Agilent Technologies Model 6654A: 3148A-00391 Manuale Utente

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User Connections
 74
 Connecting Series 668xA Power Supplies To The Load
 
 ENERGY HAZARDThese power supplies can provide more than 240 VA at more than 2 V. If the
output connections touch, severe arcing may occur resulting in burns, ignition or welding of parts. Do
not attempt to make connections to live output circuits.
 
 
 
€ Analog Connector
 
ó -Output Bus Bar
 
ì -Local Sense Tap
 
ö + Output Bus Bar
 
ú + Local Sense Tap
 
÷ Signal Common
 A  Option 601 cover required for bench installation
 
 Figure 4-5a. Series 668xA Rear Panel Output Connections
 
 Output Isolation
 
 Except for a high value (>1 M
Ω
) internal bleeder resistor, the output of the power supply is isolated from earth ground.
Either output terminal may be grounded or an external dc voltage source may be connected between either output and
ground. However, both output terminals must be kept within 
±
60 Vdc of ground.
 
 The earth ground terminal located near the output bus bars is a low-noise signal ground for
convenience only. It is not designed to function as a safety ground.
 
 
 Load Considerations
 
 Capacitive Loads
 
 In most cases, the power supply will maintain stability with external load capacitors. However, large load capacitors may
cause ringing in the supply’s transient response. It is possible that certain combinations of load capacitance, equivalent series
resistance, and load-lead inductance will result in instability (see also “Stability” under “Remote Sensing”). If you need help
solving a stability problem, contact an Agilent Service Engineer through your local Agilent Sales and Support Offices.
 
 If the output is rapidly programmed into capacitive loads, the power supply may momentarily cross into CC operation,
thereby extending the CV programming time. When it crosses into CC mode, the supply's maximum slew rate is limited by
the CC loop and is a function of the loop current compensation. This may be optimized for particular compensation. These
momentary crossover situations, which are communicated via the status register, may increase programming times, but will
not damage the power supply.