SPDU: Sequential Controlling PDU is an intelligent product developed and produced by CLEVER. CLEVER SPDU According to customer's requirement, set the order of power on/off and delay interval of outlets to achieve sequential power on/off which can avoid the instantaneous power resulting from the current shock when many equipments power on/off simultaneously and can protect the electric equipment to run safely and reliably and meet with the technical requirement of system operation. CLEVER SPDU has 6 series: SPDU2000, 2100, 3000, 3100, 4000, and 4100. CLEVER SPDU are widely applied to 19〞standard and nonstandard server cabinet or network cabinet. They can be horizontally or vertically installed. SPDU2000 and 2100 series are applied to 482.6mm（19"）cabinet, horizontally installed. SPDU3000, 3100, 4000 and 4100 series are applied to 482.6mm（19"）cabinet, vertically installed. Main functions 1. Sequential power on/off   2. Sequential power on/off in group 3. Configure the interval time 4. Selecting function 5. Dynamic adjusting and keeping function 6. Reset/Refresh function 7. Start/Stop function 8. Overload protection 9. Immediate cut off function 10. Digital voltage meter/ ampere meter 11. Display the operating state 12. Display the output state 13. Multi-standard sockets 14. Socket with anti-fall device