l
For 40V, 60V, 80V, 120V and 160V N6900 models without relay disconnect option
760 or 761, all outputs must be turned off on all series-connected units before AC
power is turned off on any of the units.
l
Always turn the outputs on and off together. It is recommended to use the digital
I/O pins to couple the output turn-on/turn-off transitions between the units as
described under
.
l
Always program identical voltage settings on all units, and synchronize the
voltage up and down programming across units.
l
Set the
to identical values on all series-connected units.
l
Set the
to its most negative value, thus allowing each instru-
ment maximum capability to protect itself and balance the voltages.
l
Couple the output protection systems of the series-connected units as described
under
Fault/Inhibit System Protection
. This prevents uneven voltage sharing
between units if one or more shut down due to a fault condition.
l
If the current Sharing cables are connected, do not enable current sharing under
any circumstances or the power supply may be damaged. Refer to
to disable. To protect the unit in case the current sharing function is acci-
dentally enabled, you should physically disconnect the current sharing cable
from the back of the unit.
l
Do not use the N7909A power dissipator when connecting power supplies in
series. Series connections are not allowed if the power supplies are being used to
sink current.
Load, Sense, and Diode Connections
The following figure shows how to connect three units in series. Note the following recommendations:
l
To guarantee protection from reverse currents in all cases, it is recommended to always connect a
series diode in line with your load as shown.
l
Install the units relatively close to each other in a stacked configuration.
l
Keep the wiring from the power supplies to the load as short as possible and twist or bundle the
leads to reduce lead inductance and noise pickup. The goal is to always minimize the loop area or
physical space between the + and - output leads from the power supply to the load.
l
If the series diode is being used, connect the sense leads as shown below. Without the diode, con-
nect the +s lead directly to the load.
2 Installing the Instrument
80
Keysight N6900/N7900 Series Operating and Service Guide
Summary of Contents for N6900 Series
Page 1: ...Keysight Advanced Power System N6900 N7900 Series Operating and Service Guide...
Page 2: ......
Page 63: ...1 kW Models Keysight N6900 N7900 Series Operating and Service Guide 63 1 Quick Reference...
Page 64: ...2 kW Models 1 Quick Reference 64 Keysight N6900 N7900 Series Operating and Service Guide...
Page 78: ...2 Installing the Instrument 78 Keysight N6900 N7900 Series Operating and Service Guide...
