GE H41542LA, Базовое руководство по обслуживанию

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GE M
EDICAL
S
YSTEMS
D
IRECTION
2317229, R
EVISION
3 LOGIQ™ 180 B
ASIC
S
ERVICE
M
ANUAL
Chapter 10 Quality Assurance 10 - 17
10-7-6 Probe Leakage Current Test
10-7-6-1 Definition
This test measures the current that would flow to ground from any of the probes through a patient who
is being scanned and becomes grounded by touching some other grounded surface.
10-7-6-2 Generic Procedure
Measurements should be made with the ground open and closed, with power line polarity normal and
reversed, and with the unit Off and On. For each combination, the probe must be active to find the worst
case condition.
NOTE:
Each probe will have some amount of leakage current, dependent on its design. Small variations
in probe leakage currents are normal from probe to probe. Other variations will result from
differences in line voltage and test lead placement.
10-7-6-3 General procedure
Follow these steps to test each transducer for leakage current.
1.) Turn the LOGIQ™ 180 unit OFF.
2.) Plug the unit into the test meter, and the meter into the tested AC wall outlet.
3.) Plug the external probe into the meter's “EXTERNAL” connector.
4.) Set the meter's “FUNCTION” switch to EXTERNAL position.
5.) Connect the probe for test with the connector of the console.
6.) Add the saline probe and the imaging area of the probe into the saline bath.
7.) Have unit power ON for the first part; turn it OFF for the second half.
8.) Depress the ISO TEST rocker switch and record the highest current reading.
9.) Follow the test conditions described in
Table 10-49 for every transducer.
10.)Keep a record of the results with other hand copies of PM data.
Figure 10-68 Set Up for Probe Leakage Current
POWER
OUTLET
H (BLACK)
POLARITY REVERSING SWITCH
MOMENTARY
SWITCH
N (WHITE)
G (GREEN)
LEAKAGE TEST
METER
CONSOLE
PROBE