Kikusui PBZ20-20, User Manual

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30
PBZ
Connecting the Load
Using the PBZ in Parallel Operation or with Fast Responses
p. 81
When you use the PBZ in parallel operation or with a fast response setting, you must wire the
load and configure the response setting correctly and reduce the inductance. If these
conditions are not met, the PBZ may oscillate or become unstable.
Load cables and inductance
Load cables have inductance L. If current I changes quickly, a large voltage is induced on
both ends of the cable. This voltage is applied to both the PBZ and the load. The load cable’s
inductance L and voltage E that is induced according to the changes in current I (hereafter
referred to as the induced voltage) are expressed as follows:
How to reduce the effect of wiring
p. 81
• If fast transient response is not required, increase the response setting.
The value of

I /

T is reduced, so even if you can’t reduce the load cable’s inductance,
you can reduce the induced voltage.
p. 142
• When you use the PBZ in parallel operation, use the parallel operation kit.
• Use the shortest cables possible to wire the load, and twist them.
• You can further reduce the effect of wiring by using busbars instead of cables. Arrange
the busbar connected to the COM terminal parallel to the busbar connected to the OUT
terminal, and connect the load as close to the PBZ as possible.
Capacitive and Inductive Loads
p. 37 , p. 81 ,
p. 60
Oscillation may occur when the PBZ is connected to a capacitive load in CV mode or when
the PBZ is connected to an inductive load in CC mode. To remedy this problem, increase the
response setting or use the soft start and soft stop features.
See
Load
OUTPUT
Chassis
terminal
OUT
COM
PBZ
L
I
E = L × (
Δ
I/
Δ
T)
E: The induced voltage
L: The wiring inductance
Δ
I: The change in current
Δ
T: The duration of time over
which the current changes
E
• Generally, a cable’s inductance is 1 µH per meter of cable. If 2 meters of cable are used to
wire the load (the total length of the cables that are connected to the OUT terminal and the
COM terminal) and the current change is 10 A/µs, the induced voltage is 20 V.
See
See
See