renatta RN-WN-N01 Series Temperature and Humidity Transmitter Instruction Manual

: June 13, 2024
: renatta

renatta RN-WN-N01 Series Temperature and Humidity Transmitter

renatta-RN-WN-N01-Series-Temperature-and-Humidity-Transmitter-
product

Product Information

The Temperature and Humidity Transmitter (Type 485) is a compact device with a built-in temperature and humidity sensor. It utilizes imported industrial- grade microprocessor chips and high-precision temperature sensors to ensure reliability and precision. The transmitter adopts the 485 communication interface with the ModBus-RTU communication protocol, allowing for customizable communication address and baud rate. It has a communication distance of up to 2000 meters and features anti-reverse connection protection.

The transmitter has a built-in temperature and humidity sensor with a compact size. The circuit uses imported
industrial-grade microprocessor chips and imported high-precision temperature sensors to ensure excellent reliability and high precision of the product. The product adopts 485 communication interface standard ModBus-RTU communication protocol, the communication address and baud rate can be set, and the communication distance is up to 2000 meters. The product has anti-reverse connection protection function, the connection will not burn the device.

Features

485 communication interface, standard ModBus-RTU protocol, communication address and baud rate can be set, the communication line can be up to 2000 meters;
Temperature accuracy ± 0.5 ℃, humidity accuracy ± 4% RH, high precision, low drift;
Adopt special EMC anti-interference device, can withstand strong electromagnetic interference on site, industrial grade processing chip, wide range of use;
5 ~ 28V wide voltage range power supply, long-distance centralized power supply can still work normally;
Anti-connection and reverse protection function of power supply, reverse connection of positive and negative poles will not burn the device.

485 communication interface with Modbus-RTU protocol
Customizable communication address and baud rate
Communication line distance of up to 2000 meters
Special EMC anti-interference device for strong electromagnetic interference resistance
Wide voltage range power supply (5-28V)
Anti-connection and reverse protection function

Main Specifications

DC power supply (default): 5-28V
Maximum power consumption: 0.05W
Accuracy: humidity ±1%, temperature ±0.1°C
Operating temperature: -40°C to +80°C
Output signal: Modbus-RTU communication protocol 485 signal
Temperature display resolution: 0.1°C
Humidity display resolution: 0.1%RH
Temperature and humidity refresh time: 2 seconds
Long-term stability: temperature ±1%RH/year, humidity ±15%/year
Response time: 4 seconds for 1 m/s wind speed
Parameter settings: Software-based

Product Number
RN WNN01- renatta-RN-WN-N01-Series-Temperature-and-Humidity-Transmitter-
fig-2

Equipment Installation Instructions

Check before installation

Equipment List:

1 transmitter device
Conformity certificate, warranty card, calibration report, etc.
USB to 485 (optional)
485 terminal resistance (gift from multiple devices)
One buckle

Interface Description

Power supply and 485 signal
The transmitter supports a wide voltage power input of 5-28V. When connecting the 485 signal line, please note the two lines A The wide voltage power input can be 5 ~ 28V. When connecting the 485 signal line, please note that the two lines A \ B cannot be reversed, and the addresses of multiple devices on the bus must not conﬂict。

wiring

485Field wiring instructions
When multiple 485 model devices are connected to the same bus, there are certain requirements for ﬁeld wiring. For details, please consult the after- sales engineer.

letter of agreement

Communication basic parameters

Data frame format deﬁnition
Using Modbus-RTU communication protocol, the format is as follows:

Time of initial structure ≥ 4 bytes
Address code = 1 byte
Function code = 1 byte
Data area = N bytes
Error check = 16-bit CRC code
End structure time ≥ 4 bytes
Address code: It is the address of the transmitter, which is unique in the communication network (factory default 0x01).
Function code: instruction function instruction issued by the host, this transmitter only uses function code 0x03 (r ead register data).
Data area: The data area is speciﬁc communication data, pay attention to the high byte of 16bits data ﬁrst!
CRC code: two-byte check code.
Host inquiry frame structure：
Slave response frame structure:

Register address

Communication protocol example and explanation

Read the temperature and humidity value of device address 0x01

Inquiry frame (hexadecimal):

Response frame (hexadecimal): (for example, read temperature is -20.5 ℃, humidity is 25.8% RH) renatta-RN-WN-N01-Series-Temperature-and-Humidity-
Transmitter-fig-9 renatta-RN-
WN-N01-Series-Temperature-and-Humidity-Transmitter-
fig-10

Temperature calculation:
When the temperature is lower than 0 ℃, the temperature data is uploaded in the form of complement. Temperature: FF37 H (Hexadecimal) = -205 => Temperature = -20.5 ℃

Humidity calculation:
Humidity: 102H (Hexadecimal) = 258 => Humidity = 25.8% RH

Read the temperature calibration value of device address 0x01

Inquiry frame (hexadecimal):

Response frame (hexadecimal): (for example, the temperature calibration value read is -1.0 ℃) renatta-RN-WN-N01-Series-Temperature-and-Humidity-
Transmitter-fig-12

Calculation of temperature calibration value:
When the temperature calibration value is less than 0, the temperature calibration value data is uploaded in the form of complement.

Temperature calibration value: FF F6 H (hexadecimal) = -10 => temperature calibration value = -1.0 ℃

Set the temperature calibration value of device address 0x01

The temperature calibration value is issued at -1.0 degrees. When the temperature calibration value is less than 0, the temperature calibration value data is delivered in the form of a complement.

Temperature calibration value: FF F6 H (hexadecimal) = -10 => temperature calibration value = -1.0 ℃

Request frame (hexadecimal):

Humidity calibration value operation is similar to temperature calibration value operation.

Change the device with address 01 to 02

Request frame (hexadecimal):

Set the baud rate of device address 0x01 to 4800
Change the baud rate of device 01 to 4800 (00 stands for 2400, 01 stands for 4800, 02 stands for 9600, and 03 stands for unknown baud rate)

Request frame (hexadecimal):

Reply Frame (Hexadecimal)

Read device address

Inquiry frame (hexadecimal):

Response frame (hexadecimal): (for example, the address read is 1) renatta-
RN-WN-N01-Series-Temperature-and-Humidity-Transmitter-
fig-31

Reading device baud rate

Inquiry frame (hexadecimal):

Response frame (hexadecimal): For example, the baud rate read is 4800 (00 stands for 2400, 01 stands for 4800, 02 stands for 9600, and 03 stands for unknown baud rate) renatta-RN-WN-N01-Series-Temperature-and-Humidity-
Transmitter-fig-33

Conﬁgure software use

Software selection

Open the data package, select “Debug Software” — “485 Parameter Conﬁguration Software”

parameter settings

select the correct COM port (“COM” port in “My Computer-Properties-Device Manager-Port”), the following ﬁgure lists the driver names of several diﬀerent 485 converters.
Only connect one device and power it on, click the test baud rate of the software, the software will test the baud rate and address of the current device, the default baud rate is 4800bit / s, the default address is 0x01.
Modify the address and baud rate according to the needs of use, and at the same time can query the current functional status of the device.
If the test is unsuccessful, please recheck the device wiring and 485 driver installation.

Common problems and solutions

The device cannot be connected to a PLC or computer possible reason:

The selected COM port is incorrect.
The device address is wrong, or there are devices with duplicate addresses (the factory default is all 1).
Baud rate, check mode, data bit, stop bit error.
The host’s polling interval and waiting time for answering are too short, and both need to be set above 200ms.
The 485 bus is disconnected, or the A and B lines are reversed.
If the number of devices is too large or the wiring is too long, power should be supplied nearby, and a 485 booster should be added, and 120Ω terminal resistance should be added at the same time.
The USB to 485 driver is not installed or damaged.
The equipment is damaged.

Temperature and humidity transmitter instruction manual (type 485) V1.0

Renatta Control Technology
www.renatta.com