The maglocks we installed had a field sensor that measured the bond strength. The LED on the maglock would turn red when powered and then turn green when the b

The maglocks we installed had a field sensor that measured the bond strength. The LED on the maglock would turn red when powered and then turn green when the bond strenght was correct. Even a tiny piece of paper would keep the LED from going green. Same with a slightly misaligned plate on the door. Pain in the ass since our controllers would not show the door secure until it was perfect.