Novus RHT-WM-485-LCD User manual

NOVUS AUTOMATION 1/6
Transmitters RHT
-WM-485-LCD,
RHT
-DM-485-LCD and RHT-P10-485-LCD
TEMPERATURE AND HUMIDITY TRANSMITTER
–
INSTRUCTIONS MANUAL V1.0x
E
1INTRODUCTION
The RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD
transmitters include high precision and stability sensors for measuring
temperature and relative humidity. They are microprocessed devices and,
therefore, allow being entirely configured through a RS485 interface, using
the Modbus RTU commands. The DigiConfig allows the configuration of all
transmitter features as well as its diagnostic procedure.
The transmitter can be configured or displaying the values of measured
temperature and Relative Humidity or the values of measured temperature
and Dew Point.
1.1 IDENTIFICATION
The identification label is fixed on the transmitter body. Check if the features
described on this label are in accordance with your order.
The RHT-WM-485-LCD and RHT-P10-485-LCD models intended for wall
mounting, while the RHT-DM-485-LCD model comes with a probe tip rod for
installation in ducts or through walls.
The following elements are located at the front side of the transmitter:
Fig. 1 – Transmitter front
Communication Indicator (COM): Indicates when the device is receiving
data from the Modbus network.
Button (Programming): Button used for configuration of the
communication parameters and for screen changing.
Temperature: Value of measured temperature.
Relative Humidity: Value of measured relative humidity.
Fig. 2 – Second transmitter screen
Communication Address: Value programmed for identifying the transmitter
of the Modbus network. Programmable between
1
and
247
.
2SPECIFICATIONS
Operating temperature of
the transmitter
From -40 °C to 70 °C
Sensor and Rod (RHT-DM): See Fig. 3.
Electromagnetic
compatibility EM 61326:2000
Sensor measuring
range
Temperature: -40.0 °C to 100.0 °C.
Relative Humidity (RH): 0.0 to 100.0 % RH.
(No Condensing)
Dew Point: -40.0 °C and 100.0 °C
Measurement accuracy
See Fig. 3.
Note: a small measur
ement error can be
eliminated adjusting the OFFSET parameter of
the software.
Measuring resolution
Temperature: 0.1 °C.
14 bits (16383 levels)
Relative Humidity (RH): 0.1 %.
12 bits (4095 levels)
Response time
Temperature: up to 30 s in slow air movement.
Humidity: up to 8 s in smooth air movement
(20 to 80 % RH).
Sampling interval 3 seconds
Power supply 12 Vdc to 30 Vdc, consumption < 16 mA
Housing Polycarbonate
Protection class
Product appropriate for applications which
require protection class up to IP65.
Electronic module case: IP65; Sensor
capsule: IP40
Dimensions 60 x 70 x 35 mm
DigiConfig software
operation environment
Configuration Software for Windows 98, NT,
2000, XP and Vista.
Menus in Portuguese, English or Spanish.
Configures, reads and exhibits data on the
screen.
Accessories
1.5 m long communication cable is part of the
product or can be purchased separately (PN:
8813099999).

NOVUS AUTOMATION 2/6
2.1 MEASUREMENT ACCURACY AND OPERATIONAL LIMITS OF THE SENSORS
Fig. 3 - Accuracy of humidity and temperature measurement
3MECHANICAL INSTALLATION
The RHT-DM-485-LCD (Duct Mount) model transmitter must be installed
with a flange. This flange is first screwed onto the duct wall, and the
transmitter probe is then inserted into the flange central hole and locked. Fig.
4below shows flange dimensions and holes. Available in stainless steel or
polyamide 6.6.
Fig. 4 - Flange for fixation of the RHT-DM-485-LCD model
The probe is made in stainless steel, with standard lengths of 150 mm or
250 mm.
Fig. 5 – Dimensions of the RHT-DM-485-LCD model
The RHT-WM-485-LCD (Wall Mount) model is designed for wall mounting.
Removing the transmitter cover gives the user access to two bores for fixing
the base, as shown in Fig. 6. The transmitter must be fixed with the
sensor capsule directed downwards in order to assure the specific
accuracy and protection level.
Fig. 6 - Fixing bores and dimensions of the RHT-WM-485-LCD model
Fig. 7 – Dimensions of the RHT-WM-485-LCD model

RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD Transmitters
NOVUS AUTOMATION 3/6
The RHT-P10-485-LCD electronic housing is designed for wall mounting,
while its remote sensor probe is intended for inserting and screwing in a
flange.
Fig. 08 – Probe dimensions
Fig. 09 – Mounting flange
Note: The flange is not bundled with the transmitter. It must be ordered
separately.
4ELECTRICAL INSTALLATION
ELECTRICAL CONNECTIONS
The Fig.10 below shows the necessary electrical connection. The terminals
1, 2, 3 and 4 are intended for connection.
1 - VCC Power supply Black wire
2 + VCC Power supply White wire
3
D1
D
D+
A
Bi-directional data line.
Blue wire
4 D0 D- B
Bi-directional inverted data
line. Brown wire
Fig. 10 – Electrical connections
Fig. 11– M8 Connector Pins
Be careful when connecting the power supply wires to the
RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-
LCD Transmitter. If the positive wire from the power source
is
connected, even momentarily, to one of the
communication connection terminals, the transmitter may be
damaged.
RECOMMENDATIONS FOR INSTALLATION
•Small electric signal conductors must pass through the system plant
separated from the actuating conductors or from high current or voltage
lines, if possible, inside grounded conduits.
•The power supply of the instruments must be provided from a proper
network for instrumentation.
•In control and monitoring applications it is essential to consider what can
happen if any part of the system should fail.
•We recommend the use of RC FILTERS (47Ωand 100nF, series) in
parallel with contactor and solenoid coils etc.
5CONFIGURATION / OPERATION
The user will receive the transmitter perfectly calibrated, without the need for
any adjustments. The configuration performed at the factory has the
following characteristics:
Addr
(Communication Address) = 247
baVd
(Communication speed) = 1200
par
(Parity) = Par
Stop Bit = 1
The DigiConfig for Windows® is a software used for configuration of the
RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD transmitters.
For its installation, run the “DigiConfigSetup.exe” and follow the instructions
as shown.
DigiConfig is provided with a complete help file, giving all the information
necessary for its full use. For using the help feature, start the application and
select the “Help” menu or press the “F1” key.
Access the site www.novusautomation.com in order to obtain the installer for
DigiConfig and the additional manuals.
5.1 SCREENS OF THE TRANSMITTER
Indication screen for the measured values in the transmitter:
1ª Screen: Main
For configuring the communication parameters, press the button (± 5
seconds) until the screen starts blinking, then release the button and press it
again in order to increment. When the desired value appears, release the
button and wait until the screen stops blinking (± 10 seconds). In order to
access the next screens, press the button.
Configuration screen for the Modbus Address – Defines the address of the
module within the Modbus network. Values between 1 and 247.
2ª Screen: Modbus Address
Configuration screen for the Baud-Rate - Defines the Modbus
communication speed. Valid values 1,200, 2,400, 4,800, 9,600, 19,200,
38,400, 57,600 and 115,200.
3ª Screen: Baud-Rate
Configuration screen for the Parity - Defines the parity code used for Modbus
communication. Value 0(none), 1(odd) and 2(even).

RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD Transmitters
NOVUS AUTOMATION 4/6
4ª Screen: Parity
Read-only screens of the values measured by the transmitter:
5ª Screen: Temperature
6ª Screen: Relative Humidity
7ª Screen: Dew Point
6SERIAL COMMUNICATION
The transmitter is provided with RS485 serial communication, operating as a
slave within the Modbus RTU network. The configuration of the transmitter is
performed through the serial (RS485) interface. For configuring the
communication parameters you can use the programming button.
In this section you will find the instructions necessary to perform the data
reading without using the DigiConfig software. In order to assure correct
configuration of the transmitter, always use the DigiConfig software. After
being configured, the input data may be accessed by any other software
capable for Modbus RTU communication.
6.1 MODBUS COMMANDS
The Modbus RTU commands (functions) listed in the table below are
implemented. For further information with respect to each of these
commands and the Modbus protocol in general, please access the site
www.modbus.org.
READ HOLDING REGISTERS – 0x03
This command can be used for reading the value of one or several holding
registers, according to the “Holding Registers Table”.
WRITE HOLDING REGISTERS – 0x06
This command can be used for writing in a holding register, according to the
“Holding Registers Table”.
6.2 DESCRIPTION OF SOME REGISTERS
REGISTER 2 – BAUD-RATE
Defines the Modbus communication speed. The transmitter comes factory-
configured with a Baud-Rate of 1200.
Code
Baud-rate
0 1.200
1 2.400
2
4.800
3 9.600
4 19.200
5
38.400
6 57.600
7 115.200
REGISTER 3 – MODBUS ADDRESS
Defines the address of the transmitter within the Modbus network. Values
between 1 and 247. The transmitter comes factory-configured with address
247.
REGISTER 4 – PARITY
Defines the parity code used for Modbus communication. The transmitter
comes factory-configured with parity even.
Code Parity
0 None
1
Odd
2
Even

RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD Transmitters
NOVUS AUTOMATION 5/6
HOLDING REGISTERS TABLE
The specified addresses correspond to the low-level physical addresses, where zero (0) corresponds to the PLC 40001 address. The minimum and maximum
columns show the range of values valid for each parameter. The R/W column indicates if the parameter is for reading and writing (R/W) or for reading only (R).
Address
Description
Minimum
Maximum
R/W
0 Serial number (word high) 0 65535 R
1
Serial number (word low)
0
65535
R
2 Baud-Rate 0 7 R/W
3
Modbus Address
1
247
R/W
4 Parity 0 2 R/W
5
Firmware release
0
999
R
6
Indication mode
0
3
R/W
7 Temperature value (ºC or ºF).
*
-400 1000 R
8 Relative humidity value (%).
*
0 1000 R
9 Dew point value (ºC or ºF).
*
-400 1000 R
10
Configuration of measurement unit
0
1
R/W
11
Disables configuration via button
0
1
R/W
12 User offset for temperature
*
-100 100 R/W
13 Reserved 0 0 R
14 User offset for humidity
*
-100 100 R/W
15 Reserved
16
Error value
-9999
9999
R/W
17 Title - - R/W
18
Title
-
-
R/W
19 Title - - R/W
20 Title - - R/W
21
Title
-
-
R/W
62 Model 0 11 R
*For the ranges indicated above consider with one decimal place. Example: -100 means -10.0
REGISTER 6 – INDICATION MODE
Defines the indication mode on the display of the sensor values readout. The
transmitter comes factory-configured with indication of temperature and
relative humidity.
Code Description
0 Indicates temperature and relative humidity.
1 Indicates temperature and dew point.
2 Indicates relative humidity and dew point.
3 Indicates temperature only.
REGISTER 7 – TEMPERATURE VALUE (ºC or ºF)
REGISTER 8 – RELATIVE HUMIDITY VALUE (%)
REGISTER 9 – DEW POINT VALUE (ºC or ºF)
Shows the measured value in engineering units. The decimal point is fixed at
one place, the value is exhibited without the decimal point and must be
considered by the reading software.
REGISTER 10 – CONFIGURATION OF MEASUREMENT UNIT
Defines the measurement unit for the temperature and the dew point. The
transmitter comes factory-configured for degrees Celsius (°C).
Code Unit
0 ºC
1 ºF
REGISTER 11 – DISABLES CONFIGURATION VIA BUTTON
Defines the changes of configuration via button.
Code Description
0 Factory-configured default value
1
Disables the configuration change of
communication parameters via button.
REGISTER 12 – USER OFFSET FOR TEMPERATURE
Defines the user offset value in engineering units for the temperature. The
transmitter comes factory-configured with the offset value equal to zero.
REGISTER 14 – USER OFFSET FOR HUMIDITY
Defines the user offset value in engineering units for the relative humidity.
The transmitter comes factory-configured with the offset value equal to zero.
REGISTER 16 – ERROR VALUE
Shows the error value which is transmitted when the sensor has a problem.
The transmitter comes factory-configured with the value -9999.
7SPECIAL CARE
The transmitter is an electronic module and, therefore, will need some
special care when handling it:
•When you open the transmitter to fix it, avoid any contact with the
electronic circuit due to the risk of damage caused by static electricity.
•Take maximum care when connecting the wires.
•When you close the case, the cover must be replaced correctly, thus
assuring the sealing quality of this model.

RHT-WM-485-LCD, RHT-DM-485-LCD and RHT-P10-485-LCD Transmitters
NOVUS AUTOMATION 6/6
7.1 TAKING CARE WITH THE SENSORS
The calibration of the humidity sensor may be changed if it is exposed to
contaminant vapors or extreme humidity and temperature conditions for long
time periods. For accelerating the calibration recovery follow the procedure
as described below:
•Remove the sensor from the capsule.
•If there are solid particles on the sensor, wash it with water.
•Place the sensor within a 80 °C (+/- 10°C) oven for 24 hours.
•Keep the sensor in a place at a temperature between 20 and 30 °C and
humidity over 75 % RH for 48 hours.
•Place the sensor back in the capsule.
IMPORTANT
The sensor used in this transmitter may be damaged or become out of
calibration if it is exposed to chemical agents contaminated atmosphere.
Hydrochloric Acid, Nitric Acid, Sulphuric Acid and Ammonia in high
concentrations may damage the sensor. Acetone, Ethanol and Propylene
Glycol may cause a reversible measurement error.
8WARRANTY
Warranty conditions are available on our website
www.novusautomation.com/warranty.