Current clamps repair

[Simon123]

Hello!

I found this piece broken in my current clamps.
What is it?
Looks like, bond wires went to thing in the middle.

[SeanB]

It was a hall sensor chip, bare silicon that gives a very small differential voltage output that varies according to the magnetic field through the face of the chip. Generally does the DC current sensing side, with a wound call that does the AC field side. Sadly if you do not have a chip wire bonder it is not repairable. Not likely to be easily available as a spare part either. Might come as the complete meter or the complete clamp assembly.

[Simon123]

Its iskra meter, i bought it cheap on flea market.
At least voltage and resistance measurment is working.
Could i just use hall sensor from fan?
Or modify it to measure AC only?

[SeanB]

Hall sensor from fan generally has some conditioning electronics inside. Look at older FDD drive motors, you might find one that has 4 wire hall sensor chips to sense motor drive. A small square black block ( there will be 3 of them connected in parallel on 2 wires and 2 leading to the motor drive chip) under the stator on old 5 1/4 inch drives, and then you can place this on a small board in place of the sensor. May not be accurate any more but probably will work somewhat. Post pics of the main board and the rest of the meter.

[Simon123]

https://plus.google.com/photos/yourphotos?pid=5994075362018111826&oid=105582581813039352395
3 pictures
Its pretty old-1988(the same brand as Digimer 10.
It had sticker, that it was last calibrated on 2009, but i cant see any new trimmer glue, so they proably just tested it.
It uses intersil 7106 lcd multimeter driver.

[Simon123]

I tried this sensor, but it doesnt work properly.
Current gets close to 5A in 200A position, but A adjust doesnt work and it doesnt measure current.