User manual
16 
TDK-Lambda 
GWS 2
50 
Series 
INSTRUCTION MANUAL 
The Output Derating with external fan depends on the airflow conditions and the temperature rise for the components. 
The method stipulated below provide a way to decide for the safe operation of this power supply. As shown, this table 
provides a list of the maximum temperature allowed for specified components. The component temperature is measured 
according to IEC60950-1 2nd edition Clause 4.5. 
Maximum rated temperature for these components are taken from the component specification provided by the original 
manufacturers. These are the worse case allowable temperature. 
Temperature is measured using thermal couple K-type, and using CYANOACRYLATE adhesive or equivalent to secure 
to the hottest point of these components. 
In order to decide the worse case temperature rise, the selected measurement point should not face direct airflow and the 
equipment powered should operate under worse case operating conditions. 
*1. Absolute temperature (Maximum temperature) during normal operating conditions. 
 Higher temperature will probably cause shorter life span for the power supply. 
Please refer to the component side layout drawing below for temperature measurement. 
Airflow should cool down all the components evenly. 
Location No  Parts Name  Maximum Temperature (
o
C) *1 
D1  Bridge Diode  100 (130) 
D18/Q11  Schottky Diode/Mosfet  85 (130) 
C14  Electrolytic Capacitor  60 (105) 
T1  Transformer  95 (130) 










