ATX/ATX12V Power Supply Design Guide
Version 1.1
Page 29
5. Environmental
The following subsections define recommended environmental specifications and test
parameters, based on the typical conditions to which an ATX and ATX12V power supply
may be subjected during operation or shipment.
5.1. Temperature
Operating ambient
+10 °C to +50 °C
(At full load, with a maximum temperature rate of change of
5 °C/10 minutes, but no more than 10 °C/hr.)
Nonoperating ambient
-40 °C to +70 °C
(Maximum temperature rate of change of 20 °C/hr.)
5.2. Thermal Shock (Shipping)
Nonoperating
-40 °C to +70 °C
15 °C/min
≤
dT/dt
≤
30 °C/min
Tested for 50 cycles; Duration of exposure to temperature
extremes for each half cycle shall be 30 minutes.
5.3. Humidity
Operating
To 85% relative humidity (noncondensing)
Nonoperating
To 95% relative humidity (noncondensing)
Note: 95% RH is achieved with a dry bulb temperature of
55 °C and a wet bulb temperature of 54 °C.
5.4. Altitude
Operating
To 10,000 ft
Nonoperating
To 50,000 ft
5.5. Mechanical Shock
Nonoperating
50 g, trapezoidal input; velocity change
≥
170 in/s
Three drops on each of six faces are applied to each sample.
