Section 4: Sourcing and measuring
2470 High Voltage SourceMeter Instrument Reference Manual
4-18
2470-901-01 Rev. A /
May
2019
The zero mode is ideal for passive devices such as resistors. In most cases, it can also be used with
energy storage devices such as capacitors and inductors. This mode will discharge capacitors under
test, and remove the charge from semiconductor junctions.
Guard output-off state
Use the guard output-off state when you are measuring a load that uses an active source.
When the guard output-off state is selected and the output is turned off, the following actions occur:
•
The measurement sense is changed to 2-wire
•
The current source is selected and set to 0 A if the source is set to current (amps); otherwise, the
output remains a voltage source when the output is turned off
•
The voltage limit is set to 10% full scale of the present voltage range
Output-off states and inductive loads
To protect the instrument from inductive energy, you may need to install a spark gap across the HI
and LO terminals. The instrument does not have internal spark gap protection.
Setting the output-off state
Before setting the output-off state, set the source function. The output-off state is stored with the
source function. If you change the source function, the output-off state changes to the last state you
set for that function.
Using the front panel:
1.
Press the
MENU
key.
2.
Under Source, select
Settings
.
3.
Set
Output Off
to the appropriate setting for your application.
4.
Select
HOME
to return to the operating display.
Using SCPI commands:
To set the output-off state to normal, send the command:
:OUTPut:SMODe NORMal
To set the output-off state to zero, send the command:
:OUTPut:SMODe ZERO
To set the output-off state to high impedance, send the command:
:OUTPut:SMODe HIMPedance
To set the output-off state to guard, send the command:
:OUTPut:SMODe GUARd
