GE MEDICAL SYSTEMS
DIRECTION 2300000, REVISION 2 LOGIQ™5 SERVICE M ANUAL
10-16 Section 10-8 - Grounding Continuity
10-8-2 Isolated Patient Lead (Source) Leakage–Lead to Ground
10-8-2-1 Definition
This test measures the current which would flow to ground from any of the isolated ECG leads. The
meter simulates a patient who is connected to the monitoring equipment and is grounded by touching
some other grounded surface. Measurements should be made with the ground open and closed, with
power line polarity normal and reversed, and with the ultrasound console Off and On. For each
combination the operating controls, such as the lead switch, should be operated to find the worst case
condition.
10-8-2-2 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 operating controls such as the lead
switch should be operated to find the worst case condition.
CAUTION
Equipment damage possibility. Never switch the Polarity when the unit is powered ON. Be sure
to turn the unit power OFF before switching the polarity using the POLARITY switch. Otherwise,
the unit may be damaged.
Figure 10-4 Test Circuit for Measuring Non-Isolated
Patient Leads
Table 10-17 Testing Power Conditions
ECG Power Meter’s Polarity Switch Meter’s Neutral Switch
ON NORM CLOSED
ON NORM OPEN
ON REVERSE CLOSED
ON REVERSE OPEN
OFF NORM CLOSED
OFF NORM OPEN
OFF REVERSE CLOSED
POWER
OUTLET
H (Black)
N (White)
G (Green)
Internal
circuitry
Insulating surface
Polarity reversing switch
(use both positions)
Appliance power switch
(use both "off" and "on" positions)
Patient connected leads
The connection is at service entrance
or on the supply side of a separately
derived system
Building
ground
Grounding contact switch (use in both
"open" and "closed" positions)
Current meter
H = Hot
N = Neutral (grounded)
G = Grounding conductor
H
N
G
Patient lead selector switch (if any)
(activated as required)
Appliance
Between each patient
lead and ground