DewPro<Superscript>® MMR31 Installation & Operation Manual
25
Chapter 4. Optional Display/User Interface
4.4.4
Temperature Measurement Functions
Table 8:
Function
Location
Description
Displaying the
Measured
Temperature
VH 40
Selecting this location displays the present process temperature. The unit of measure
(°F/°C) is the unit selected in location
VH41
(see below).
Selecting the
Temperature
Unit
VH 41
This allows the user to select either °F or °C as the temperature measurement unit to be
displayed in location
VH 40
. Setting this location to
0
selects °C, and setting to
1
selects °F. (Default: 0)
Setting the
Temperature
Output Range
VH 45
VH 46
These locations specify the range of temperatures corresponding to the 4–20 mA range
of current output #2. The range of values for both locations is from
–15
and
+85
. The
output range is always specified in °C, regardless of the display units selected.
Loop #2
at Fault
VH 47
This location specifies the condition for current output #2 when a fault is detected in the
temperature measurement circuitry. The available options are:
0 = –10% (3.6 mA)
1 = 110% (22 mA) (Default)
2 = Hold at previous level
Calibrating the
Current Output
VH 78
VH 79
These locations are used to calibrate the 4 mA and 20 mA hardware settings of the
temperature output current loop. This output comes calibrated from the factory and
should not normally need adjustment. To check the setting, connect an ammeter in
series with the negative (
–)
power terminal for loop #2. Move to matrix location
VH 78
.
The output will automatically change to the 4 mA setting. Adjust as necessary using the
+
and
–
keys. Move to location
VH 79
. The output will automatically change to the 20 mA
setting. Again, adjust as necessary. Move to any other matrix location to return the
output to normal operation.
If the matrix input is locked (
VH 89
), the calibration values are displayed, but the current
output is unaffected.