This Alarm& Monitoring Indicator is a tower crane safety system. It has the following functions: Working temperature: -20 --- + 60 -40 --- + 80 Working humidity: ≤ 95%/25 Combined error: 1% Power supply: AC220V (to be customized according to clients requirement) Parameter: Rated load, actual load, angle of the jib, hook height ,slewing angle and moment percentage Signal lamp&buzzer: Flickering yellow lamp and buzzers discontinuous response indicates early warning, whereas red lamp and buzzers continuous response indicates alarm and relay outputs. Other functions: Records downloading; sensors self-diagnostic; remote control, zone protection, applicable to luffing tower crane with variety of falls.