6CP50/10-3
4-3
ELECTRICAL SETUP
GROUND-GUARD-RETURN CONNECTIONS
The base of the High Voltage transformer contains a currentmeter feature useful in measurement of different
current sources. (Refer to Figure 4-1.)
1. Standard Mode (RTN)
The standard configuration is set up to measure the current from the high potential side of the unit under
test to ground. This configuration must be used if it is not possible to isolate the low voltage side of the
object under test from ground.
The low potential side of the unit under test is connected directly to ground. The binding post Jumper
Clip is installed between the Ground (“GND”) and the Return (“RTN”) posts on the base of the H. V.
Transformer.
This measures the output current flowing from the high voltage output through the unit under test to
ground and the current meter then senses the return current from ground to the “RTN” terminal of the
high voltage transformer.
2. Guard Mode
For test objects that can be fully isolated from ground it may be desirable to use the Guard Mode. In this
mode only current passing through the test object will be displayed on the current meter. This will be
especially important if very small currents are to be observed.
In this mode the current path does not flow directly to ground from the low potential side of the unit under
test, but flows through the currentmeter first and then to ground.
The connection to be made is (1) connect the low potential side of the unit under test directly to the
Return post (“RTN”) and (2) connect the jumper clip between the Guard (“GRD”) and Ground (“GND”)
posts. (NOTE: Ensure the Ground (“GND”) post is grounded.)
CAUTION
If the test specimen is not fully isolated from ground, the current meter will either not work, or not
display accurate current readings, and this mode should not be used.