10
User Manual EE355 Dew Point Sensor
5.1 EE-PCS Product Configuration Software
To use the software for changing the digital communication settings and to perform adjustments, please
proceed as follows:
1. Download the EE-PCS Product Configuration Software from
install it on the PC.
2. Connect the EE355 to the PC using the Modbus configuration cable.
3. Start the EE-PCS software.
4. Follow the instructions on the EE-PCS opening page for scanning the ports and identifying the
connected device.
5. Click on the desired setup or adjustment mode from the main EE-PCS menu on the left and follow
the online instructions of the EE-PCS
5.2 Dew Point Adjustment by the User
Dew point adjustment by the user is possible only at low dew points. The adjustment can only be
carried out if the difference between the ambient temperature and the reference dew point temperature
is <-60 °C.
Example:
Ambient temperature = 20 °C
Reference dew point temperature must be lower than -40 °C.
6 Digital Interface RS485 with Modbus RTU Protocol
The EE355 can be used in Modbus networks based on RS485. Therefore, the RS485 specifications
have to be observed, especially regarding unit loads and bus termination.
For proper function the power supply must be strong enough to ensure supply voltage within the
specified range (see technical data) at any time and at all devices in the bus. This is particularly
relevant when using long and thin cables which can cause high voltage drop.
6.1 Modbus Setup
Factory settings
User selectable values (via EE-PCS)
Baud rate
9 600
9 600, 19 200, 38 400
Data bits
8
8
Parity
Even
None, even, odd
Stop bits
1
1, 2
Slave address
243
1...247
The recommended settings for multiple devices in a Modbus RTU network are 9 600, 8, even, 1.
The EE355 represents 1 unit load on an RS485 network.
Device address, baud rate, parity and stop bits can be set via:
1. EE-PCS Product Configuration Software and the Modbus configuration adapter HA011018.
The EE-PCS can be downloaded free of charge from
2. Modbus protocol in the register 60001 (0x00) and 60002 (0x01).
See Modbus Application Note AN0103 (available on
)
The serial number as ASCII-code is located in the register addresses 0x00...0x07 (16 bits per address).
Please note: When reading the serial number or the sensor name, it is always necessary to read all 8
registers, even if the desired information requires less.
Please note: For obtaining the correct floating point values, both registers have to be read within
the same reading cycle. The measured value can change between two Modbus requests, therefore,
exponent and mantissa may get inconsistent.
