Temperature questions

[j-gray34]

I'm trying to find documentation (if any) on optimal temperature(s) for a CS300.

Spec sheet shows 50-95F for operating temp, which I assume is ambient room temp. I also understand the unit alarms at 109F internal and shuts down at 122F internal.

Can anyone say, definitively, what the optimal average internal temp is and/or optimal intake temperature?

Currently, our small data center maintains temp at 70F with good airflow and circulation. This yields 95-97F motherboard temps, and 66-72F backplane temps. According to support, the average internal temp (not visible via the GUI) runs at 35-36C (95-97F) and these average temps cause the fans to run at 100%.

Any information is appreciated.

[j-gray34]

Alternatively, does anyone have any anecdotal info or stats?  I'd be curious to know what your ambient room temp and/or intake temp is versus motherboard temps?

Thanks much.

[chrisk110]

We are in a similar situation having taken delivery of a CS500 last week. It has been racked in a room with efficient A/C and the room temp is 20.5 C.  The fans are running almost flat out and the speeds.  I am unsure what normal speed are so I look forward to hearing any info on this.  I have asked our local Nimble engineer this also and awaiting an answer.

 

[j-gray34]

Thanks for the info, Chris. I'm interested to hear what your engineer has to say.

[chrisk110]

He stated, " That fan RPM looks about right."  No this is our local engineer who I have only met a couple of times and have no reason to not trust.  We'll wait & see if they settle down or it is the way it is.  

I'd be interested to see what stats you guys have on your arrays.  Are you able to post similar images from your arrays for a comparison for me?

[j-gray34]

Support spent a lot of time with us monitoring temps (which we greatly appreciated), but ultimately told us that we were "well within the operational limit of the array".  However, at a constant 95-100% RPM, it feels like we're at the upper end.  Given increasing pressure to reduce cooling demands (not just us, but across the industry), I'm a little concerned.

Here's our 'norm':

[nibbler125]

I have the same problem.  Surely Nimble should have designed their hardware to not run the fans at 100% when the datacenter temps are below 20 degrees?  Or at the very least release a patch that makes the fan RPM more 'conservative' under these 'standard' datacenter conditions.  A reduction down to 85% fan speed will surely leave plenty for cooling and avoid a 'noisy nimble' tag.

[jrhall]

I have one of the smallest units in a CS210 (4TB) and the noise is pretty bad here too. (especially so because it's right behind my office with drop ceilings)
Motherboard temp is 22c and Backplanes are 30c on both controllers.
Room temp is pretty constant around 20-21c.

[j-gray34]

What internal temps and RPMs are you seeing, if I might ask?

Unfortunately, it seems like the fans *need* to run at these RPMs in order to keep the internal temps within spec. But I agree --seems like hardware design is at issue here.

[chrisk110]

Their engineer also mentioned that the fan speed is tied to the Motherboard temperature not the back plane temp.  On our CS500 the M/board temps are 32 & 32 degrees and back planes are 19 & 16 degrees.  So reducing the temp in the room has had no effect on the fan speed as the M/board temps haven't changed at all.  I am about to lift the temp in the room back to 21 degrees and stop worrying about it.  Thankfully it's installed in a comms. room in another building and we don't need to go there too often.