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

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 User  Connections  59
 Connecting Series 664xA and 665xA Power Supplies To The Load
 
 
 
€ Output Safety Cover
 
ó + Output Terminal
 
ì - Output Terminal
 
öSignal Common
 
ú Output Sense Switch
 
÷ Analog Connector
 Figure 4-3a. Series 664xA and 665xA Rear Panel Output Connections
 
 Output Isolation
 The output of the power supply is isolated from earth ground. Either output terminal may be grounded, or an external
voltage source may be connected between either output and ground. However, both output terminals must be kept within
 
±
 240 Vdc of ground. An earth ground terminal is provided on the rear panel for convenience, such as grounding wire
shields.
 
 
 The earth ground terminal on the rear panel is a low-noise signal ground for convenience only. It is
not designed to function as a safety ground.
 
 Load Considerations
 
 Capacitive Loads
 
 Effect on the Output Circuit. In most cases, the power supply will continue to be stable with additional external load
capacitors (see the following table for recommendations). 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. If you need help in solving a stability problem, contact an Agilent service engineer
through your local Sales and Support Office (see end of this guide).
 
 Series 664xA/665xA Power Supplies, Maximum External Capacitance (
µ
F)
 6641A
 6642A
 6643A
 6644A
 6645A
 6651A
 6652A
 6653A
 6654A
 6655A
 40,000
 20,000
 12,000
 7,000
   3,000
 100,000
 50,000
 30,000
 18,000
   8,000
 
 If the power supply output is rapidly programmed into capacitive loads, the supply may momentarily cross into CC mode.
This extends the CV programming time and limits the maximum slew rate to the programmed current divided by the total
internal (see the following section “Inductive Loads”) and external capacitance. These momentary crossovers into CC mode
will not damage the supply.
 
 Effect on the OVP Circuit. The OVP circuit is designed to discharge fully-charged capacitances up to a specified limit for
each model. These limits are as follows: