NOVUS TxMiniBlock - Manual (Page 2)

TxMiniBlock Transmitter
NOVUS AUTOMATION 2/2
3. Filtration Optimization: Filters the measurements made by the
transmitter eliminating interferences from the electrical system that feeds
the process.
4. Sensor Failure: Establishes the behavior of the output when problems are
presented by the sensor. When Minimum is selected, the output current shifts
to < 4 mA (down-scale), typically used in refrigeration. When Maximum is
selected, if shifts to > 20 mA (up-scale), typically used for heating.
5. Zero Correction: Corrects minor errors presented by the transmitter, for
example, when the sensor is changed. See item Operation in this manual.
6. Transmitter Information: In this field, there are data that identify the
transmitter. This information must be informed in any consultation with the
manufacturer.
7. Read Configuration: When pressed, this allows one to read the
configuration on the transmitter connected.
8. Send Configuration: When pressed, this allows one to send the
configuration to the transmitter connected.
Note: If, on the purchase order, the user does not define a specific
configuration, the following configuration will be set:
• Pt100 sensor, range 0 to 100 °C, 0 °C zero correction.
• Filter to 60 Hz and maximum output for sensor failures.
4 MECHANICAL INSTALLATION
The TxMiniBlock transmitter is suitable to be installed on heads.
Figure 04 – Transmitter dimensions
5 ELECTRICAL INSTALLATION
Polyamide housing for the terminals.
Section of the wire: 0.14 a 1.0 mm².
Recommended Torque: 0.8 Nm.
RECOMMENDATIONS FOR INSTALLATION
• Input signal conductors should run away from power and contactor
wires, if possible, in grounded conduits.
• The instruments must be powered by a suitable network for
instrumentation.
• System failure should always be taken into account when designing a
system to avoid irreversible damage to equipment or people. Installing
RC filters (47 Ω and 100 nF, in series) is strongly recommended at
contactor coils or any other inductors.
ELECTRICAL CONNECTIONS
Figure 05 below shows the transmitter wiring. Terminals 1, 2 and 3 are used
for sensor input. For 2-wire Pt100, terminals 2 and 3 shall be connected
together. The LOAD represents the input shunt of an instrument measuring
the 4-20 mA current loop.
The figure below shows the electrical connections required. Terminals 1, 2
and 3 are used for the Pt100 input. For 2-wire Pt100, terminals 2 and 3 must
be interconnected.
Figure 05 – Transmitter electrical connections – Pt100
The LOAD represents the input shunt of an instrument measuring the 4-20
mA current loop (indicator, controller, recorder, etc).
6 OPERATION
The sensor input is factory calibrated. Recalibration in the field is not
recommended, but it can be accomplished through the TxConfig software.
Contact the factory for the calibration procedure.
When necessary, fine adjustments to the transmitter output current can be
accomplished directly at the transmitter. To do so, short circuit transmitter
terminals 1 and 4. After 2 seconds, the output current starts to increase
gradually until it reaches 0.8 mA above the initial value. After reaching that
value, it drops to 0.8 mA below the initial value, increasing gradually again.
The user must monitor the output current and open the circuit when the
current reaches the desired value.
The offset correction can also be accomplished through the TxConfig
software. The TxConfig interface can be connected to the transmitter while it
is operating in the process. See in Figure 03 the Zero Correction field in the
main screen of the TxConfig software.
The user must choose the sensor span most suitable to the application. The
maximum and minimum sensor spans are limited in the TxMiniBlock and in
the TxConfig software. The user can configure any value within those two
limits.
It is important to note that the accuracy of the transmitter is always based on
the maximum range of the Pt100 sensor, regardless of the configured span. .
Example:
• Pt100 maximum span = 850 °C; 0.2% accuracy.
• Maximum error = 1.7 °C (0.2 % de 850 °C)
The error is the same no matter if total span is used (-200 to 650 °C) or a
narrower user-defined span is used, like 0 to 100 °C.
Note: When using a Pt100 simulator, make sure the TxMiniBlock’s Pt100
excitation current (0.20 mA) is compatible with the simulator specification.
7 SAFETY INFORMATION
Any control system design should take into account that any part of the
system has the potential to fail. This product is not a protection or safety
device and its alarms are not intended to protect against product failures.
Independent safety devices should be always provided if personnel or
property are at risk.
Product performance and specifications may be affected by its environment
and installation. It’s user’s responsibility to assure proper grounding,
shielding, cable routing and electrical noise filtering, in accordance with local
regulations, EMC standards and good installation practices.
8 SUPPORT AND MAINTENANCE
This product contains no serviceable parts inside. Contact our local
distributor in case you need authorized service. For troubleshooting, visit our
FAQ at www.novusautomation.com .
9 LIMITED WARRANTY AND LIMITATION OF LIABILITY
NOVUS warrants to the original purchaser that this product is free from
defects in material and workmanship under normal use and service within
one (1) year from the date of shipment from factory or from its official sales
channel to the original purchaser.
NOVUS liability under this warranty shall not in any case exceed the cost of
correcting defects in the product or of supplying replacement product as
herein provided and upon the expiration of the warranty period all such
liability shall terminate.
For complete information on warranty and liability limitations, check
appropriate section in our web site: www.novusautomation.com .