Seneca Z-8TC-SI User manual

ORIGINAL INSTRUCTIONS
USER MANUAL
Z-8TC-SI
Z-8TC-SI-LAB
8-CHANNEL 24BIT ADC THERMOCOUPLE CONVERTER
SENECA S.r.l.
Via Austria 26 –35127 –Z.I. - PADOVA (PD) - ITALY
Tel. [phone] Fax [phone]
www.seneca.it

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 2
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-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 3
Document revisions
DATE
REVISION
NOTES
AUTHOR
12/10/2022
0
First revision
MM
19/12/2022
1
Summary fix
MM
20/12/2022
2
Modbus Register Fix
MM

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 4
TABLE OF CONTENTS
INTRODUCTION...........................................................................................................6
DESCRIPTION ..........................................................................................................6
TYPE OF SUPPORTED THERMOCOUPLE ................................................................7
MEASUREMENT OF THE COLD JUNCTION..............................................................7
RESPONSE MEASURES AND TIMES ........................................................................8
SAMPLING TIMES AND MEASUREMENT UPDATE TIME.....................................8
FILTER ......................................................................................................................8
MODBUS RESPONSE TIME.....................................................................................8
DEVICE CONFIGURATION..........................................................................................8
USB CONNECTION AND CONFIGURATION RESET.................................................9
FIRMWARE UPDATE...................................................................................................9
MODBUS COMMUNICATION PROTOCOL...............................................................10
SUPPORTED MODBUS FUNCTION CODES.........................................................10
MODBUS REGISTER TABLE....................................................................................11
NUMBERING OF "0-BASED" OR "1-BASED” MODBUS ADDRESSES ..............11
NUMBERING OF MODBUS ADDRESSES WITH "0-BASED" CONVENTION......11
NUMBERING OF MODBUS ADDRESSES WITH "1 BASED" CONVENTION
(STANDARD) ....................................................................................................................12
BIT CONVENTION WITHIN A MODBUS HOLDING REGISTER ...........................13

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 5
MSB AND LSB BYTE CONVENTION WITHIN A MODBUS HOLDING REGISTER
13
REPRESENTATION OF A 32-BIT VALUE IN TWO CONSECUTIVE MODBUS
HOLDING REGISTERS.....................................................................................................14
TYPE OF 32-BIT FLOATING POINT DATA (IEEE 754).........................................14
Z-8TC-SI: MODBUS 4X HOLDING REGISTERS TABLE (FUNCTION CODE 3)...16

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
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-8TC-SI is a thermocouple converter with 8 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 thermocouples and makes them available through the RS485 port using
the Modbus RTU protocol.
The device is able to detect the sensor burnout.
ATTENTION!
Even at constant room temperature, the declared accuracies are achieved after at least 30 minutes
from switching on the device.

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 7
TYPE OF SUPPORTED THERMOCOUPLE
The supported sensors are:
SENSOR
STANDARD
MEASURING
RANGE
J
EN 60584-1:1997
-210 ÷ +1200°C
K
EN 60584-1:1997
-200 ÷ +1372°C
R
EN 60584-1:1997
-50 ÷ +1768°C
S
EN 60584-1:1997
-50 ÷ +1768°C
T
EN 60584-1:1997
-200 ÷ +400°C
B
EN 60584-1:1997
+250 ÷ +1820°C
E
EN 60584-1:1997
-200 ÷ +1000°C
N
EN 60584-1:1997
-200 ÷ +1300°C
L
Gost 8.585-2001
-200 ÷ +800°C
Each channel is independent, therefore it is also possible to use different sensors in the 8 channels.
MEASUREMENT OF THE COLD JUNCTION
The measurement of the cold junction is carried out with 4 sensors positioned near the 4 measurement terminals.
It is possible to activate or not the cold junction correction so that the measurement can also be corrected with
any external equipment.
ATTENTION!
It is necessary to adjust the cold junction compensation for each channel using the offset
parameter.
The internal cold junction compensation uses a sensor whose distance from the terminal varies in
each channel, the use of this function can, therefore, lead to differences between the measured
values of the channels.

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 8
RESPONSE MEASURES AND TIMES
SAMPLING TIMES AND MEASUREMENT UPDATE TIME
Sampling time is configurable from 25ms to 400ms per channel, in particular:
CHANNEL SAMPLING TIME
25 ms
50 ms
100 ms
200 ms
400 ms
To calculate the update time of a channel, consider the following example:
By activating 8 channels and setting a sampling time of 25 ms on all of them, you get an update of the
measurements on channel 1 every: 25*8 = 200 ms.
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)
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.
IF CHARGE FAILURE: Allows you to replace (or not) the measured value with a temperature/mV 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 burnout
SAFETY VALUE It is the value that is displayed in case of fail.
COLD JUNCTION COMPENSATION: Activates or not the internal compensation of the cold junction.
FILTERING: Allows you to activate the filter on the selected channel, filtering allows you to obtain a slower but
stable measurement.
CHANNEL SPEED: Allows you to set the channel sampling time
TERMINAL CONFIGURATION: Allows you to choose the configuration of the measurement terminals according
to the Z-8TC-SI or Z-8TC-SI-LAB model.
INTERPRETATION OF FLOATING POINTS: 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.

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 9
CHANNEL OFFSET Allows you to set the measurement offset value.
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 factory configuration, use the configuration software.
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) Turn dip switch 9 to ON.
3) Now the device is in "firmware update" mode (the TX led stays on), connect the USB cable to the PC
4) Power up the device
5) The device will be displayed in the PC as an "RP1-RP2” external unit
6) Copy the new firmware (uf2 extension) to the root of the "RP1-RP2” unit
Once the firmware file has been copied, the device will automatically reboot
7) Remove power from the device
8) Turn dip switch 9 to OFF, the device is now in “normal operation” mode.
9) Power up the device
10) It is possible to check that the fw update was successful by connecting the device to the Easy Setup
software, the firmware revision is shown in the bottom left:

User Manual
Z-8TC-SI
ALL RIGHTS RESERVED. NO PART OF THIS
PUBLICATION MAY BE REPRODUCED WITHOUT
PRIOR PERMISSION.
www.seneca.it
MI00595-2-EN
Page 10
MODBUS COMMUNICATION PROTOCOL
The supported communication protocol is:
▪Modbus RTU Slave (from both the RS485 and USB ports)
For more information on these protocols, see the website:
http://www.modbus.org/specs.php.
SUPPORTED MODBUS FUNCTION CODES
The following Modbus functions are supported:
▪Read Holding Register (function 3)
▪Write Single Register (function 6)
▪Write Multiple registers (function 16)
ATTENTION!
All 32-bit values are contained in 2 consecutive registers
ATTENTION!
All 64-bit values are contained in 4 consecutive registers
ATTENTION!
Any registers with RW* (in flash memory) can be written up to about 10000 times
The programmer must make sure the PLC/Master Modbus does not exceed this limit