Thermal Evaluation
June 12 2014
 |
 |
Purpose:
To determine the effectiveness of the chassis thermal design at room temperature. Also, to determine if the unit is thermally protected if four cooling fans were to malfunction and to compare results with previously released storage units.
Description:
The tests are performed at an ambient temperature of 25 degrees Celsius. This is roughly 20°C warmer than most server rooms. Numerous thermal profiling tests are completed using 6 fans to cool the unit and also only 2 fans cooling the unit to simulate if 4 fans were to malfunction. All tests in which were performed on the 45Drives Storinator were identically repeated on the Backblaze Storage Pod 3.0.
Thermal Limits:
Hard Disk Drive Specification – Maximum operating environment: 60°C
RAID Host Adapter Specification – Maximum operating environment: 55°C
Test Equipment:
· 45Drives Storinator
· Backblaze Storage Pod 3.0
· 45x Seagate 4TB Desktop Hard Disk Drives – ST4000DM000
· Omega Thermometer – HH501DK
· Omega Type K Thermocouples (±2.2°C)
· EKCO Timer
Test Procedure:
· Eight Thermocouples were placed inside both the 45Drives Storinator and the Backblaze Storage Pod–Drive Bays according to the diagram below. One thermocouple probe was located inside the motherboard compartment and also one on the exterior of the machine to measure the ambient temperature of the room.
· Machines were loaded up with 45 Seagate 4 Terabyte Desktop Hard Disk Drives.
· Covers were put on and machines were powered up with 6 cooling fans running.
· Temperature readings of a total of 10 probes were taken initially and 15 minute intervals thereafter for 90 minutes. (See Test Data Below)
· The above procedure was repeated on the Storinator and Backblaze Storage Pod 3.0 using 2 fans to cool the machines.
Test Data:
The following is a diagram in which the thermocouples were placed inside the machines.
45Drives Storinator 6 Cooling Fans:
Backblaze Storage Pod 3.0; 6 Cooling Fans:
45Drives Storinator 2 Cooling Fans:
Backblaze Storage Pod 3.0; 2 Cooling Fans:
Conclusions:
45 Drives Storinator
Thermal performance was excellent, the hottest temperature measured was 6.2°C above ambient. This was measured on Probe 9 which was above the motherboard.
With a max allowable operating temperature of 55°C, we could run the Storinator in an environment of 48°C without damaging any of the components. That is over 20°C warmer than at which we conducted our experiments. Keep in mind; it would be very difficult to get a human to work in those conditions. That is why our machines usually operate in nice cool server rooms. But if you wanted to, you could run the Storinator in a 48°C room!
With 4 cooling fans shut down and only 2 running, the Storinator still showed great performance, 11.4°C above ambient was the warmest point, which was again measured on Probe 9.
45 Drives Storinator vs. Backblaze Storage Pod 3.0
According to our results, with all 6 cooling fans running, the Storinator runs 2.1°C cooler than the Backblaze Pod 3.0.
When 2 fans are running, the Storinator again runs almost 5°C cooler than the Backblaze Pod 3.0. Additionally it should be noted that the greatest Δt measurements were observed in the rear corner of the Hard Drive Bay for the Backblaze Pod 3.0; this was not the case for the Storinator where the greatest readings were observed above the motherboard. This was true for both the 6 and 2 cooling fan experiments. We are unsure of exactly why this is; more experiments are currently underway involving the air-flow restrictions of the Port Multipliers and Direct Wired Backplanes.
We would like to thank our two engineering technicians: Rob MacQueen & Ryley Boutilier for their hard work in providing the community with this valuable information