power supply impedance at the load at high frequencies. However, the capacitor must be chosen with care if power supply oscillation is to be avoided, since any capacitor resonances or other tendency toward high impedance within or near the bandpass of the power supply regulator will reduce loop stability. It is therefore common in extreme remote sensing applications to remove Co from the power supply and use it as Co'.

Proper Current Limit Operation

Check for proper current limiting operation while the power supply is connected in the system for remote sensing. With some power supply designs, the resistance of one of the current carrying leads adds to the resistance used for current limit monitoring, thereby reducing the threshold value at which current limiting begins. The current limit value should not change significantly while shorting -S to -OUT and +S to +OUT at the power supply. If it does, refer to the instruction manual for corrective adjustments, or contact the manufacturer.

LOAD CONNECTIONS FOR TWO OR MORE POWER SUPPLIES

The extension of the preceding single power supply concepts to multi-power supply systems (Figure 53) is simple and direct, requiring only the application of the following additional rules.

Figure 53. Load Connections for Multiple Power Supplies

DC Distribution Terminals

There must be only one point of connection between the dc outputs of any two power supplies in the multiple

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Agilent Technologies 90B manual Proper Current Limit Operation, Load Connections for TWO or More Power Supplies