144
PLZ-4WH
Operating Area
How constant voltage (CV) mode works
In CV mode, the PLZ-4WH sinks current so that the voltage at the load input end of the PLZ-
4WH is constant.
Constant voltage mode operation
When the PLZ-4WH is used in constant voltage (CV) mode, it operates as a constant-voltage
load (shunt regulator) as shown in the figure below. When V1 is greater than V, the input
voltage V is kept constant even when the input current I varies. Current does not flow when
V1 is less than or equal to V. In the figure below, R
1
is the internal resistance of the constant-
voltage power supply. The PLZ-4WH may operate unstably if R
1
is low.
Transition of the operating point: overpower protection (OPP)
In this example, we will assume that the PLZ-4WH is being used in constant voltage (CV)
mode to test the load characteristic of a constant-voltage power supply.
When the overcurrent protection (OCP) setting I
OCP
is greater than current I
N
at point N, the
voltage of the constant voltage power supply is V
M
. Current will not flow if the PLZ-4WH
voltage V
M0
is greater than V
M
. If the voltage of the PLZ-4WH is decreased so that V
M0
is
less than V
M
, current starts flowing. If the voltage is decreased further (V
M1
→
V
M2
→
V
N
) so
that the input current (load current) increases, the operating point moves along segment MN
(M
1
→
M
2
→
N).
When point N is reached, overpower protection (OPP) is activated. At this point, one of two
types of operations occurs, depending on the protection action setting for OPP.
If the protection action is set to LOAD OFF, the load turns off.
If the protection action is set to LIMIT, the PLZ-4WH sinks current as a constant-power load at
point N. Even if you attempt to decrease the voltage, the current will not increase beyond
point N. If you increase the voltage, overpower protection (OPP) is cleared. The PLZ-4WH
returns to constant voltage (CV) mode, and the operating point moves along segment MN.
PLZ-4WH Series
Constant-voltage
power supply
I
V
R
1
The voltage is constant even
when the current varies.
V
1
Current I
Voltage
V
0
Input current [A]
Input voltage [V]
Logarithmic scale
V
M
V
M0
V
N
V
M2
V
M1
Constant power line
(constant voltage setting)
Constant voltage line
Operating area
OPP activation point
(OPP setting)
M
N
I
N
I
OCP
M
1
M
2
Содержание PLZ1004WH
Страница 13: ...Installation and Preparation This chapter describes how to unpack and prepare this product before you use it 1 ...
Страница 28: ...28 PLZ 4WH Remote Sensing ...
Страница 29: ...Basic Functions This chapter explains the operations for each operation mode and other basic functions 2 ...
Страница 47: ...Advanced Operations This chapter explains ABC preset memory setup memory protection functions and the menu 3 ...
Страница 61: ...Sequences This chapter explains the sequence function Sequences 4 ...
Страница 83: ...External Control and Parallel Operation This chapter explains external control and Parallel Operation 5 ...
Страница 115: ...Maintenance This chapter describes the maintenance procedures including cleaning inspection and calibration 7 ...
Страница 127: ...8 Specifications This chapter contains the specifications and gives the dimensions of the PLZ 4WH ...
Страница 137: ...Appendix A Operating Area B Sequence Program Creation Table C Options ...