Table 7. Fan operation properties per model
M4250-16XFM4250-12M2XFM4250-10G2XF-PoE++M4250-10G2XF-PoE+M4250-10G2F-PoE+Fan Mode
Off mode
≤ 172F (78C)≤ 147F (64C)≤ 152F (67C)≤ 111F (44C)≤ 108F (42C)Temp.
sensor
N/AN/A≤ 45W≤ 90W≤ 80WPoE budget
See Note 2See Note 1Full traffic loadFull traffic loadFull traffic loadLoad
OffOffOffOffOffFan use
Quiet mode with fan use below 25%
< 152F (67C)< 136F (58C)< 120F (49C)< 98F (37C)< 97F (36C)Temp.
sensor
N/AN/A< 90W≤ 240W≤ 125WPoE budget
Full traffic loadFull traffic loadFull traffic loadFull traffic loadFull traffic loadLoad
< 25%< 25%< 25%< 25%< 25%Fan use
Quiet mode with fan use from 25–100%
≥ 152F (67C)≥ 136F (58C)≥ 120F (49C)≥ 98F (37C)≥ 97F (36C)Temp.
sensor
N/AN/A≤ 720W≤ 240W≤ 125WPoE budget
Full traffic loadFull traffic loadFull traffic loadFull traffic loadFull traffic loadLoad
≥ 25–100%≥ 25–100%≥ 25–100%≥ 25–100%≥ 25–100%Fan use
Cool mode
100%100%100%100%100%Fan use
Note 1. The fans for this model can function in Off mode only if a maximum of eight
Ethernet port are operational (only four ports in the range from 1 to 8 but all ports in
the range from 9 to 12) and if no SFP+ ports are operational.
Note 2. The fans for this model can function in Off mode only if a maximum of eight
SFP+ ports are operational.
Example of intelligent fan operation:
If the fans of model M4250-10G2F-PoE+ operate in Off mode and either the temperature
detected by the temperature sensor exceeds 108F (42C) or the PoE budget exceeds
80W, the switch automatically places the fans in Quiet mode or Cool mode so that the
fans operate between 25 and 100 percent speed.
Hardware Installation Guide29Hardware Overview
AV Line of Fully Managed Switches M4250 Series