Novus RHT-WM-485-LCD User manual

RHT-WM-485-LCD,
RHT-DM-485-LCD and
RHT-P10-485-LCD
TEMPERATURE AND HUMIDITY TRANSMITTER
USER GUIDE V2.0x A

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1. SAFETY ALERTS...............................................................................................................................................................................................3
2. INTRODUCTION ................................................................................................................................................................................................4
2.1 IDENTIFICATION ........................................................................................................................................................................................4
3. MECHANICAL INSTALLATION .........................................................................................................................................................................5
3.1 RHT-DM-485-LCD .......................................................................................................................................................................................5
3.2 RHT-WM-485-LCD ......................................................................................................................................................................................5
3.3 RHT-P10-485-LCD ......................................................................................................................................................................................6
4. ELECTRICAL INSTALLATION...........................................................................................................................................................................7
4.1 INSTALLATION RECOMMENDATIONS.....................................................................................................................................................7
5. CONFIGURATION / OPERATION .....................................................................................................................................................................8
5.1 SCREENS OF THE TRANSMITTER ..........................................................................................................................................................8
6. SERIAL COMMUNICATION...............................................................................................................................................................................9
6.1 MODBUS COMMANDS ..............................................................................................................................................................................9
6.2 DESCRIPTION OF SOME REGISTERS.....................................................................................................................................................9
6.3 HOLDING REGISTERS TABLE................................................................................................................................................................10
7. SPECIAL CARE................................................................................................................................................................................................12
7.1 CARE WITH SENSORS............................................................................................................................................................................12
8. SPECIFICATIONS............................................................................................................................................................................................13
8.1 MEASUREMENT ACCURACY AND OPERATIONAL LIMITS OF THE SENSORS ................................................................................13
9. WARRANTY .....................................................................................................................................................................................................14

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1. SAFETY ALERTS
The symbols below are used in the device and throughout this manual to draw the user’s attention to essential information related to device safety
and use.
CAUTION
Read the manual fully before installing and
operating the device.
CAUTION OR HAZARD
Risk of electric shock.
ATTENTION
Material sensitive to static charge. Check
precautions before handling.
All safety recommendations appearing in this manual must be followed to ensure personal safety and prevent damage to the instrument or system.
If the instrument is used in a manner other than that specified in this manual, the device’s safety protections may not be effective.

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2. INTRODUCTION
RHT-WM-485-LCD, RHT-DM-485-LCD, and RHT-P10-485-LCD transmitters include high accuracy 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. DigiConfig allows the configuration of all transmitters 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.
2.1 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:
Figure 1 –Transmitter main screen
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.
Figure 2 –Transmitter second screen
Communication Address: Value programmed for identifying the transmitter of the Modbus network. Programmable between 1and 247.

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3. MECHANICAL INSTALLATION
3.1 RHT-DM-485-LCD
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. The figure below shows flange dimensions and holes. Available in stainless
steel or polyamide 6.6.
Figure 3 –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.
Figure 4 –Dimensions of the RHT-DM-485-LCD model
3.2 RHT-WM-485-LCD
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 the figure below.
The transmitter must be fixed with the sensor capsule directed downwards to assure the specific accuracy and protection level.
Figure 5 –Fixing bores and dimensions of the RHT-WM-485-LCD model

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Figure 6 –Dimensions of the RHT-WM-485-LCD model
3.3 RHT-P10-485-LCD
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.
Figure 7 –Remote sensor dimensions
Figure 8 –Mounting flange
The flange is not bundled with the transmitter. It must be ordered
separately.

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4. ELECTRICAL INSTALLATION
The figure below 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 DD+ ABidirectional data line. Blue wire
4 D0 D- BBidirectional inverted data line. Brown wire
Table 1 –Electrical connections
Figure 9 –Electrical connections
Figure 10 –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.
4.1 INSTALLATION RECOMMENDATIONS
•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.

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5. CONFIGURATION / OPERATION
The user will receive the transmitter perfectly calibrated, without the need for any adjustments. The configuration performed at the factory has the
following features:
Addr (Communication Address) = 247
baVd (Communication speed) = 115200
par (Parity) = Par
Stop Bit = 1
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 comes with an unabridged help tutorial, containing all the necessary information for you to use it. If you want to use help tutorial, start the
application, and select the Help menu or press F1.
Access the site www.novusautomation.com 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:
Screen No. 1: Main screen
For configuring the communication parameters, press the button (± 5 seconds) until the screen starts blinking, then release the button and press
it again to increment. When the desired value appears, release the button, and wait until the screen stops blinking (± 10 seconds). 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
Screen No. 2: 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.
Screen No. 3: Baud Rate
Configuration screen for the Parity: Defines the parity code used for Modbus communication. Value 0(none), 1(odd) and 2(even).
Screen No. 4: Parity
Read-only screens of the values measured by the transmitter:
Screen No. 5: Temperature
Screen No. 6: Relative humidity
Screen No. 7: Dew point

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6. SERIAL 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. 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 115200.
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
Table 2 –Baud Rate
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
Table 3 –Parity
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.
Table 4 –Indication mode

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REGISTER 7 – TEMPERATURE VALUE (°C OR °F)
REGISTER 8 – RELATIVE HUMIDITY VALUE (%)
REGISTER 9 – DEW POINT VALUE (°C OR °F)
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 UNITY
0 °C
1 °F
Table 5 –Unity
REGISTER 11 – DISABLED 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.
Table 6 –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 0
(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 0
(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.
6.3 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 (°C or °F)* -400 1000 R
8 Relative humidity value (%)* 0 1000 R
9 Dew point value (°C or °F)* -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

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ADDRESS DESCRIPTION MINIMUM MAXIMUM 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
Table 7 –Registers
* For the ranges indicated above consider with one decimal place. Example: -100 means -10.0.

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7. SPECIAL CARE
The transmitter is an electronic module and, therefore, will need some particular 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.
7.1 CARE WITH 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 deionized water.
•Place the sensor within 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, Sulfuric Acid, and Ammonia in high concentrations may damage the sensor. Acetone, Ethanol and Propylene Glycol
may cause a reversible measurement error.

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8. SPECIFICATIONS
FEATURES
RHT-WM-485-LCD, RHT-DM-485-LCD, and RHT-P10-485-LCD
Transmitter operating
temperature
•WM Model: From -40 °C to 70 °C.
•DM Model: From -40 °C to 100 °C.
Sensor and Rod (RHT-DM): See Figure 11.
Sensor measuring range
Temperature: -40 °C to 100°C.
Relative Humidity (RH): 0 to 100 % RH (No Condensing).
Dew Point: -40 °C and 100 °C.
Electromagnetic compatibility
EM 61326:2000
Measurement accuracy
Measurement resolution
See Figure 11.
Note: a small measurement error can be eliminated adjusting the OFFSET parameter of the software.
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
Power supply
3 seconds
12 Vdc to 30 Vdc, consumption < 16 mA
Housing Polycarbonate
Protection index
Product suitable 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).
Table 8 –Specifications
8.1 MEASUREMENT ACCURACY AND OPERATIONAL LIMITS OF THE SENSORS
Figure 11 –Accuracy of humidity and temperature measurement

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9. WARRANTY
Warranty conditions are available on our website www.novusautomation.com/warranty.