Hi,
I have RB5009 router (Product Code: RB5009UG+S+IN)
I have noticed that its temperature is stable at 53°C at 0-1% of CPU usage. Also, it sometimes reaches 59°C when there is a lot of traffic going on (around 700Mbs with CPU usage of 5%)
1- Is this a good or an acceptable range of temperature?
2- At the product website, I noticed that the tested ambient temperature is in a range of -40°C to 60°C. Does that mean the router is not recommended to be working at any temperature of 60°C?
3- Does it require to be placed near a fan for an air flow to go through the back heatsink of the router? The room temperature sometimes reaches a max of 35°C during the day.
The current router configuration:
RB5009UG+S+.rsc (12 KB)
I don’t have that particular unit, but yes, electronics are generally quite happy in the 50-60°C range. I don’t start to worry until they’re past 80°C, as a rule.
Does that mean the router is not recommended to be working at any temperature of 60°C?
If it did, they would use the word “absolute,” not “ambient.”
Does it require to be placed near a fan for an air flow to go through the back heatsink of the router?
I would expect to find operating requirements in the router’s manual.
The room temperature sometimes reaches a max of 35°C during the day.
Otherwise stated as “maximum ambient temperature.” You are observing a ~20°C rise over ambient. You would therefore not expect to hit my 80°C threshold until the ambient temperature is 60°C absolute under those conditions.
I have the same device (one of my own, one with a customer).
It’s passively cooled (the WHOLE case is a heatsink 
).
The one with my customer is currently at 37 C BUT located in a server rack in an AC controlled room at 21C. Acting as DHCP server and capsman controller.
At home it shows 48C (located in a small closed cabinet and I guess it’s about 22C in that room right now, in that cabinet are also a modem and digital TV box, so lots of heat being dissipated there). Main router for SOHO.
Given the restrictions on ambient temperature, you will be perfectly fine as long as you stay within the limits.
Actively putting airflow towards the device, will help obviously in further cooling it down but it should not be needed.
The RB5009 runs cool if it is unplugged.