Operation Overview 23
Triggered Resistance Level
The resistance level can be preset (stored in the Electronic Load) allowing the input level to change when a trigger is
received instead of immediately as previously described. The resistance level can only be preset via the GPIB (RES:TRIG
command). The preset capability is not available at the front panel.
If the CR mode is the active mode, the preset resistance level will become the actual value and the input will be updated
when a trigger occurs. If the CR mode is not the active mode, the preset resistance level will become the actual value when
a trigger occurs but there will be no effect on the input until the CR mode becomes active. Once a level is triggered,
subsequent triggers will have no effect on the input unless another CURR:TRIG command is sent.
Transient Resistance Level
The transient resistance level can be set at the front panel (
, and ENTRY keys) or via the GPIB
(RES:TLEV command). The transient level and the main level are used in transient operation, which is described later in
this chapter. In the low resistance range, the transient level must be set to a higher resistance value than the main level.
However, in the middle and high resistance ranges, the transient level must be set to a lower resistance value than the main
level.
Slew Rate
Slew rate in resistance mode is not programmed in ohms/second. In the low resistance range, slew rate is programmed in
volts/second. Whatever value is programmed for the voltage slew rate is also used for the low resistance range.
In the middle and high resistance ranges, slew rate is programmed in amps/second. Whatever value is programmed for the
current slew rate is also used for the middle or high resistance ranges.
Constant Voltage (CV) Mode
In this mode, the load will attempt to sink enough current to control the source voltage to the programmed value (see Figure
2-3). The load acts as a shunt voltage regulator when operating in the CV mode. The CV mode can be set
at the front panel (
, and keys) or via the GPIB (MODE:VOLT command). The CV mode
parameters are described in the following paragraphs.
Range
Voltage mode has only one range
Figure 2-3. Constant Voltage Mode