[DG] RF Ground connection

Hi,
I have installed a EV-100 wheel system. In the manual i read that i should also install a RF ground connection.
- is this really necessary? (what could happen?)
- can i just run a cable from the negative battery point to this RF ground connection on the acu-100?
- can i use a normal cable for this or do i need some special (shielded?) cable?

The current negative cable is already coming from the same point.
- can i make a shortcut cable connection on the ACU-100 from the minus to the RF Ground connection?

Gr.
Bram Havers.