14 ALGO® 5 Newborn Hearing Screener Service Manual
P/N 000976 Rev.A
2. Using an Ohm Meter, measure impedance between the positive and negative
contacts to get a baseline impedance.
3. Using the Ohm Meter, measure the impedance from the ground pin on the outlet
plug to any screw on a cart column, such as the bracket that attaches the panel
PC to the column.
4. Subtract the measured value from the baseline value measured in step 2 to get
the ground integrity value. Verify that the impedance is less than 100 milliohm
(0.1 ohm).
5. Ground integrity should be checked whenever a shelf is adjusted in height.
100 milliohms or less
TABLE 1: Ground Integrity
2.3.2. Earth leakage current
AC
Polarity
Line cord Neutral cord IEC 60601-1 UL 60601-1
ANSI/NFPA 99
Normal Closed Closed 500 µA 300 µA
Reversed Closed Closed 500 µA 300 µA
Normal Open Closed 1000 µA 500 µA
Normal Closed Open 1000 µA 500 µA
TABLE 2: Earth leakage current
2.3.3. Enclosure leakage current
AC line
cord
polarity
AC line cord
neutral
conductor
AC line cord ground
conductor
IEC 60601-1 UL 60601-1
ANSI/NFPA 99
Normal Closed Closed 100 µA 300 µA
Normal Closed Open 500 µA 500 µA
Normal Open Closed 100 µA 300 µA
Reversed Closed Open 500 µA 500 µA
Reversed Open Closed 500 µA 300 µA
Reversed Closed Open 500 µA 500 µA
TABLE 3: Enclosure leakage current