Home Forums General Discussion Technical Questions Dover composite upper floors won't go to lower flo

Hi all, these composites strike again. Im having an issue with a 17 stop car where floor 10 through 17 won't take a down call to floor 7 or lower. You have to run the car to 8 or 9 and then place a down call to the lower landings. The lower landings will run to any floor. Ive been through the selector contacts but haven't found anything unusual. Im.suspecting a group issue but unfortunately dont have the group prints available. Any insight or direction to start would be invaluable.

Sounds like the problem is in the S-circuit. When you set a call with the car at an upper floor, does the SD (signal down) IBM relay energize? Is the DP (down preference) IBM relay energized? If SD is in, is DA (Down Holding) IBM relay in? S-circuit is controlled by the most outboard row of switches when the drum is on the left.

Where are you located?