|
FYI, only applicable to the part of capacitor discharge test:
7 g2 S9 k' l9 I$ m! D. V- u- FTo ensure patients and equipment operators are not exposed to hazardous energy levels, voltage levels are measured on all mains terminals accessible after disconnection. With the unit) y( {, p) K/ ` m
operating at 110 % of the rated voltage, power is disconnected and the voltage decay at the mains connection is recorded. The voltage should decay to a level of 60 VDC or less within 1 second. The test is repeated ten times for each pair of the measurement points. The theory is that in those ten times, you will catch the AC waveform discharging at or close to the peak of the mains voltage cycle. It is at the peak where you will have the highest voltage and the longest decay
f- y9 ~6 x; x$ c" w ]times. An alternative method of establishing the discharge characteristics of the unit is simply just to monitor the waveform on an oscilloscope and keep connecting and disconnecting the power until a peak reading occurs. By this method, you can see visually when the AC power waveform has been shut off at the peak level and a single measurement can be recorded and reported./ _. q. D7 \& c" F9 F1 y; N
. d/ S+ t4 M4 I' O8 k
Author: Steven Henderson is a Product Safety Manager at Curtis-Straus LLC. |
|