142
PLZ-4WH
Operating Area
How constant power (CP) mode works
In CP mode, the PLZ-4WH sinks current so that the power consumed inside the electronic
load is constant.
Constant power mode operation
When the PLZ-4WH is used in constant power (CP) mode, it operates as a constant-power
load as shown in the figure below. When the voltage (V1) of the constant-voltage power
supply increases, the input current (I) decreases so that the power P consumed by the PLZ-
4WH is kept constant (P = V
×
I). In the figure below, P = V
2
×
I
2
= V
3
×
I
3
.
Transition of the operating point: overcurrent protection (OCP)
In this example, we will assume that the PLZ-4WH is being used in constant power (CP)
mode to test the load characteristic of a constant-voltage power supply.
■
Operation on segment AB
If the voltage of the constant-voltage power supply is set to V1 and the power of the PLZ-
4WH is increased (P
1
→
P
2
→
P
B
), thereby increasing the input current (load current), the
operating point moves along segment AB (A
1
→
A
2
→
B).
When point B is reached, overcurrent protection (OCP) is activated. At this point, one of two
types of operations occurs, depending on the protection action setting for OCP.
If the protection action is set to LOAD OFF, the load turns off.
If the protection action is set to LIMIT, the PLZ- 4W sinks current as a constant-current load at
point B. Even if you attempt to increase the input current, the current will not increase beyond
point B. If you decrease the input current, overcurrent protection (OCP) is cleared. The PLZ-
4WH returns to constant power (CP) mode, and the operating point moves along segment
AB.
I
V
0
The power (P) is constant even
when the current and voltage vary.
×
×
PLZ-4WH Series
Constant-voltage
power supply
V
1
Current I
Voltage
V
V
2
V
1
I
1
I
2
V
2
V
1
I
1
I
2
=
=
P
Maximum rated current
Input current [A]
Input voltage [V]
Logarithmic scale
Constant power line
(OCP setting)
Constant current line
Operating area
OCP activation point
(constant power settings: P
1
, P
2
, and P
B
)
B
V
1
V
3
G
A
H
A
1
A
2
P
1
P
2
P
B
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 ...