Philips EPIQ 7 User Manual page 195

Leakage Current Testing for Intraoperative Transducers
L
N
E
Test 2: Leakage Current Test with Mains Voltage Applied (Sink) for Intraoperative Transducers
Key to Test 2 Diagram
C
Z
A
e
EPIQ 7 User Manual 4535 617 25341
Line mains supply
Neutral mains supply
Earth ground
Stray capacitance from the ultrasound system power wiring to the system
grounded metal chassis (1 to 3 MΩ reactance)
Impedance between the metal parts of the transducer and a test electrode placed
in the bucket of saline solution (about 850 kΩ with an intact outer insulating layer,
500 Ω with a hole in the layer)
Microammeter to measure leakage current from a line supply to the transducer
and back to earth ground through electrode Z and the equipment chassis
Line power source, either 110 Vac or 220 Vac
Intraoperative Transducers
195