12Figure 2- 92.4.2 Electromagnetic LockWhen VTO connects to electromagnetic lock, it means that the positive end ofelectromagnetic lock connects to NC of VTO (user port 11) while its negative end connectsto COM of VTO (user port 12).When VTO connects to door sensor in electromagnetic lock, one end of door sensorconnects to FEEDBACK of VTO (user port 8) while the other end connects to GND of VTO(user port 9). See Figure 2- 10.Figure 2- 10