[GreenKeys] Measuring Electromagnet Saturation?

[Brooke Clarke]

Hi Bob:

I've been doing my homework on electromagnet saturation and found Electrical 
Silicon Steel as used in transformers, motors and newer electromagnets.  Not 
only higher saturation but also less remnant magnetization.  That's what's used 
as the core of the Synchronization coil in the WU 37SS clocks with the Sweep 
Second hand.  They were synchronized once a day using what looks like a 
Teletype loop running at 120 Volts and adjusted to 1/4 amp.  A one second pulse 
that ends at the top of the hour was used.

In trying to come up with a circuit to drive the sync coil I'd like to have a 
way to know that the electromagnet is in saturation.

Any thoughts on a test that would demonstrate saturation of the electromagnet?

Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.precisionclock.com