Very big ferrite EMI cables core

I've an industrial device that is susceptible to EMI at about 67 MHz and 120 MHz. I want to place some ferrite chocke along the cables that come in to that device but the cables are interested by very high currents (from 150A up to 1000A ). Obviously these cables have a generous section in fact the maximum external diameter of the cables is 26.4 mm.
due to the extremely high currents I think I'm obliged to use the common mode soution to prevent the core saturation.
Do you know some producer of cables cores big enought to use with two cables?
Thank you

I do not, but have you considered something like
ferrite powder, binder and mold your own? If this is
a one-off, buy yourself a cake mixer, some pourable
epoxy and a pound of ferrite powder....

You might get better results inside the case, find
the "victim" and I'd bet that it is fed much lower
current that allows commercial common mode
choke cores (or, just solder in a canned common
mode filter, like Corcom et al make).

You can have ferrite toroid with 150 mm inner diameter and even larger amorphous metal tape wound cores, specially designed as power electronics common mode filter. See e.g.

67 MHz and above is however not in the typical conducted EMI range, we can expect that the emissions are coupled to other circuits and case metal before they arrive at the common mode choke and thus bypass it.

dick_freebird said:

I do not, but have you considered something like
ferrite powder, binder and mold your own? If this is
a one-off, buy yourself a cake mixer, some pourable
epoxy and a pound of ferrite powder....

Click to expand...

Great suggestion! This is not a one-off case but if we find a working solution is a good things anyway.

dick_freebird said:

You might get better results inside the case, find
the "victim" and I'd bet that it is fed much lower
current that allows commercial common mode
choke cores (or, just solder in a canned common
mode filter, like Corcom et al make).

Click to expand...

It seems the only victim is an hall effect current sensor that sense the main current (in the order of hundreds of Amperes). Probably the EMI couples with that power cabels.

FvM said:

You can have ferrite toroid with 150 mm inner diameter and even larger amorphous metal tape wound cores, specially designed as power electronics common mode filter. See e.g.

67 MHz and above is however not in the typical conducted EMI range, we can expect that the emissions are coupled to other circuits and case metal before they arrive at the common mode choke and thus bypass it.

Click to expand...

We've a metal enclusure that is not connected to the earth via any cables and we discovered the susceptibility of the device because of IEC 61000-4-3 and 61000-4-6 tests. The only 3 cables that enters into the device are: two power cables (external diameter of 26.4 mm max), and a signal cables (external diameter of 7.5mm).

Unlikely that a hall effect sensor picks up RF from the power circuit. Did you ever try to add bypass capacitors to the sensor power supply and a common mode choke to the signal cable?

The Hall Effect sensor is a sensor of **broken link removed**.
The problem we have is that, in presence of EM disturbainces (those described by the mentioned standards), the hall effect sensors give an output that is non proportional to the real current that flow. This is the same either, with the LEM sensor of our system, and with an external **broken link removed** (battery powered). The amount of the error is exactly the same for both the sensors. This is beacuse I think it is due to the high frequencies coupled with the power cables. Maybe it is due to the non linear elements inside the op-amp of the hall effect current sensor.