novus RHT-Air Wireless Device for Temperature Relative Humidity and Dew Point Instruction Manual

RHT-Air
WIRELESS DEVICE FOR TEMPERATURE,
RELATIVE HUMIDITY AND DEW POINT
INSTRUCTIONS MANUAL
V2.0x A

INTRODUCTION

RHT-Air comes with a high accuracy and stability sensor to measure temperature, relative humidity, and dew point. Because it operates with a microprocessor, it can be fully configured through its USB and IEEE 802.15.4 interfaces. DigiConfig software enables all the device resources to be configured.
RHT-Air can be configured to display the temperature, the relative humidity, and the dew point and can display up to two of them simultaneously. RHT-Air must be connected to an AirGate-Modbus so that it can access its parameters when in operation. AirGate-Modbus will provide Modbus RTU access to its registers over the IEEE 802.15.4 wireless network. In addition to battery operation with a typical range of 1 year (for an update interval higher than 60 seconds and stable connection in an IEEE 802.15.4 network), RHT-Air can also be powered by an external source.

IDENTIFICATION

The following elements appear in the front part of the device:

Communication Indicator (COM): It signals that the device is receiving data from the Modbus network.
Button (Programming): This button is used to configure the Modbus address, the Update Interval and to screen changes. Temperature: Environment temperature measured by the device.
Relative Humidity: Relative humidity measured by the device.

Communication Address: Programmed value to identify the Modbus network device. Programmable between1 and 246.

SPECIFICATIONS

Relative Humidity (RH): 0.0 to 100.0 % RH
(No condensation)
Dew Point -40 °C and 100 °C (-40 °F to 212 °F)
Measurements Accuracy| See Figure 3.
Note: It is possible to perform an Offset
adjustment using the DigiConfig software to reduce the measurement error found.
Response time (Sensor)| Temperature: Up to 30 s with air movement at 1 m/s.
Measurements Accuracy| Humidity: Up to 8 s with air movement at 1 m/s (20 to 80% RH).
Interval between updates| Configurable between 15 seconds and 10 minutes (600 s).
Power supply| Power supply: 12 Vcc to 30 Vcc. Consumption < 100 mA.
Internal battery (included): Lithium 3.6 Vcc 1/2 AA 0,80 Ah. Omnicell manufacturer (ER14250HD model) or EEMB manufacturer (ER14250M model).
Estimated battery life| Typical: 1 year – Update interval greater than 60 seconds.
Connections| •Internal USB Device (micro-B) for configuration and firmware update.
•RP-SMA female connector for antenna (included).
•M12 connector for external power (cable included).

Communication| Modbus RTU about Wireless IEEE 802.15.4 protocol (AirGate- Modbus necessary).
---|---
Wireless| •Maximum transmission power of 25,11 mW (14 dBm).
•Maximum Range: 500 meters line-of-sight in the open field.
•Data rate: RF 250 Kbps.
•Receptor sensibility – 92 dBm.
•Operation band: ISM 2.4 GHz.
•DSSS Technology (Direct Sequence Spread Spectrum).
•OQPSK Modulation (Offset Quadrature Phase Shift Keying).
•15 operation channels.
•AES-CBC-128 (Advanced Encryption Standard).
Housing| Polycarbonate.
Protection Index| IP40
Dimensions| 60 x 70 x 35 mm.
Antenna measurement: 105 mm. Sensor measurement: 37,2 mm.
Weight| 171 grams / 40 grams (cable).
Configuration software| DigiConfig — Configuration software for Windows.
Certifications| CE, FCC, ANATEL (00172-13-07089). Contains FCC ID: 2AXVWBAIRR- NOVUSAIR.
Electromagnetic compatibility| EMC: EN61326-1:2006 CISPR111EN55011,
EN61000-4-2, EN61000-4-3, EN61000-4-4,
EN61000-4-6, EN61000-4-8

ACCURACY OF MEASUREMENTS AND OPERATIONAL LIMITS OF SENSORS

Figure 3 ­ Accuracy of the humidity and temperature measurement

MECHANICAL INSTALLATION

RHT-Air was designed to be attached to walls. By removing the device cover, users will have access to two molding holes of the base, as shown in Figure 4.
The device should be attached with the sensor capsule facing downwards to ensure accuracy and the specified level of protection.

CONFIGURATION

CONFIGURATION VIA USB INTERFACE

Initially, the first configuration must be done through a USB interface.

• Remove the four set screws of the front panel of the RHT-Air device, taking the necessary precaution not to apply force on the internal connector of the electronic circuit.
• To configure the USB interface, connect the cable as shown in the following figure. The external power cable is not used during the configuration because the device will be powered by the USB interface.

ELECTRICAL INSTALLATION

EXTERNAL POWER SUPPLY CONNECTION

Figure 8 below shows RHT-Air’s necessary electrical connection. Terminals 1 and 2 are to be used in the electrical connection and terminals 3 and 4 are not used.

**** Disconnect the power supply while the device is opened.

M8 4-pin female power supply cable. For replacement, consult the commercial department.

INSTALLATION RECOMMENDATIONS

• Conductors of small electric signals must be separated from activation conductors or higher current or power in the system plan. If possible, in grounded conduits.
• The instrument supply must come from a network proper for instrumentation.
• In control and monitoring applications, it is essential to consider what may happen when any part of the system fails.
• It is recommended to use RC FILTERS (47 and 100 nF, series) in parallel with coils of contactors and solenoids, etc.

BATTERY POWER SUPPLY

RHT-Air can be supplied by an internal battery whenever the device is not energized by the electrical grid. It can be a power backup, is automatically used when the power from the external power source is not present.

RHT-Air is shipped with a battery insulation film. Therefore, it must be removed before first use. When the device is not in use, remove the battery or put the insulation film on it to avoid the battery’s premature death.
The following step-by-step will guide you on how to proceed to power the device using the battery.

• Remove the four screws from the RHT-Air front panel. Be careful not to force the internal connector of the electronic circuit.
• After removing the front panel, remove the insulation film from the battery.

REPLACING THE INTERNAL BATTERY
It is possible to check the battery charge through register “29”. A fully charged battery typically has power above 3.6 V. As you use the RHT-Air, the power of the battery will gradually decrease.
It is recommended to periodically check the value of the “29” register. When it reaches values below 3.3 V, a battery change must be scheduled (this register may present a measurement error of up to 5 %).
Note: Even when the power is below 100 %, the device will operate normally.

**** The only suitable replacement battery for this device is: Omnicell manufacturer (ER14250HD model) or EEMB manufacturer (ER14250M model).

• Remove the four molding screws of the front panel, taking the necessary precaution not to apply force on the internal connector of the electronic circuit. After removing the front panel, replace the battery, taking the necessary precaution not to touch the electronic circuit.
• Insert a new battery and replace the front panel carefully, placing the four molding screws.

BATTERY LIFE
The battery is estimated to last for over a year for update intervals higher than 60 seconds. There is a fine line between its life and how the device is used.
The lower the sensor reading interval, the shorter it will last, as it may. In the worst-case scenario, last for 30 days only.
To save battery energy, you must put as much time as possible between upgrades. The transmission power level for communicating with the AirGateModbus network also influences the battery life. Thus, the device must be configured to operate at minimum power and as close as possible to an AirGate-Modbus network as possible.
In addition, to achieve autonomy over one year, it is necessary to use it in a network where there is an AirGate-Modbus, stable and available for pairing.
Every need to repair with the network significantly degrades the battery.
In a situation where RHT-Air is well installed, it is possible that the battery lasts more than 2 years.

**** Remove the battery or insert the insulation film when the device is not in use. Leaving the powered device out of range of a Wireless network will cause the device to continually attempt to pair, which may lead to premature battery death.

CONFIGURATION / OPERATION

DigiConfig is a Windows software used for configuring RHT-Air. To install it, please run the file “DigiConfigSetup.exe”, available on our website www.novusautomation.com.
DigiConfig comes with an unabridged help tutorial, containing all the necessary information for you to use it. If you want to use the help tutorial, start the application, select the Help menu, or press F1.
Check our website forget the DigiConfig installer and the additional manual guides.
Users will receive the fully calibrated adjustment-free device. The original configuration is shown below:
Addr (Communication address) = 246
Time (Update interval) = 60 s
To configure it for the first time, it is necessary to remove the front cover and connect it to a computer through a mini-B USB cable. The initial configurations for wireless are described as follows:
PAN ID (Network Identifier) = 22350 (0x574E)
RF Power (Power Level) = 0 dBm

RHT-Air SCREENS

Indication screen of the values measured in the device:

To configure the communication parameters, you should press the button (for about 5 seconds) until it starts to blink. Release it and press it again to expand it. When the expected value appears, release the button, and wait until the screen stops blinking (for about 10 seconds). If you want to move on to the following screens, press the button.
Modbus Address configuration screen: Sets the address of the module on the Modbus network. Values between 1 and 246.

Unit configuration screen: Sets which temperature unit should be used (°C or °F).

Display screens only for measured values on the device:

WIRELESS COMMUNICATION

RHT-Air has an IEEE 802.15.4 wireless communication to connect to AirGates- Modbus that has its firmware updated to a version more recent than V1.23. The first RHT-Air configuration must be performed via the USB interface through the DigiConfig software. In it, the necessary parameters for communication with the AirGates network should be set. After the first time, it is configured and matched with an AirGate-Modbus, RHT-Air will operate as a Modbus RTU slave. From this moment on, all its resources can be accessed by reading its registers anywhere in any Modbus RTU network.
Some settings can be made via the programming button.

In this section, you will find the necessary information to carry out the data readings without the use of the DigiConfig software. To ensure the correct device configuration, use the DigiConfig software. Once configured, the data of its inputs can be accessed by any other software with Modbus RTU communication capability.

MODBUS COMMANDS

The following Modbus RTU commands (functions) are implemented. For further information on each one of these functions and on the Modbus protocol in general, go to www.modbus.org.
READ HOLDING REGISTERS ­ 0x03
This function can be used to read a value of one or up to 42 retentive registers, as per the Retentive Registers Table.

WRITE HOLDING REGISTERS ­ 0x06
This function can be used to write in a retentive register, as per the Retentive Registers Table.

DESCRIPTION OF SOME REGISTERS

Once RHT-Air meets an AirGate-Modbus and is matched, this AirGate will be last published by RHT-Air. Therefore, when the Master of the Modbus network requires that the RH-Air address be read, the response is sent immediately and the expiration of this publication can be checked through register 30, which shows how long it has been since the last publication.

REGISTER 6 ­ PAN ID
A common identifier for each IEEE 802.15.4 wireless network. All devices on the same network (AirGates-Modbus and RHTs-Air) must be configured with the same PAN ID.

REGISTER 7 ­ ENCRYPTION

This register should be used to enable or disable the use of encryption. If it is enabled, the encryption key should be the same used for all devices configured with the same PAN ID.

REGISTER 16 ­ POWER LEVEL

According to the variations presented in the table below, the power level can be adjusted as needed. The higher the power set, the greater the range and the greater the consumption. It is suggested that the lowest value possible be configured, if RHT-Air is not able to communicate with the AirGate-Modbus, it will automatically increase the transmission power gradually, until it is able to communicate with AirGate-Modbus or reach the highest configurable limit. It may be that this register is configured with a value, and, after some time, this value may be altered to adjust to a communicable power.

REGISTER 27 ­ OPERATION CHANNEL

It indicates the operation channel in which the device is operating in the network. It may vary from 11 to 25, in that every channel is equivalent to one frequency of operation. The network will always operate on the channel with less interference among all the 15 possible ones.

REGISTER 28 ­ LINK QUALITY INDICATOR
It serves to inform the quality of the reception link of the connection between the device and the AirGate-Modbus with which it is matched. This value is obtained by measuring the power of the last package received. This power is measured in dBm, which is a logarithmic power unit in mW. The LQI may vary from -100 dBm (worst reception quality) to -15 dBm (best reception quality).

For devices operating in ideal environments where there are no obstacles and no electromagnetic interference, the LQI will behave in a way close to the graph below, where the comparison between different power levels is performed for the distance versus LQI ratio.

The table below lists the values obtained in the LQI reading with the evaluation of signal quality. This information can be viewed more intuitively in the DigiConfig Diagnostics tab.

NOTE: The model described in the graphic takes into consideration the propagation channel only. LQI may vary due to several factors, such as due to peripheral obstacles like trees, buildings, and hills that interfere in the propagation channels as explained by the Fresnel Zone phenomenon.

REGISTER 29 ­ BATTERY POWER
It has the value of measuring the voltage level of the battery in the engineering unit. The decimal point is fixed in three houses. The value is without the point and must be predicted by the reading software. Reading the battery voltage may show an error of up to 5 %.
Typically, a battery with 100 % of its load has a voltage above 3.6V. Depending on the use of RHT-Air, the battery will gradually decrease voltage. It is recommended to periodically check the value of this register so that, when it reaches values below 3.3 V, a battery change is scheduled.
Checking the battery capacity can be done using the Diagnostics tab of the DigiConfig software, which will display an icon. The evaluation of battery capacity can be performed according to the criteria presented in the table below:

battery.
Lower than 3200| Bad – Replace the battery as soon as
possible.

NOTE 1: Even when the power is below 100 %, the device will operate normally.
NOTE 2: The gradual failure of the battery power is not linear, therefore, though the device is able to continue working under tensions below 3.0 V, when it reaches this level, there is little left for its life, since the power will fail more quickly.
NOTE 3: While the device is being powered from an external source, you may notice a slight rise in battery voltage. This is because the battery voltage increases whenever power from the same battery is not being consumed.
NOTE 4: The machine operating temperature has a significant impact on the battery capacity. Temperatures below 0 °C will typically shorten the battery life.
NOTE 5: Battery chemistry is directly affected by the ambient temperature. High temperatures tend to raise battery voltage, as low temperatures tend to decrease battery voltage. In both cases, autonomy is negatively affected.
NOTE 6: The update time, as well as the operating power, have a significant impact on the battery capacity. If the device is configured for the lowest update interval, the battery will typically last less. The same happens when the device is far from the AirGate-Modbus with which it should be matched, needing a higher transmission power to operate.
NOTE 7: Remove the battery or insert the insulation film when the device is not in use. Leaving the powered device out of range of a Wireless network will cause the device to continually attempt to pair, which may lead to premature battery death.

REGISTER 30 ­ LAST POLL DURATION
Every time RHT-Air publishes something on AirGate-Modbus, this register gets a zero value. Every 100 ms, this register is increased in 1 unit to indicate how long it has been since the last publication.

REGISTER 31 ­ MODBUS ADDRESS
It sets the address of the device on the Modbus network. This address identifies the device on the Modbus network. Its configuration may range from 1 and 247. There cannot be more than one piece of device with the same address on the same network. RHT-Air is originally manufactured with the address 246. When connected to a USB interface, it always responds to Modbus functions through the address 246. When it is in operation, it always responds through the address it was configured for in this register according to the communication parameters of the Modbus network on which it was installed.

REGISTER 32 ­ UPDATE TIME
It sets the configuration for how often the device wakes to publish information on the AirGate-Modbus with which it is matched and updates the IHM screen.
The shorter the update time, the more recent the data available to the master of the Modbus network will be, but the higher the energy consumption spent, and the battery life will be proportionately shorter. On the other hand, the higher the update time set, the lower the energy consumption spent will be, thus providing a longer life for the battery.

REGISTER 33 ­ INDICATION MODE
It sets the mode of indication of the values to read on the display. The device is originally manufactured with the indication of temperature and relative humidity.

REGISTER 34 – CONFIGURATION OF THE MEASUREMENT UNIT
It sets the measurement unit for both temperature and dew point. The device is originally configured in (°C).

REGISTER 35 – DISABLES CONFIGURATION THROUGH A BUTTON
It sets the alteration of configuration through a button.

REGISTER 36 – USER OFFSET FOR TEMPERATURE
It sets the users’ offset value in engineering units for temperature. The device offset value is originally zero.

REGISTER 37 – USER OFFSET FOR HUMIDITY
It sets the users’ offset value in engineering units for relative humidity. The device offset value is originally zero.
REGISTER 38 – ERROR VALUE
It contains the error value that is transmitted when the sensor has a problem. The device’s original value is -9999.

REGISTER 39 – TEMPERATURE VALUE (°C or °F)
It contains the value of temperature measurement in an engineering unit, including the users’ offset corrections for temperature. The decimal point is fixed in one place. The value has no point and must be provided in the reading software.
REGISTER 40 – RELATIVE HUMIDITY VALUE (%)
It contains the value of relative humidity measurement in an engineering unit, including the users’ offset corrections for temperature. The decimal point is fixed in one space. The value has no point and must be provided in the reading software.
REGISTER 41 – DEW POINT VALUE (°C or °F)
It has the value of the measurement in an engineering unit. The decimal point is fixed in one place. The value has no point and must be provided in the reading software.

HOLDING REGISTERS TABLE
The specified addresses correspond to lower-level physical addresses, as zero (0) corresponds to the PLC 40001 address. The columns reserved for Minimum and Maximum contain a range of valid values for each parameter. The column reserved for R/W indicates whether the parameters are meant for reading and writing (R/W) or reading only (R).

• For the abovementioned table ranges, one decimal place should be considered. Example: -100 means -10.0.
  ** For the abovementioned table ranges, three decimal places should be considered. Example: 3600 means 3600 V.

SPECIAL CARE

• Because it is an electronic module, the device needs some care in handling:
• When opening it for fixation, you should keep away from the electronic circuit due to the risk of damages caused by static electricity.
• The wiring should be carefully observed.
• When closing the box, the cover must be replaced properly, thus ensuring that it is sealed.

CARE WITH SENSORS

The calibration of the humidity sensor can be altered if it is exposed to contaminating vapors or extreme humidity or temperature conditions for longer periods. To speed up the calibration, do as follows:

• Remove the sensor from the capsule.
• If solid particles are deposed on the sensor, wash it with water.
• Place the sensor in an oven at 80 °C (+ -10 °C) for 24 hours.
• Place the sensor for 48 hours in a place at around 20 and 30 °C and humidity higher than 75 % RH.
• Replace the sensor into the capsule.

BATTERY CARE

**** Remove the battery or insert the insulation film when the device is not in use. Leaving the powered device out of range of a Wireless network will cause the device to continually attempt to pair, which may lead to premature battery death.

The Lithium battery, due to its chemical behavior, may present some passivation symptoms when not used for long periods of time. This can be observed by checking the battery voltage after 2 hours of device operation.
If the battery voltage measures less than 3.5 V, then the battery may be passivated (not necessarily worn out). If this is the case, please try applying the following procedures to recover the battery:

• Operate the device at its maximum power (14 dBm) and minimum sample period (15 s).
• Let the instrument operate continuously in the above conditions for 24 h while monitoring the battery voltage through reading register number 29 or the Diagnostic menu of the DigiConfig software.
• If the battery voltage exceeds 3.5 V, the battery can be considered rehabilitated (depassivated). The device is then ready to use.
• In case the above does not work, please remove the battery from the device and discharge it for 5 minutes connecting a 220 Ohm resistor across the terminals.
• After that, you should put the battery in the device and leave it running for about 2 hours. If the battery has a voltage above 3.5 V, it has been undone and can operate normally.
• If after going through the above procedures the battery still fails to work properly, please contact technical assistance for arranging battery replacement.

IMPORTANT

The sensor used in this device may be damaged or de-calibrated if exposed to contaminated atmospheres with chemical agents. Hydrochloric acid, nitric acid, sulfuric acid, and ammonia in high concentrations may damage the sensor. Acetone, ethanol, and propylene glycol may cause reversible measurement errors.

TROUBLESHOOTING

PROBLEMS COMMUNICATING WITH THE DEVICE VIA USB INTERFACE OR DURING

FIRMWARE UPDATE

If you have problems communicating the device via the USB interface or there are problems during firmware update, it is recommended to perform the following procedure to speed communication and minimize incompatibility issues:
a. Open the Device Manager:
b. Open the COM port setting of the device:
c. Open advanced COM port configuration options:
d. Uncheck the Use FIFO buffers option:

CERTIFICATIONS

FCC
Contains FCC ID: 2AXVWBAIRR-NOVUSAIR
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment.
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense

WARNING: To satisfy FCC RF exposure requirements, a separation distance of 20 cm or more should be maintained between the antenna of this device and persons during operation. To ensure compliance, operations at closer distances than this are not recommended. This device and its antenna(s) must not be co- located or operating in conjunction with any other
This product has been tested with a Wellshow AR0035EW0119N antenna.
Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

Canada
This Class A device complies with Canadian standard ICES-003.

CE Mark
This is a Class A product. In a domestic environment, this product may cause radio interference in which case the user may be required to take adequate measures.

ANATEL
This device is homologated by ANATEL, in accordance with the procedures regulated by Resolution 242/2000, and meets the technical requirements applied.
This equipment is not subject to protection from harmful interference and may not cause interference with duly authorized systems.
For more information, see the ANATEL website www.anatel.gov.br.

WARRANTY

Warranty conditions are available on our website www.novusautomation.com/warranty.
NOVUS AUTOMATION

References

• Anatel — Agência Nacional de Telecomunicações
• NOVUS Automation Inc. - Controllers, Thermostats, Data Loggers, Solid State Relays, Sensors, Transmitters, SCADA, Data Acquisition and Temperature Controllers

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