Remote sounder activation: via N/O contacts Detection zones: 2, 4, 6 or 8. Maximum zone capacity: 32 per zone. Sounder activation delay: 0-9 minutes in 1 min increments System voltage: 24 V DC nominal (18 - 32 V). Mains voltage: 230 V AC +/- 10)%, 50/60 Hz. Dimensions: 355 x 275 x 100 Approved to EN54-2 & 4.