2 - General Information
Figure 2-2. Constant Resistance Mode
Immediate Resistance Level
The resistance level can be set at the front panel or via the GPIB (RES command). If the CR mode is active, the new setting immediately changes the input at a rate determined by the voltage or current slew setting (see description below). If the module is not in the CR mode, the new setting is saved for use when the mode is changed to CR.
Triggered Resistance Level
A resistance level can be preset (stored in the electronic load) allowing the input to be updated when a trigger is received instead of immediately as described above.
If the CR mode is active, 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 RES:TRIG command is sent.
Transient Resistance Level
The transient resistance level can be set at the front panel 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.
Slew Rate
The resistance slew rate determines the rate at which the input resistance to a module changes to a new programmed value. Resistance slew rates are programmed in ohms per second. Slew rates can be set at the front panel or via the GPIB (RES:SLEW command). The programmed slew rate remains in effect for the immediate, triggered, and transient level changes previously described.
Constant Voltage (CV) Mode
In this mode, the module will attempt to sink enough current to control the source voltage to the programmed value (see Figure
Ranges
Voltage may be programmed in either of two overlapping ranges, a low range and a high range. The low range provides better resolution at low voltage settings. The range can be set at the front panel or via the GPIB
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