DC PSUs and supplying DC power to the chassis
The DC version of the generation 1 FortiGate 7121F chassis front panel can include up to eight hot swappable -48V to -60V, 41-33A, 2000W DC PSUs. The DC version of the generation 2 FortiGate 7121F chassis front panel can include up to eight hot swappable -48V to -60V, 52-42A, 2500W DC PSUs. Each PSU has an Internal 60A/170VDC fast blow fuse on the DC line input. See FortiGate 7121F front panel for locations of the PSUs. The diagram shows AC PSUs, with a DC version of the chassis the AC PSUs are replaced with DC PSUs.
The number of PSUs required by a chassis depends on the number of FIMs and FPMs in the chassis. See Power consumption for different FIM-7941F FortiGate 7121F configurations or Power consumption for different FIM-7921F FortiGate 7121F configurations.
Fortinet supplies a DC Combiner that you can install to provide redundant power feeds to each PSU. See Using the FortiGate 7121F DC Combiner to supply redundant DC power for the FortiGate 7121F. Because FortiGate 7121F generation 2 PSUs can supply enough power for 4 x 4 redundancy, the DC combiner is not required for the generation 2 FortiGate 7121F.
Each PSU is designed to be installed in a Telecom data center or similar location that has available -48VDC power fed from a listed 80A circuit breaker. To improve redundancy you can connect each power supply to a separate power circuit.
DC PSU
If you are connecting the generation 1 FortiGate 7121F to Fortinet's DC Combiner, Fortinet supplies custom DC power cables that connect the two-prong power connector on each DC PSU to the corresponding connector on the DC Combiner module front panel. The connector on each end of the cable clicks into a release tab that secures the cable into place. For more information about the FortiGate 7121F DC combiner, see Using the FortiGate 7121F DC Combiner to supply redundant DC power for the FortiGate 7121F.
If you are connecting the generation 1 FortiGate 7121F directly to data center power, Fortinet supplies custom DC power cables that connect to the two-prong power connector on each DC PSU. The connector clicks into a release tab that secures the cable into place. DC terminal rings on the supplied cable must be securely and safely fastened to the your data center power supply terminals.
The supplied DC power cables are intended to be used only for in-rack wiring, must be routed away from sharp edges, and must be adequately fixed to prevent excessive strain on the wires and terminals.
PSU Power ratings
| Max Inrush Current | 50A |
| Max Inrush Current Duration | 200ms |
| Input Voltage | -48Vdc to -60Vdc |
| Input Current | Average: 203A @ -48Vdc and 163A @ -60Vdc for each PSU |