Kikusui PLZ-4W Series, User Manual

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PLZ-4W Appendix A-13
We assume that the overcurrent protection (OCP) setting I
OCP
is greater than cur-
rent I
N
at point N and denote the voltage of the battery as V
M
. In CR mode, if the
resistance is decreased (R
M1
→ R
M2
→ R
N
) to increase the input current (load cur-
rent), the operating point moves along segment MN (M
1
→
M
2
→
N).
When the overpower protection (OPP) setting is P
N
, the OPP trips when point N is
reached.
At this point, two types of operation are available on the PLZ-4W depending on the
protection action setting of the OPP.
If Protect Action is set to LOAD OFF, the load is turned off.
If protection action is set to LIMIT, the PLZ-4W sinks current as a constant power
load at point N. Even if you attempt to increase the current by decreasing the resis-
tance, the current is limited at point N. If you decrease the current by increasing the
resistance, the OPP is cleared. The PLZ-4W returns to CR mode, and the operating
point moves along segment MN.
Table A-8 OPP action (protect action)
If the overpower protection (OPP) setting is P
N1
, the OPP does not trip as the resis-
tance is decreased to increase the current. Consequently, the operating point reaches
point S.
Here, the operation mode is CV. The voltage is
fi xed to voltage V
Q
set in advance.
In this case, the operating point moves along segment QS. The current is determined
by the battery voltage and its internal resistance.
■
Transition of the operating point: Overcurrent protection
(OCP)
Fig. A-16 Transition of the operating point in CR+CV mode (OCP trip
point)
Point N
LOAD OFF
Turns off the load (stops the current fl ow).
The PLZ-4W no longer operates as a load.
LIMIT
CR mode ends. OPP continues, and the PLZ-4W
sinks current as a constant power load.
Input current [A]
Input
voltage [V]
Log scale
V
M
V
Q
Q
S
Constant current line
(OCP setting)
Constant voltage
line
(Constant voltage
setting)
Operating area
OCP trip point
OPP setting
M
I
OCP
I
OCP1
M
1
M
2
R
M1
R
M2
R
T
Constant resistance line
(Constant resistance settings: R
M1
, R
M2
, and R
T
)
T