Michell Instruments MDM300 I.S, Руководство пользователя

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MDM300 I.S. User’s Manual
Michell Instruments 15
INSTALLATION
2.6.1 Set up External Sensor Interface
After connecting the Easidew I.S. transmitter, the following parameters must be defined:
Switch on the instrument and set the required
DP/TEMP
units to either
°C, °F or K
from
the SETTINGS Menu (refer to Section 3.4.1). Set up the required pressure units.
Using the
EXTERNAL
option from the SET-UP Menu, set up the instrument for an
external Easidew input as follows (refer to Section 3.4.4):
EXTERNAL TYPE
Select
EASIDEW
EXTERNAL ZERO
-100°C (
DP Temp
represented by 4 mA input - can be reset)
EXTERNAL SPAN
20°C (
DP Temp
represented by 20 mA input - can be reset)
USER PRESSURE
Refer to Section 2.6.2. NOTE : Pressure compensation does not
affect the reading of the external sensor.
After completion of the above settings, return to the Main Display. The instrument will
now display dew point from the external sensor in the secondary display area and the
selected units. (Refer to Section 3.4.6 for more information.)
An example is shown below
:
Dewpoint External
°C
-25.7
-26.9
°C dp
Figure 11
Typical External Dew-Point Display
2.6.2 Entering User Pressure
The MDM300 I.S. can be programmed with a pressure to be used in the calculation of
atmospheric equivalent or pressure dew point, moisture content or absolute humidity.
NOTE: Care should be taken to ensure that the entered pressure is correct as
it may have a considerable effect on the measurement.
Using the
EXTERNAL
option in the SET-UP Menu, set a user pressure as follows.
1. Scroll to
USER PRESSURE
.
2. Use the

and

keys to select either
ATM
(for atmospheric pressure) or
the required pressure.
NOTE: The pressure units are selected in the Settings Menu.