Fortigate 3950B power

[amargys]

Hi All, Has anyone have experience with FGT 3950B? I'm facing the issue where device doesn't power on. I have 2 of them one is used and another was brand new and sealed. To power them on C19 cable needs to be used, so I went ahead and purchased it. Once connected green light on PSU comes up but it's blinking and the firewall doesn't power on. I've purchased another cable and connected second PSU, but getting the same result on both firewalls. What could be a possible issue for this? Thinking like my house socket's aren't powerfull enough or specific cable is needed etc? Or maybe there is some secret switch needs to be turned on? Thanks,