@Edward Paul posted:Is there any similarity to the old Super - O part No. 37 uncoupler?
It is essentially a knock-off. If it is not working, the magnet itself has likely overheated and failed or the fine wires under the track which connect to the outside rail and/or screw terminal either have broken off or are not making proper contact.
On both styles, "ground" power (U, "black", etc) is obtained through the layout (common ground) and "hot" is obtained via the switch and transformer terminals ABCD, "red" etc.
See here and my quoted response here for additional information and discussion.