Hi,

I have this sensor --> Hall sensor to install it on my bike using an arduino nano.

I was expecting it to be a NJK-5002C, but it doesn't look like it is. I'm struggling trying to figure out the pinnout, any help is welcome.

It has a 3 pin automotive connector, with red, green and yellow wires.

I have tried using my multimeter to find out the actual pinnout, to no avail.

I have tried all permutations measuring in both resistance and diode mode. Only 2 readings show up, all the others are .0L
Resistance: Red(+), Green(-) = 27.8M
Diode: Green(+), Red(-) = 0.6637

Does this make any sense?

Link to NJK-5002c sensor datasheet

 

Hi Dav,
I would connect the Red wire via a 4k7 resistor to +9V, Green wire to 0V of the supply,
Measure the resistance between the Yellow and Green and place a magnet near the face of the
Sensor.
Post what you measure.
E

 

Hello,

That is the stupidness of sellers at aliexpress and ebay.
They do not provide the datasheet or how to connect the devices.
They simply want to sell without knowing what they are selling.

Bertus

 

Hi Dav,
I would connect the Red wire via a 4k7 resistor to +9V, Green wire to 0V of the supply,
Measure the resistance between the Yellow and Green and place a magnet near the face of the
Sensor.
Post what you measure.
E

• Red wire via 4k7 to +10v
• Green to 0v

Resistance between green and yellow, always .0L
Voltage in yellow -0.47v without magnet, -0.6v with magnet (Sensor led was not lighting anytime)

 

Diode: Green(+), Red(-) = 0.6637
Does this make any sense?

Yes, if the active device is an open-drain N-channel MOSFET, Green is the source and Red is the drain. That would then be a measurement of the MOSFET's internal body diode.

 

Yes, if the active device is an open-drain N-channel MOSFET, Green is the source and Red is the drain. That would then be a measurement of the MOSFET's internal body diode.

May be I'm not understanding right.. but I supose that mesaurements for a diode should be:

Positive probe	Negative probe	Resistance	Diode
Green	Red	28M	0.6637
Red	Green	0L	0L

and I'm getting

Positive probe	Negative probe	Resistance	Diode
Green	Red	0L	0.6637
Red	Green	28M	0L

 

They normally have a open collector output which requires a pull-up resistor, also no mention if it is sink or source output?
Also, is it the type that requires a magnet or just ferrous metal version?

 

Also, they do not conform to the industry standard for wire colour.
i.e. Blue = NEG
Brown = POS
BLK = Load

 

They normally have a open collector output which requires a pull-up resistor, also no mention if it is sink or source output?
Also, is it the type that requires a magnet or just ferrous metal version?

The sensor comes with two magnets.

My first try was:

• Red to 10v
• Yellow to 0V
• Green to 10v with a 1K pullup resistor.

Green was 10v no matters what you do with the magnet. Tried the same with yellow wire as output an pullup resistor, 7v no matters what you do with the magnet.

 

May be I'm not understanding right.

The body diode is normally reverse-biased when the FET is in use.

 

Hi again.. I was doing some tests with a cheap DIY tester that y bought as a toy on aliexpress, and surprisingly this is what it detects:


It's strange, because I can't detect the diode between yellow and green with any of my multimeters.
With this, and based on this article I asume:

• Yellow : V-in
• Green : Ground
• Red: out signal

I was testing with this:


tested with 5V, 10V and 12V, with pull-up resistor, with-out it.. and finaly with pull-down resistor. Measuring voltage on red wire I can´t see any reaction to the magnet.

I am thinking that the sensor may be faulty, could it be?

 

I am thinking that the sensor may be faulty, could it be?

Anything is possible !
I only use reputable makes !