Phase Angle in a Metal Detecting Instrument

... and whats your question now or did you only want to tell us?

The phase angle & signal strength adjustments are used to calibrate the aperature [opening] together with the conveyor & material [cocoa cake]. You should have received operational manuals, calibration samples & support [training], if you purchased this unit new! Here's a link to the corporate website service page http://www.se-so-tec.com/servicing/?n=28 Give them a call [or email] & at least order a manual & the calibration samples.

Most customer service departments for specialized equipment are very helpful. S+S has been in business for many years, I would expect nothing less.

Clement...I feel your pain. I deal with several varieties of cocoa powder in product and they are terrible through a detector. You can imagine how happy I am when we run our "bonus blend" added to products for schools...very high in vitamin, IRON, and minerals. Yes...I feel your pain.

A typical detector uses a low power high freq magnetic field coil. When metal goes thru it creates changes in the magnetic field. The changes in the field generate electrical signals that can be characterized by the parameters Phase and Amplitude.

Different metals and products generate signals with different phase angles. This is what your supplier is referring to. With some frustration and swearing you can "tune out" the signal giving you fits. But you have to find the phase angle of it and that can be tedious. I have one dark dark powder that is at about 5250. I cancel that out and I'm on the ragged edge of not rejecting non-ferrous. It takes some effort to get the exact angle and sensitivity to do both. You need to minimise the effect of the cocoa but still reject to standards. I also use a cocoa that cancels around 2420. Note that the further away from 0000 phase (vibration) the smoother your conveyor and transition, etc. need to be. You can "cover" the cocoa...and then find that every little bump causes the detector to spike and reject. If you know any other producers that use this same stuff...call them. Also call your cocoa supplier...they very well may have the phase number already. Below is the references for metal detectors that are typical.

So..like your supplier has said...you'll need to familiarize yourself with your detector and spend the time required to find where your cocoa is reacting...best to do it offline...not while you are trying to run production.

If equipped turn your reject horn and/or reject device off. Turn your sensitivity up...so you can see the cocoa causing about 2/3 reaction on the meter. Then start adjust the phase discriminator up...I go up 50 at a time. Run product ... watch the meter ... go up... run product..and so on. When you get in the area you will see that your meter does not react up to the same level. Now you have to fine tune. Keep your standards handy and fine tune so you pass the cocoa but reject the standards.

Good luck...by the time you find this cocoa and blank it out you'll be seeing that detector in your dreams.

And...thank you so much for not having a super rich dead uncle in the Ministry that needs me to help get the millions of dollars free ... uhm, sorry...bad joke... seriously, good luck...hope this helps.