Thanks. I would argue it's not worst case, it's incorrect - or at a minimum needs clarification from Meraki. The power draw numbers are provided "at full load" which would indicate the switch is providing its full capacity of PoE and has its CPU load pegged. In that case, for a MS390-48FP, it would be delivering 740W of power to the PoE endpoints according to the spec sheet. That's roughly 2500 BTU/hr which is being generated at the endpoints rather than at the switch, and turns out to be the bulk of what a simple calc would indicate is generated within the closet. Too much cooling capacity can cause issues just the same as too little. When an air conditioner short cycles because it's oversized, it won't run enough to control humidity.
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