Kongsberg EM 712, Maintenance Manual

Page: 133 / 232

451106/B
133
Maximum coverage and depth
Beamwidth 0.25 x 0.5 0.5 x 0.5 0.5 x 1 1 x 1 1 x 2 2 x 2
Maximum coverage
Winter * 3800 3600 3450 3250 3050 2850
Summer * 4400 4200 3950 3700 3550 3250
Maximum depth
Winter *
3400 3200 3000 2900 2700 2600
Summer * 3600 3400 3200 3100 2900 2800
Estimated depth and coverage for EM 712, based on BS= -20dB, NL= 35 dB, f = 40 kHz
Dual swath restrictions
FM mode is used to extend the maximum range capability.
Since the relative ping rate increases at large depths (caused by reduced angular
coverage), the need for dual swath decreases with depth. In the Very Deep and Extra
Deep modes long FM pulses are prioritized, so dual swath is not available in these modes.
Reduced power output (Mammal protect)
Maximum intensity is encountered in a thin wedge extending below the ship with an
angular coverage of about 140°. The intensity level may be lowered by 10 or 20 dB by the
operator. The EM 712 may be set in a mode to begin pinging with a flexible soft-start as
a possible means of inducing marine mammals to leave the area of high intensity sound.
Technical specifications