a. Front Panel Controls and Indicators.
(1) Display. A 3 1/2 digit led display that indicates the results of the
measurements being made. Decimal points are placed automatically, and the units of
measurement are shown on the mode switch (number 1).
(2) Mode switch. Sets the type of measurement to be made. The last position
of the mode switch, ECG, enables the ECG selector switch (number 7). This allows you to
make measurements for the ECG patient lead and isolation leakage current.
DC ONLY switch. Changes the measurement mode from ac+dc to dc only
(4) Current source active led. Illuminates indicating the current source is
internally connected to the test lead jacks during ground resistance measurements
(5) Polarity switch. Selects normal or reverse polarity of the hot and neutral
lines to the test receptacle. This is a three position switch. In the center position, the
switch shuts off power to the test receptacle (number 5).
(6) Ground switch. A momentary switch to open the ground connection to the
test receptacle (number 6).
(7) Electrocardiograph selector switch. Sets the ECG lead test to be made. The mode
switch must be in the ECG position to activate these measurement selections (number 7).
ISO test. Connects the line voltage to the ECG binding posts (number 8).
This voltage is 120/230vac, and it is limited to 1ma. Do not touch the UUT,
patient leads, or safety analyzer during this test since line voltage is
applied to the ECG binding posts.
PATIENT SAFETY PRECAUTION
Since the test method injects potentially hazardous current levels
into the ECG and the related power system, do not conduct tests in
an occupied patient location or while the patient is connected to a
related power system branch circuit.