In this case maybe. But might be a little large for a 230v 100amp scrap yard magnet!

Likely so.
Any idea what the inductance of such a magnet is?

 

Likely so.
Any idea what the inductance of such a magnet is?

No real idea, there are two main suppliers of reverser's on Locomotive magnet cranes and they both use a reverse shot to release.
In times of high usage when the mean temperature is high, the operators usually have use a water bath to dip the magnet in occasionally for cooling, due to magnetism loss.
Max.

 

I've worked with the big scrap yard electromagnet systems for years now. Even built custom solid state control systems to update older DC generator powered units, with the old fashioned huge 'click and bang' (arc and burn, really) type mechanical controllers, over to run off modern 3 phase brushless gensets.

Controlling your release and drop times are pretty simple. Just add a flyback diode of equal current rating to whatever the electromagnet uses along with a series resistance of 2 - 3 X the electromagnets own resistance.

The series resistance will allow the inductive spike voltage to shoot up thus letting the magnetic field collapses faster. I use a ~ 10 - 12 ohm series resistance (~500 watt) with 240 VDC 60 - 80 amp (~4 ohm cold) electromagnets and they are very fast and clean on the drops.

As for the switching I use all solid state devices such as 120 volt 600 amp IGBT devices for the main control and three phase SSR's for the AC end switching. All very simple and very rugged.

For your 24 volt unit I would recommend a SSR device that has at least a 100 volt rating and a current capacity of at least 3 - 4X what ever your electromagnet uses and a series resistor with a wattage rating of about 5% of whatever your electromagnet cold running wattage is.

With that, inductive feedback should not be hurting the batteries any more and any further damage to them will be coming from the charger side.

 

The ones I have worked on were Ohio Locomotive Magnet Cranes used by most N.A. R.R.s.
The controller used was either GE or Hubbel, with the Hubbel being the slightly superior make.
GE used a contactor reverse shot to release, the Hubbel used a patented Discharge module.
Both uses a diesel ran DC 240vdc generator.
Max.

 

Pretty much the same units I have worked on for years.

Overpriced for their age of technology for what they do as I see their designs.