Hall Effect Sensor ID

[tjmurf]

Was hoping someone might assist with a part identification. The sensor appears to be an Allegro and a Hall Effect. I'm just not certain of the specs. to replace or change. It's to a wind speed sensor.

Any help would be appreciated!

Thanks!
TM

http://files.engineering.com/getfil...ac-90f5-9cd5c5aafe89&file=20171002_223811.jpg

http://files.engineering.com/getfil...ac-b81b-d793b60848a6&file=20171002_230945.jpg

 

[Skogsgurra]

From the Allegro page:

A1321, A1322, and A1323: Ratiometric Linear Hall Effect Sensor ICs for High-Temperature Operation (Product Details)

http://www.allegromicro.com/en/Prod...ICs/Linear-Position-Sensor-ICs/A1321-2-3.aspx

This device is no longer in production. The device should not be purchased for new design applications. Samples are no longer available. Date of status change: October 31, 2011. Recommended Substitutions: For existing customer transition, and for new customers or new applications, refer to the following parts: ...

The "..." doesn't seem promising. No replacement. I wonder why? Were they failure-prone? Do you have more than one that failed?

High temperature device, rather large dimensions. The dimensions point to a low-resolution application.

In such cases, I have used reed switches with a pull-up resistor. Sometimes with a 500 - 1000 microseconds debounce. You do not need more, most reed switches bounce in the order of <250 us. Sensitivity is not a problem. The designers of such machinery usually have safety margins (strong field) up to around ten times what is needed. If field is week, it can be 'helped' with positive bias from a permanent magnet. Or you can use a wound reed relay and add some bias to the winding. But that has, in my experience with different low speed applications never been necessary.

A thought: It may be that the magnetic field is weak? Have you tested with an external magnet? The reason for failure may not always be what you first think.

Do you have schematics? Would help a lot.



Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[VEBill]

Here's the picture inline for those following.

 

[VEBill]

"...wind speed sensor."

Is this for a one-off repair?

If so, then I'd be inclined to replace it with an approximate equivalent. Might need to compare specs, and perhaps rearrange the three pins into the right spots. There's a risk that this approach wouldn't work.

 

[Skogsgurra]

The little wind speed sensor sitting at the tail? SKF makes them. Perhaps better replace the whole thing. What does the wind-mill supplier say?

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[tjmurf]

One-off repair.......YES
The sensor/controller is connected into an outdoor splash pad / fountain. The display can be shut down automatically when the wind speed gets to high.

It would be nice to find the original spec sheet so I had something to compare to. Is it a switch or is it linear. Manufacture has not been that helpful.

Thanks for trying!

 

[VEBill]

The link provided by Gunnar answers all that. Assuming that marking "21E" is their A1321, then the A1321 datasheet is downloadable on that page. Righthand side of page.

 

[VEBill]

And checking the datasheet on Gunnar's link, the PN marking is exactly that. Last two digits plus a temperature code. So confirmed.

Hopefully you're all set. Good luck.