K1 | Relay 1, DPDT relay, dry contact, digital input 1 for fan high speed with W1 call |
K2 | Relay 2, SPST relay, dry contact, digital input 2 for fan low speed with Y1 call |
K3 | Relay 3, SPST relay, dry contact, digital input 3 for fan low speed with G call |
K4 | Relay 4, DPST relay, dry contact, digital input 4 for fan high speed with Y2 call |
