Michell Instruments Easidew Online, Руководство пользователя

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Easidew Online User’s Manual
Michell Instruments 31
OPERATION
3.3.4 Re-Transmitted Output Current Range Set-Up
P
P
SET
SET
SET
Main
Disp l ay
De f a ul t setting
0001=4 to 2 0 mA
N ew setting
0000=0 to2 0 mA
Figure 26
Con fi gure Analog Output
The Easidew Online is provided with an
analog current loop output module which
buffers and re-transmits the current loop
input signal from the dew-point transmitter.
By default, the re-transmission output is set
as a 4-20 mA current loop (to exactly follow
the input signal, i.e. 4 mA in, 4 mA out).
For certain system processes, a 0-20 mA
current loop output may be required. The
set-up method is as follows:
Figure 26 shows the operational key
sequence.
To change output from 4-20 mA to 0-20
mA:
1. Press the
P
key once, the display will
read
tECH
.
2. Press the
SET
key and the display will
fl ash between
ConF
and
PinP
.
3. Press the

key and the display will
fl ash between
out1
and
ConF
.
4. Press the
SET
key to display
oAt1
.
5. Press the

key once to display a
fl ashing 4 digit number. For the default
setting (4-20 mA) this will be 0001.
6. Press the

key once to change the
display to 0000. This selects the re-
transmission output to be 0-20 mA.
7. Press the
SET
key to accept the new
value. The output current loop is now
0-20 mA. The display will fl ash between
out1
and
ConF
.
8. Press the
P
key once to return to the
main dew-point temperature display.
Note: The transmitter current loop output signal is now scaled at 6 mA per °C
input, while the transmitter input remains scaled at 7.5°C per mA.