Hello,
I would like to vary the magnetic permeability of a cored coil using an electromagnet, taken out from a relay.
I want to be able to apply from very small magnetization to the coil, up to quite large, so I need high magnetization dynamic range (if such term exist).
For that purpose:
1. What types of relays should I best choose?
2. What voltages of relay coils should I choose?
3. I guess, the more turns in the relay coil the best? (if so, greated coil voltages have more turns?)
For example I have seen this relay
https://www.surplussales.com/Relays/REContOF-2.html the "very sensitive type", which operates even at 2v. Will in general low voltage relays have more turns, so they can produce more magnetization force?
As I said, my interest is not on the pull-in voltage but using the relay coil as an electromagnet.