Operating temperature defines the ambient temperature conditions under which a power supply can operate safely and meet its performance specifications. This is typically expressed as an operating temperature range (e.g., 0°C to 40°C).
Unless otherwise specified, this rating assumes the unit is placed horizontally in still air (without wind). Operation outside these conditions, such as placing the unit vertically or at an angle, may affect performance.
For forced air-cooled power supplies, the operating temperature is measured at the air intake (the airflow into the power supply).
Note on Lifetime: Operating temperature significantly impacts the power supply's lifespan. As a general rule, every 10°C rise in operating temperature can reduce the unit's lifetime by 50%. Therefore, operating the power supply at the lower end of its specified temperature range will help maximize its longevity.