Reports 1-1 of 1 Clear search Modify search
Environmental Monitoring (Environmental Monitoring)
Paoletti - 22:45 Friday 25 January 2019 (44540) Print this report
Mode Cleaner pipe as a possible path for current (and magnetic field) from MCB to CEB

We noticed in 44508 that a magnetic probe, located in "Piscina" (Injection Electronic Room - IER) over the RampeAuto crate, detected the working cycle of the MCB Chiller.

Suspect was that via the Mode Cleaner tube a (ground?) current could flow, generating a magnetic field.

Today we placed the same probe over the Mode Cleaner tube, then a couple of meters apart (as were before when on the RampeAuto crate), and eventually more meters aside (last position see fig.1)

Interesting results: the detected magnetic field (coherent with the Mode Cleaner Building Chiller working cycle) is someway proportional to the distance of the probe from the pipe.

As example see plot 1 and plot 2 (a zoom of the previous), where the magnetic probe was turned away from the pipe: the variation during the Chiller ON-OFF period was little when the probe was far from the pipe.

Also in spectrigram (plot 3) the general noise is reduced.

This deserve more attention.

According to the Vacuum crew, breaking the electrical continuity of the pipe is easy, but need a week for the No-vacuum / Vacuum cycle.

Images attached to this report
Comments to this report:
Paoletti, Fiori - 11:17 Tuesday 09 July 2019 (46302) Print this report

As a further check we used a portable magnetic field meter: when placed over the MC pipe the 50Hz magnetic field is about ten times higher (500nT) than when we measure far from it (50nT).

Images attached to this comment
Search Help