Moore Industries TDY, Руководство пользователя

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TDY
Demand Moore Reliability 19
Disabling Broken Wire Detection
One of the premier features of many of Moore
Industries’ temperature transmitters is our Total
Sensor Diagnostics
®
system. During operation, the
TDY sends random micro-amp pulses through input
wiring to check for broken wiring or a burned out
sensor.
Working with a Millivolt Input
When the transmitter is connected to a PC, the “TDY
Status” section of the Main Configuration screen
displays the message “Broken Wire” whenever
problems are detected on the input, and the
transmitter itself drives its output upscale or
downscale.
This can cause problems for some types of millivolt
calibrators and input sources. To permanently
disable this feature when the TDY is working in a
millivolt input configuration, set the “Broken Wire”
radio button in the center-right section of the
Configuration Screen to OFF.
Working with a Thermocouple or RTD Input
Total Sensor Diagnostics can also cause problems
with some types of temperature calibrators. It is not
possible to disable the feature by setting the “Broken
Wire” radio button to OFF, as with millivolt inputs.
Instead, when working with thermocouple or RTD
inputs, set the “Calibration” radio button in the lower-
left area of the Configuration Screen to “Calibration
Mode”. This temporarily disables Total Sensor
Diagnostics.
Note:
It is not possible to set a TDY transmitter into
Calibration Mode (Sensor Diagnostics OFF)
permanently. The “Calibration Mode” setting remains
in effect only until a Configuration File is downloaded
to the transmitter.
Working with a Configuration File
Also, when working with a Configuration File, it may
be necessary to turn off Total Sensor Diagnostics
in order to complete the settings for one or another
aspect of transmitter operation. To do this, click on the
“Stop BW” (Stop Broken Wire Detection) button when
it is active on the bottom of the screen.
Setting Miscellaneous Functions—
Engineering Unit Readout, Input
Filtering, Upscale or Downscale
Drive, and Broken Wire Detection
There are several “radio buttons” on the TDY
Configuration Program Main Screen that control
ancillary transmitter functions. It is not necessary to
have a transmitter hooked up to the PC in order to set
these parameters and save them in a Configuration
File.
Setting Engineering Unit Readout
When a temperature sensor is designated as the input
to the transmitter, the radio buttons for “Degree” are
enabled.
Use this setting to have the Configuration Program
calculate the Centigrade or Fahrenheit temperature for
readout in the “Status” area of the screen whenever
the PC is being used to monitor the input from the
connected sensor and from the display if the
“Input” option in the “Display” section is selected.
Setting Input Filtering
Use this radio button setting to filter out noise on the
power to the transmitter.
Choosing Between
Upscale and Downscale Drive
The TDY transmitter can be configured to provide a
special warning, using its output, of a breakdown in
its connected sensor or sensor wiring. Use this radio
button setting to configure the transmitter to drive its
output either up to 24mA or down to 3.3mA when a
sensor or sensor wiring failure is detected.
Note:
There is a difference between the available
Full Scale output setting and the Upscale Drive,
and between the available zero scale output setting
and the Downscale Drive:
The TDY transmitter will only output 24mA or 3.3mA
(as configured) in the event of a sensor or sensor
wiring failure (upscale/downscale drive).
If sensor input drops below the rated range, output
drops to a minimum of 3.8mA. If sensor input rises
above the rated range, output rises to 21.4mA.
This allows the user to distinguish between an input
failure and an input over or under-range condition.