Kikusui PWX1500H, Руководство пользователя

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PWX
69
3
External Con
trol
Controlling the Output Current
This section explains how to control the output current using an external voltage (Vext) or an
external variable resistor of approximately 10 k
Ω (Rext).
Control using an external voltage (Vext)
p.46
To use an external voltage (Vext) to control the output current, set the CC control using an
external voltage or an external resistance in the CONFIG settings so that external voltage con-
trol is enabled (CF05: on).
The output current (Io) varies in the range of 0 to the rated output current (Irtg) when the
external voltage (Vext) is changed in the range of 0 V to 5 V (CF07: Lo) or in the range of 0 V
to 10 V (CF07: Hi).
External voltage source (Vext) connection
Connect a low-noise, stable voltage
source to Vext. The noise in Vext is
multiplied by the amplification factor of
the PWX series and appears in the
output. Therefore, the output ripple
noise may not meet the specifications
of the PWX series.
To reduce the influence of noise on the
output, connect a 2-core shielded wire
or a twisted-pair wire across Vext, and
keep the wire as short as possible. If
the wiring between the PWX series
and the external contact is long, it becomes easy for noise to influence the operation of the
PWX series. Even if you use cables that are designed to suppress noise, the PWX series
may not operate properly.
WARNING
Risk of electric shock.
• The insulation of Vext or Rext and the connected cable must be greater than or equal
than or equal to the isolation voltage of the PWX series.
For the isolation voltage of each model, ”Specifications” on page 93.
• When using shielded cables for the connection, protect the uncovered sections of
the shielded cable by using insulation tubes whose withstand voltage is greater than
the PWX series isolation voltage.
See
External voltage (Vext) 0 V to 5 V (CF07: Lo) External voltage (Vext) 0 V to 10 V (CF07: Hi)
Io = Irtg × Vext/5 (in A)
Vext = 5 × Io/Irtg (in A) Io = Irtg × Vext/10 (in A)
Vext = 10 × Io/Irtg (in A)
CAUTION
• The signal cable may burn out. Do not connect the Vext output, that is, leave it floating.
Risk of damage to the product.
• Pay careful attention to the polarity of Vext.
• Do not apply a voltage of 10.5 V or greater, or a reverse voltage across the external voltage
control pins.
• When using the optional isolated analog interface, do not connect anything to pin 21
(IPGM) of the J1 connector.
2-core shielded wire or
twisted-pair wire
Vext
+
–
Output terminals
J1
21
23
PWX