://www.electro-nc.com/products/900index.shtml

http://www.electro-nc.com/oak/p0104.pdf

Mouser seems to list a similar 90 Vs 91 model for $51 each.

http://www.mouser.com/Search/ProductDetail.aspx?qs=XvXsANjzvCOSitFFQ9IuOQ%3D%3D

By wiring channels a & b to interrupts 0 & 1, I was able to get 128, 256 and 512 steps per revolution depending on if I activated both interrupts or just one, and/or if I set to interrupt on change or falling state.

Lefty

Nice catch, Lefty!

Thanks for sharing it: I just bought from BG last month, but missed those encoders because I wasn't shopping for motors.

Of course, you've now put me in the same pickle of deciding whether two is enough, but I'll forgive you since you turned me on to a source for something I didn't think I could afford ;D

btw, I've been buying from BG for about 30 years, and last month's order was my first disappointment: the 2.1mm panel-mount power jacks I got for a buck are not as nice as the ones I paid $2 for at All Electronics. They have a solid center pin instead of the split springy one in the more expensive jacks, and I've had a problem with one power plug not making reliable connections. And the finish on the panel nut is really rough and cheap-looking. But that's part of the adventure of buying surplus, and I highly recommend BG because of the number of extraordinary deals on really neat stuff I've gotten from them over the years.

Ran

Is this just for turning by hand, or is there a way to connect it inline with a motor that is not clear from the picture? ...I guess you could connect it to the far end of the shaft with the gears, etc in the middle?

Is this just for turning by hand, or is there a way to connect it inline with a motor that is not clear from the picture? ...I guess you could connect it to the far end of the shaft with the gears, etc in the middle?

You would have to couple it to a shaft end or else possibly mount a gear to it and gear drive it. Spec sheet for this model is good up to 300 rpm due to it's bearing construction.

Just finished a proof of concept sketch, modifing some encoder sketch I found on this site. Using four pins and including both interrupt pins 2&3, I was able to process both encoders sending position data to the IDE serial monitor. They work real well.

Lefty