American Magnetics 12200PS DC Power Supply (CE-Marked) - Manual (Page 36)

LOCAL OPERATION OPERATING MANUAL
3-2 Release 1.0 (98/07)
3.2.1 Operating Modes and Automatic Crossover (continued)
Constant Voltage Mode Operation
The power supply will operate in constant voltage mode whenever the load current I
L
is less than the current
limit setting I
SET
, or: I
L
< I
SET
(Note: I
L
= V
SET
/ R
L
)
In constant voltage mode, the power supply maintains the output voltage at the selected value (V
SET
) while the
load current I
L varies with the load requirements.
Constant Current Mode Operation
The power supply will operate in constant current mode whenever the load resistance is low enough that the load
current I
L
is equal to the current limit setting I
SET
(Note: V
L
=I
SET
R
L
)
In constant current mode, the power supply maintains the output current at the selected value (I
SET
) while the
load voltage varies with the load requirements.
Automatic Mode Crossover
This feature allows the power supply to automatically switch operating modes in response to changing load
requirements. If, for instance, the power supply was operating in Constant Voltage Mode (I
L
< I
SET
), and the
load changed so that the load current (I
L
) became equal to the current limit setting (I
SET
), the power supply
would automatically switch into Constant Current Mode and the output voltage would vary in response to
changes in load current. If the additional load was subsequently removed so that the load current was again less
than the current limit setting, the supply would automatically return to Constant Voltage Mode.
3.2.2 Shipped Configuration (Local Control Mode)
The factory ships units already configured for local control (front panel) operation. Table 3.2-1 summarizes this
configuration. See Figure 2.3-1 and Figure 2.3-2 for front and rear panel diagrams.
Table 3.2-1 Shipped Configuration (Local Control Mode)
Local Control Configuration Additional References
Use the front panel controls to adjust the output
voltage and current limit settings. (Note: Use the
LOCAL button only when you have a digital
programming interface installed.) Section 3 covers front panel operation. See Section 4
Remote Operation for remote analog programming
procedure(s).
The supply's sense point is at the rear panel J10
sense connector terminals. See Section 2.8 Local and Remote Sensing for how to
change from local to remote sensing.
The over voltage protection (OVP) set point is
adjusted at the front panel to approximately 110% of
rated output voltage. See Section 3.3 Using Over Voltage Protection (OVP)
for the adjustment procedure.
The over temperature shutdown function
automatically resets when activated as determined by
the position of rear panel switch SW1-8. A latch off
setting is also available. See Section 3.6 Over Temperature Protection (OTP)
for more information about switch SW1-8 settings.