How to find a replacement hall sensor for unknown brand

[Monkeyleg]

I have some projects I'm working on, repairing some camera gimbal motors. One of the most frequent parts to break is the hall effect sensor in the 3-phase motor, as the gimbals get quite a jolt if the quad copter carrying the gimbal crashes.

I've been trying to find replacement hall sensors, but have had no luck. At first I thought they were Allegro sensors, but there's the number "1425" on the top, and it's a three-pin sensor. Allegro said it's not one of theirs. I've looked at scores of other sensor manufacturer sites, and nobody has a 1425. It's probably Chinese, as the maker of the copter is in China.

I figure my best bet is to find a sensor that's as close as possible in spec's to the existing ones.

Is there a way for me to determine what specifications I need for the sensors by measuring the existing working sensors? Is there anything I need to know other than the voltage being sent to the sensors and the voltage coming out of them?

Thanks for any replies.

 

[Colin Mitchell]

Why don't you start by trying different ones or buying another copter for spares.

 

[Monkeyleg]

I would try different ones, but there's thousands of them out there. I need to narrow it down, but I don't know how.

I'm buying the broken gimbals from crashed copters, replacing parts, and then selling them. So many of the gimbal motors are bad because of the damaged hall sensors that the best way to do the job would be to replace any that test bad. I'm tossing out motors that could be repaired if I knew where to get the sensors.

If I look on Mouser.com, I see filters for brand, type of mounting, type of sensor (linear, etc), supply voltage, supply current, gauss, temperature, and more. That's a lot of factors for someone like me.

I can measure the supply voltage. I can measure the output voltage, and maybe the current. I don't know how to measure the other variables, though.

I wonder if there's a circuit repair service that could measure a good sensor and tell me what the values are for all of the variables?

 

[Colin Mitchell]

Here's the Hall Effect you need 10 cents each

10pcs New Hall Effect Sensor A3144 A3144E OH3144E TO-92S

• $0.99
• 
  
• Free international shipping

 

[Monkeyleg]

That's not it. The ones in the gimbal motors are three-pin surface mount. Like this:

 

[Colin Mitchell]

Just cut the leads of the 10c Hall Effect and solder it to the lands

 

[Monkeyleg]

So the input voltage and current, output voltage and current, gauss, and other variables don't matter? Why would Allegro, Honeywell, Texas Instruments and other manufacturers make so many variations of the same three-pin design?

 

[Colin Mitchell]

Because they produce one type and get dozens of failures which they give secondary names to.

 

[Minder]

Why would other manufacturers make so many variations of the same three-pin design?

They come in different sensitivities and also Unipolar, Bipolar and Bipolar latch types.
I use the Honeywell SS400 series from Digikey but I'm not sure if they make a SMT version.
M.

 

[Monkeyleg]

The sensitivity is one of the factors I'm trying to figure out. I don't know how to measure that.

If there were a service that could tell me what I have, that would be fantastic.

 

[Minder]

The sensitivity of the sensor is based on the required magnetic strength (gauss) at the point of detection (distance),
See chart:
http://sensing.honeywell.com/honeywell-sensing-ss400-series-product-sheet-009050-3-en.pdf
You could always try one with the highest sensitivity.
M.