K110 MicroProbe

Ask any questions relating to the PicoScope hardware or kit contents here.
If you have any questions prior to purchasing the kit post them here.
Post Reply
Peter704070
OneWave
OneWave
Posts: 15
Joined: Mon Jan 25, 2010 5:52 pm

K110 MicroProbe

Post by Peter704070 »

Hello

I have put a couple of posts up in the past, I work as a lecturer and try to teach students how to use Pico Scope. We have struggled to check the new ABS Sensors and Mass Air Flow sensors, this is due to the fact that the current readings are so low.

As a department we want to buy something that can connect to our PicoScope I've suggested buying a K110 Probe but at a cost of over $650 this is rather a lot especially when we need other important resources.

My question is does anyone know where I can get a K110 Probe at a reduced price or known of anything that will also measure such low current readings.

Thanks
Pete

Alan
Pico Staff Member
Pico Staff Member
Posts: 264
Joined: Thu May 25, 2006 8:02 am

Re: K110 MicroProbe

Post by Alan »

Hi Pete,

For the MAF sensors its better to measure the frequency output rather than monitor the current - that way you are looking at the same signal as the ECU. Look here for more details http://www.picoauto.com/tutorials/testi ... nsors.html

Active ABS sensors switch from 5mA to 15mA (typically) and there are 2 ways of looking at these. The first - on many systems you see a small switching voltage - find which wire has the higher output voltage and then zoom in to see the switching. This example is from an Aston Martin Cygnet (same waveform as a Toyota IQ).
aston cygnet abs.jpg
The other option is to use the existing low amps probe, with care you can just spot the 10mA switching. Select the 500mA range and either use resolution enhancement to 16 bits or set the filter to about 100Hz. If there is any slack cable then pass the wire through the jaws of the current clamp 2 or more times as this multiplies the current (if you pass the wire through the jaws four times then the measured current will be 4x bigger so a signal switching from 5mA to 15mA will look like 20mA to 60mA. Not in the office and can not find an example waveform on this laptop at the moment.

If you want to measure wideband lambda then again the voltage trick works on some of them, but not on others (eg the Toyota AFR sensors). For these if you dont mind messing around one option is to insert a coil of say 50 turns of wire into the circuit (the 6 way break out leads and a bit of thin wire works here). Put the low amps probe around the 50 turns and the 1mA signal is now 50mA.

If however you do a lot of work with these sensors then a probe like the K110 is a good investment rather than the work arounds above. There are a few cheap mA probes from China on ebay (bright yellow) that we have had a look at but they could not pick up any measurable signal in an engine bay so do not waste your money on them. The best place to get the K110 is from our friends at Autonerdz.

Avdr
TwoWaves
TwoWaves
Posts: 157
Joined: Sun Jan 08, 2012 9:25 am

Re: K110 MicroProbe

Post by Avdr »

Hi Pete,

Although its not actually a clamp on probe, I have bought a current sensor that you have to interconnect ie. in series.

It works by a current strap on a chip setting up a magnetic field, which then is converted to an output voltage. I intend to try and market a completed item if I ever get time to get it past development stage.

The chip is an AAV003-10E, which is capable of upto 600ma. Have a google for the data sheet and see what you think.

Post Reply