User Manual LKG 601
16
Theory of Operation
The LKG 601 circuitry can be divided into main functional blocks as shown in Figure 3.
Each performs a key role in the operation of the instrument.
Figure 3
Functional block diagram of the LKG 601
Block Diagram Description
Test Load:
The input test load is user selectable to AAMI ESI –1993 or to IEC 601.
RMS Converter and Amplifier:
The input amplifier buffers the input. The RMS
converter generates a DC voltage equal to the RMS value at its input. The gain
Amplifier sets the gain for the measurements. When the MODE switch selects leakage
current measurement, the AAMI LOAD is connected in front of the INPUT AMPLIFIER,
and the voltage developed across it from the leakage current is measured.
Current Source and Amplifier:
Resistance is measured by connecting the
current source to the resistance to be measured and measuring the voltage with the
input amplifier.
Test Receptacle:
This supplies power to the unit under test, 110 VAC rated at 15
Amps (220 VAC). The rocker polarity switch selects NORMAL, OFF and REVERSES
polarity in the test receptacle.
Display:
All measurements are displayed on a 3-1/2 digit LED display. Over range
is indicated by showing a 1 in the most significant digit
FU
NC
TI
O
N
SEL
EC
TO
R
AAMI or
IEC 601
RMS TO
DC
CURRENT
SOURCE
LEDS
DI
SP
LAY
AMP
TEST
RECEPTACLE
