Generation
25
Note
• When outputting, if you change the generation function, generation range, or polarity (only for
current generation), output turns off automatically.
• The resistance generation of this instrument employs an "active impedance" scheme in order to
provide a dummy resistance. This scheme generates a DC voltage appropriate for the current being
measured that is supplied by a resistance meter such as a multimeter. The scheme, therefore, can
generate correct DC voltages only for the resistance meter used in the measuring method shown in
the figure on the previous page (i.e., the value of the supplied current being measured varies
depending on the range of resistance generation. For further details, see the specifications of
resistance on page 51). Note that connecting a low-impedance device (e.g., a voltage source,
capacitor, or resistor) to the output during resistance generation may cause oscillation.
• In the case of the resistance generation function, it takes 10 ms in a 500
Ω
range (refer to the
specifications for other ranges) for the instrument-detected resistance measurement current to
settle within the given accuracy range. This means that the connecting time must be no less than
10 ms where a device that operates by electrically switching its signal input circuit is used.
• Providing any different type of setting with the [ZERO CLR] and [NEXT ENTER] keys during
resistance generation will abort the generation.
• Providing any different type of setting with the [ZERO CLR] and [NEXT ENTER] keys when the
generation function is either TC, RTD, FRQ, or PULSE will change the function to DCV.
Output Limiter
If the load current when generating a voltage of 1 or 10 V range or the load voltage
when generating a current of 20 mA range exceeds the maximum value in the
specifications, the protective limiter turns output off. To recover the output, correct the
load to a normal state and press the [SOURCE ON] key to turn output on.
Current sinking function
This allows drawing the specified value of the current from an external voltage source
in the direction of the Hi terminal.
CA100
Hi
Lo
Ix: Specified value of current
Ix
To use the function follow the procedure below:
1
Turn off the external power supply (up to 28 V).
2
Connect the external power supply to the output terminal on the instrument.
3
Select [DCA] using the [FUNCTION] key, set the polarity to "-" using [+/-], and
specify the output value.
4
Turn on the external power supply and press the [SOURCE ON] key to turn on
output.
Note
• The current-generation function of the CA100 may result in an unstable output if the CA100 is
connected to a positioner or electro-pneumatic converter having a large input inductance
component. Make sure the input inductance component of the equipment to be connected is no
greater than 100
µ
H.
• If the equipment’s input inductance component is unknown, connect the CA100 to the equipment
as shown below, and measure the generated current. If the reading does not stabilize or an
accuracy error results at that point, the input inductance component is likely to be greater than
100
µ
H.
Hi
Lo
Lo
mA
Hi
Lo
CA100
SOURCE
(DC mA)
MEASURE
(DC mA)
Input source:
Equipment such as a
converter
• If the equipment’s input inductance component is too large, connect a 200-
Ω
resistor and a 1-
µ
F
capacitor to the CA100’s output, as shown below. This setup makes it possible to connect an input
having an inductance component of up to 3 H to the CA100.
(This RC circuitry is available as an accessory part numbered 990 20.)
Free Datasheet http://www.datasheet-pdf.com/