YOKOGAWA CA71 HANDY CAL, Руководство пользователя

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4-6
IM CA71-E
4.2.4 Using As 24-V Loop Power Supply
A maximum load current of 22 mA can be drawn from the calibrator
by selecting the 30 V range and setting the sourced voltage to 24 V.
With this function, you can use the calibrator as a loop power supply
in place of the distributor in a two-wire loop, as shown in the following
figure. Thus, you can measure a 4-20 mA current signal.
Using the supplied terminal adapter (P/N: 99021) makes it easy to
wire the calibrator for this application.
NOTE
Since the function discussed above requires a significant amount of
DC current (22 mA), operation on batteries will reduce the battery life
considerably.
To avoid this problem, operate the calibrator on the AC adapter.
In this application, no source output other than 24 V can be taken at
the same time.
CA71
AC adapter
24V
4-20 mA
Input
A
Two-wire
transmitter
L mA H L
MEASURE SOURCE
24 V output
Using As a Loop Power Supply
4.2 Sourcing DC Voltage, DC Current or SINK Current Signal