Seneca Z-4RTD2-SI User manual

ORIGINAL INSTRUCTIONS
USER MANUAL
Z-4RTD2-SI
CONVERTER FOR THERMISTORS WITH 4 CHANNELS AND 24BIT ADC
SENECA S.r.l.
Via Austria 26 –35127 –Z.I. - PADOVA (PD) - ITALY
Tel. [phone] Fax [phone]
www.seneca.it

User Manual
Z-4RTD2-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
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The content of this documentation refers to products and technologies described in it.
All technical data contained in the document may be changed without notice.
The content of this documentation is subject to periodic review.
To use the product safely and effectively, read the following instructions carefully before use.
The product must be used only for the use for which it was designed and manufactured: any other use is under
the full responsibility of the user.
Installation, programming and set-up are allowed only to authorized, physically and intellectually suitable
operators.
Set-up must be performed only after correct installation and the user must follow all the operations described in
the installation manual carefully.
Seneca is not responsible for failures, breakages and accidents caused by ignorance or failure to apply the
stated requirements.
Seneca is not responsible for any unauthorized modifications.
Seneca reserves the right to modify the device, for any commercial or construction requirement, without the
obligation to promptly update the reference manuals.
No liability for the contents of this document can be accepted.
Use the concepts, examples and other content at your own risk.
There may be errors and inaccuracies in this document that could damage your system, so proceed with caution,
the author(s) will not take responsibility for it.
Technical specifications are subject to change without notice.
CONTACT US
Technical support
[email protected]
Product information
[email protected]
This document is the property of SENECA srl.
Copies and reproduction are prohibited unless authorised

User Manual
Z-4RTD2-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00584-1-EN
Page 3
Document revisions
DATE
REVISION
NOTES
AUTHOR
22/06/2022
0
First revision
MM
10/10/2022
1
Added sampling rate
changes for fw 1010
revision.
Added info on float
swapped registers
Corrected errors in the
Modbus register list
MM

User Manual
Z-4RTD2-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
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MI00584-1-EN
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TABLE OF CONTENTS
INTRODUCTION...........................................................................................................6
DESCRIPTION ..........................................................................................................6
COMMUNICATION PORT SPECIFICATIONS..........................................................6
TYPE OF SUPPORTED SENSORS.............................................................................7
RESPONSE MEASURES AND TIMES ........................................................................7
SAMPLING TIMES AND MEASUREMENT UPDATE TIME.....................................7
FILTER ......................................................................................................................8
MODBUS RESPONSE TIME.....................................................................................8
DEVICE CONFIGURATION..........................................................................................9
USB CONNECTION AND CONFIGURATION RESET.................................................9
FIRMWARE UPDATE.................................................................................................10
MODBUS COMMUNICATION PROTOCOL...............................................................11
SUPPORTED MODBUS FUNCTION CODES.........................................................11
MODBUS REGISTER TABLE....................................................................................12
NUMBERING OF "0-BASED" OR "1-BASED” MODBUS ADDRESSES ..............13
NUMBERING OF MODBUS ADDRESSES WITH "0-BASED" CONVENTION......13
NUMBERING OF MODBUS ADDRESSES WITH "1 BASED" CONVENTION
(STANDARD) ....................................................................................................................13
BIT CONVENTION WITHIN A MODBUS HOLDING REGISTER ...........................14

User Manual
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MSB AND LSB BYTE CONVENTION WITHIN A MODBUS HOLDING REGISTER
15
REPRESENTATION OF A 32-BIT VALUE IN TWO CONSECUTIVE MODBUS
HOLDING REGISTERS.....................................................................................................15
TYPE OF 32-BIT FLOATING POINT DATA (IEEE 754).........................................16
Z-4RTD2-SI: MODBUS 4X HOLDING REGISTER TABLE (FUNCTION CODE 3) 17

User Manual
Z-4RTD2-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
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Page 6
INTRODUCTION
ATTENTION!
This user manual extends the information from the installation manual to the configuration of the
device. Use the installation manual for more information.
ATTENTION!
In any case, SENECA s.r.l. or its suppliers will not be responsible for the loss of data/revenue or
consequential or incidental damages due to negligence or bad/improper management of the device,
even if SENECA is well aware of these possible damages.
SENECA, its subsidiaries, affiliates, group companies, suppliers and distributors do not guarantee that
the functions fully meet the customer's expectations or that the device, firmware and software should
have no errors or operate continuously.
DESCRIPTION
Z-4RTD2-SI is a converter for thermistors with four independent and isolated measurement channels equipped
with an analogue-digital converter with a 24-bit resolution.
The insulation relates to both the power supply and the RS485 communication port.
The device measures the value of the thermistors and makes them available through the RS485 port using the
Modbus RTU protocol.
COMMUNICATION PORT SPECIFICATIONS
RS485 COMMUNICATION PORTS
Number
1
Baudrate
From 2400 to 115200 bit/s configurable
Parity, Data bit, Stop bit
Configurable
Protocol
Modbus RTU Slave
USB COMMUNICATION PORT
Number
1
Protocol
Modbus RTU Slave
Use
For configuration with Easy-setup software and firmware update

User Manual
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TYPE OF SUPPORTED SENSORS
The supported sensors are:
SENSOR
STANDARD
MEASURING
RANGE
PT100
EN 60751/A2 (ITS-90)
-200 ÷ +650°C
PT500
EN 60751/A2 (ITS-90)
-200 ÷ +750°C
PT1000
EN 60751/A2 (ITS-90)
-200 ÷ +210°C
NI100
DIN 43760
-60 ÷ +250°C
CU50
GOST 6651-2009
-180 ÷ +200°C
CU100
GOST 6651-2009
-180 ÷ +200°C
Ni120
DIN 43760
-60 ÷ +250°C
NI1000
DIN 43760
-60 ÷ +250°C
Each channel is independent, therefore it is also possible to use different sensors in the 4 channels.
RESPONSE MEASURES AND TIMES
SAMPLING TIMES AND MEASUREMENT UPDATE TIME
The sampling time is configurable from 25ms to 400ms per channel.
SAMPLING TIME PER
CHANNEL
25 ms
50 ms
100 ms
200 ms
400 ms
for example:
By activating 4 channels and setting a sampling time of 100ms on all, you get a measurement update every:
100*4 = 400 ms.
By activating 2 channels at 25 ms and 2 channels at 100 ms you get a measurement update every: 25*2 + 100*2
= 250 ms.

User Manual
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ATTENTION!
In order not to lose the settings, NEVER update the firmware with a version older than the one installed
on the device.
FILTER
To each channel it is possible to insert a low pass filter to stabilize the measurement, it is a 10-sample moving
average filter.
MODBUS RESPONSE TIME
Modbus Response Time: 5 ms (typical)

User Manual
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DEVICE CONFIGURATION
The device can be configured using the Easy Setup or Easy Setup 2 software, configurations are as follows:
SENSOR TYPE: allows you to select the type of sensor connected to the channel, it is also possible to
disconnect the channel if it is not used.
UNIT OF MEASUREMENT: allows you to set whether the measurement must be in °C or in Ohm
3-WIRE MEASUREMENT: Allows you to set whether the sensor measurement will be carried out with 3 or 4
wires (for the 2-wire connection, refer to the 4-wire connection)
CHANNEL SPEED: Allows you to set the channel sampling time
IF CHARGE FAILURE: Allows you to replace (or not) the measured value with a temperature/resistance safety
value set by the user in the event of a fault. The failure can be caused by:
1) Sensor beyond measurement values
2) Sensor breakage
ACTIVATE FILTER: Allows you to activate the filter on the selected channel, filtering allows you to obtain a
slower but stable measurement.
INTERPRETATION OF FLOATING POINTS: It allows you to set whether the single precision (32 bit) Floating
Point registers are to be interpreted with the most significant value on the high word or on the low word.
USB CONNECTION AND CONFIGURATION RESET
The front USB port allows a simple connection to configure the device via the configuration software.
If it is necessary to restore the instrument's initial configuration, use the configuration software.

User Manual
Z-4RTD2-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
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FIRMWARE UPDATE
Through the USB port it is possible to update the firmware.
To update the firmware:
1) Disconnect the device from the power supply;
2) Holding down the firmware update button (positioned as shown in the figure), reconnect the device to
the power supply
3) Now the instrument is in update mode, stop pressing the update key and connect the USB cable to the
PC
4) The device will be displayed in the PC as an "RP1-RP2” external unit
5) Copy the new firmware (uf2 extension) to the root of the "RP1-RP2” unit