Kikusui PBZ20-20, User Manual

Page: 56 / 170

56
PBZ
Using External Control Signals
Using External Resistance
You can control the internal signal source’s DC signal by changing the reference voltage’s
voltage-divider ratio through the use of external variable resistors. In CV mode, you can
control the voltage. In CC mode, you can control the current. The output is equal to the sum
of the value that is determined by the external resistance and the DC values that are set from
the panel and remote control.
Connecting an external resistor
Connect an external resistor (Rext) as shown in the following figure. The arrow represents the
wiper.
For Rext, use a resistor that is rated at approximately 10 k

, 1/2 W or greater, that has a low
temperature coefficient, and that will change little over time. Examples of such resistors are
metal film or wire wound resistors. To reduce the influence of noise on the output, connect a
two-wire shielded cable or a twisted pair cable across Rext, and connect the resistor so that it
is as close to the PBZ as possible. If the wiring between the PBZ and the resistor is long, it
becomes easy for noise to influence the operation of the PBZ. Even if you use wires that are
designed to suppress noise, the PBZ may not operate properly.
The relationship between the external resistance and the output
p. 55
The voltage across the wiper that is in contact with the external resistance and J1 pin 24 is
Vext, which is used to control the voltage. The relationship between Vext and the output is the
same as when you are using an external voltage.
OUTPUT
Chassis terminal
SENSING
PBZ
J1
OUT
COM
OUT
COM
Two-wire shielded cable
or a twisted pair cable
25
26
1
2
23 21
J1
23
25
21
Rext
10 k
Ω
The pin numbers are the socket numbers.
This is the PBZ J1 connector pinout.
Vext
24
• If you are switching between fixed resistors to control the PBZ, use a short-circuit type or
continuous-type switch.
See