Novatek-electro OB-215 User manual

Technical Specifications
Description
Value
Rated power supply voltage, V
12 - 24
The error of measuring DC voltage in the range of 0-10 V, min
1%
The error of measuring DC in the range of 0-20 mA, min
1%
Temperature measurement range (NTC 10 KB), °C
-25…+125
Temperature measurement error (NTC 10 KB) from -25 to +70 °C
±1
Temperature measurement error (NTC 10 KB) from +70 to +125 °C
±2
Temperature measurement range (PTC 1000), °C
-50…+120
Temperature measurement error (PTC 1000), °C
±1
Temperature measurement range (PT 1000), °C
-50…+250
Temperature measurement error (PT 1000), °C
±1
Max. pulses frequency in “Pulse Counter/Logic Input” mode, Hz
200
Max. voltage given on an «IO1» input, V
12
Max. voltage given on an «IO2» input, V
5
Readiness time, max, s
0.4
Max. switched current with active load, A
8
Quantity and type of relay contact (switching contact)
1
Communication Interface
RS (EIA/TIA)-485
ModBus data exchange protocol
RTU / ASCII
Rated operating condition
continuous
Climatic design version
NC 3.1
Protection rating of the device
IP20
Permissible contamination level
II
Maximal power consumption, W, not more
1
Electric shock protection class
II
Wire cross-section for connection, mm²
0.5 - 1.0
Tightening torque of screws, N*m
0.4
Weight, max., kg
0.07
Overall dimensions, mm
90х18x64
The device meets the requirements of the following: EN 60947-1; EN 60947-6-2; EN 55011; IEC 61000-4-2
Installation is on standard 35 mm DIN-rail
Position in space - arbitrary
Housing material is self-extinguishing plastic
Harmful substances in amounts exceeding maximum permissible concentrations are not available
Table 2 – Settings for OB-215
Description
Range
Factory
setting
Type
W/R
Address
(DEC)
Digital signals measurement:
0 – pulse counter;
1 – logic input/pulse relay.
Analog signals measurement:
2 – voltage measurement;
3 – current measurement.
Temperature measurement:
4 – NTC (10KB) sensor;
5 – PTC1000 sensor;
6 – PT 1000 sensor .
Interface transformation mode:
7 – RS-485 – UART (TTL);
8 – digital sensor (1-Wire, I2C)*.
0…8
1
UINT
W/R
100
Connected digital sensor
0 – DS18B20 (1-Wire);
1 – DHT11 (1-Wire);
2 – DHT21/AM2301 (1-Wire);
3 – DHT22 (1-Wire);
4 – BMP180 (I2C).
0…4
0
UINT
W/R
101
Temperature correction
-99…99
0
INT
W/R
102
Relay control:
0 – control is disabled;
1 – relay contacts are opened at a value above the upper
threshold, they are closed at a value below the lower threshold;
2 – relay contacts are closed at a value above the upper
threshold, they are opened at a value below the lower threshold.
0…2
0
UINT
W/R
103
Upper threshold
-500...2500
250
UINT
W/R
104
Lower threshold
-500...2500
0
0
UINT
W/R
105
Pulse counter mode:
0 – counter on the leading edge of the pulse;
1 – counter on the trailing edge of the pulse;
2 – counter on both edges of the pulse.
0…2
0
UINT
W/R
106
Switch debouncing delay**
1…250
100
UINT
W/R
107
Number of pulses per counting unit ***
1…65534
8000
UINT
W/R
108
RS-485: 0 – ModBus RTU;
1 – ModBus ASCII.
0…1
0
UINT
W/R
109
ModBus UID
1…127
1
UINT
W/R
110
Rate of exchange:
0 – 1200; 1 – 2400; 2 – 4800; 3 – 9600; 4 – 14400; 5 – 19200.
0…5
3
UINT
W/R
111
Parity check and stop bits:
0 – no, 2 stop bits; 1 – even, 1 stop bit; 2 – odd, 1 stop bit.
0…2
0
UINT
W/R
112
Rate of exchange UART(TTL)->RS-485:
0 – 1200; 1 – 2400; 2 – 4800; 3 – 9600; 4 – 14400; 5 – 19200.
0…5
3
UINT
W/R
113
Stop bits for UART(TTL)->RS-485:
0 – 1 stop bit; 1 – 1.5 stop bits; 2 – 2 stop bits.
0…2
0
UINT
W/R
114
Parity check for UART(TTL)->RS-485:
0 – None; 1 – Even; 2 – Odd.
0…2
0
UINT
W/R
115
ModBus password protection ****:
0 – disabled; 1 – enabled.
0…1
0
UINT
W/R
116
ModBus password value
A-Z,a-z,
0-9
admin
STRING
W/R
117-124
Note:
* The sensor to be connected is selected at address 101.
** The delay used in switch debouncing in the Logic Input / Pulse Relay mode; the dimension is in millisecond.
*** Only used if the pulses counter is on. The column "Value" indicates the number of pulses at the input, after
registration of which, the counter is incremented by one. Recording to memory is performed with a periodicity of
1 minute.
**** If ModBus Password Protection is enabled (address 116, value "1"), then to access the recording functions,
you must write the correct password value to addresses 51-59.
Table 1 – Basic Technical Specifications
Table 3 – Output Contact Specifications
Operation
mode
Max. current at
U~250 V [A]
Max. switching power
at U~250 V [VA]
Max. continuous permissible
AC / DC voltage [V]
Max. current at
Ucon =30 V DC [A]
cos φ=1
8
2000
250/30
0.6
Digital I/O module OB-215 hereinafter referred to as the "device" can be used as
the following:
− remote DC voltage meter (0 – 10 V);
− remote DC meter (0 – 20 mA);
− remote temperature meter with the ability to connect sensors NTC (10 KB),
PTC 1000, PT 1000 or digital temperature sensor D18B20;
− temperature regulator for cooling and heating plants;
− pulse counter with saving the result in memory;
− pulse relay with switching current up to 8 A;
− interface converter for RS-485 – UART (TTL).
OB-215 provides:
− equipment control using relay output with switching capacity up to 1.84 kVA;
− tracking the state (closed/open) of the contact at the dry contact input.
RS-485 interface provides control of the connected devices and reading of the
sensors readings via the ModBus protocol.
Parameter setting is set by the user from the Control Panel using the ModBus
RTU/ASCII protocol or any other program that allows working with the ModBus RTU /
ASCII protocol.
The status of the relay output, the presence of the power supply and the data
exchange are displayed using indicators located on the front panel (Fig. 1, it. 1, 2, 3).
The overall dimensions and layout of the device are shown in Fig. 1.
Note:
Temperature sensors are included in the delivery scope as agreed upon.
1 – indicator of data exchange via RS-485 interface (it is on when data is being
exchanged);
2 – indicator of the status of the relay output (it is on with closed relay contacts);
3 – indicator is on when there is supply voltage;
4 – terminals for connecting RS-485 communication;
5 – device power supply terminals;
6 – terminal for reloading (resetting) the device;
7 – terminals for connecting sensors;
8 – output terminals of relay contacts (8 A).
Figure 1
5
6
7
8
1
2
3
+-
+A -B
NO C NC
IO1 IO2
4
R
18
Operation Conditions
The device is intended for operation in the following conditions:
− Ambient temperature: from minus 35 to +45 °С;
− Atmospheric pressure: from 84 to 106.7 kPa;
− Relative humidity (at temperature of +25 °С): 30 … 80 %.
The device is not intended for operation in the following conditions:
− Significant vibration and shocks;
− High humidity;
− Aggressive environment with content in the air of acids, alkalis, etc., as well as
severe contaminations (grease, oil, dust, etc.).
Quality Management System of the device designing and production complies with the requirements of
ISO 9001:2015, IDT
Dear Customer,
Novatek-Electro Ltd. Company thanks you for purchasing our products.
You will be able to use properly the device after carefully studying the Operating Manual.
Keep the Operating Manual throughout the service life of the device.
Designation
Operating Manual
DIGITAL I/O MODULE
OB-215
1

Operation Modes
If the temperature of the device after transportation or storage differs from the
ambient temperature at which it is supposed to be operated, then before connecting to
the mains keep the device under the operating conditions within two hours (because of
condensation may be on the device elements);
ALL CONNECTIONS MUST BE PERFORMED WHEN THE DEVICE IS DE-
ENERGIZED.
It is not allowed to leave exposed portions of wire protruding beyond the terminal
block.
-
Error when performing the installation works may damage the device and
connected devices.
For a reliable contact, tighten the terminal screws with the force indicated in Table
1.
When reducing the tightening torque, the junction point is heated, the terminal
block may be melted and wire can burn. If you increase the tightening torque, it is
possible to have thread failure of the terminal block screws or the compression of
the connected wire.
1. Connect the device as shown in Fig. 2 (when using the device in the analog
signals measurement mode) or in accordance with Fig. 3 (when using the device
with digital sensors).
To connect the device to the ModBus network, use CAT.1 or higher twisted pair
cable.
Note: Contact "A" is for transmission of a non-inverted signal, contact "B" is for an
inverted signal. The power supply for the device must have galvanic isolation from
the network.
2. Switch on the power of the device.
+-
IO1 IO2
-B
+A
N 230 V 50 Hz L
Load up
tо 8 А
I2C SDA
SCK
GND
1-Wire
VCC
Data
GND
UART (TTL)
TXD
RXD
GND
а) b) c)
NO C NC
+A -B
RS-485
DC 12V ...24V
R
OB-215
RP
RPRP
VCC
QF
QF - circuit breaker
(fuse) up to 8 А.
RS-485 +A
OB-215
+-
+A -B
DC 12V ...24V
NO C NC
IO1 IO2
-B
Water flowmeter, electrical
meter
I
O
°t
Temperature sensor
NTC (10KB),
PTC1000, PT1000.
N 230 V 50 Hz L
+
-
0...10 V
0...20 mА Group of switches
Load up
tо 8 А
а) b) c) d) e)
R
QF
QF - circuit breaker
(fuse) up to 8 А.
Figure 2
Figure 3
NOTE: The output relay contact "NO" is "normally open". If necessary, it can be used in
signaling and control systems defined by the User.
The Device Connection
Using the Device
After the power is turned on the indicators « », « » and « » will light up RS-485
for 0.5 s (Fig. 1, it. 1, 2, 3).
To change any parameters you need:
- D o wn lo a d th e OB -2 1 5 Co nt rol P an el p rog ra m at h tt p :/ /no va t ek -
electro.com/en/software.html or any other program that allows you to work with
ModBus RTU/ASCII protocol;
− Connect to the device via RS-485 interface;
− Perform the necessary settings for the OB-215 parameters.
During the data exchange, the "RS-485" indicator flashes, otherwise the "RS-485"
indicator does not light up.
Note: when changing ModBus setting (table 2, addr. 110 – 113) recording the device
setting flash memory a command (table 6, addr. 50, value “0х472С”), after that is
necessary to reload device.
The Device Operation
●●● Measurement Mode ●●●
In this mode, the device measures the readings of sensors connected to the
inputs “IO1" or “IO2" (Fig. 1, it. 7), and depending on the settings, performs the
necessary actions.
●●● ●●● Interface Transformation Mode
In this mode, the device converts the data received via the RS-485 interface
(Modbus RTU/ASCII) to the UART (TTL) interface (Table 2, address 100, value
“7”). More detailed description see in “Transformation of UART (TTL) interfaces
to RS-485”.
●●● ●●● Pulse Counter
Connect the external device as shown in Fig. 2 (e). Set up the device for
operation in the Pulse Counter Mode (Table 2, address 100, value “0”).
In this mode, the device counts the number of pulses at the input “Io2" (of duration
no less than the value indicated in Table 2 (Address 107, value in ms) and stores the
data in memory with a periodicity of 1 minute. If the device has been turned off before
1 minute has ended, the last stored value will be restored upon power-up.
If you change the value in the register (Address 108), all the stored values of the
pulse meter will be deleted.
When the value specified in the register (address 108) is reached, the counter is
incremented by one (Table 6, address 4:5).
●●● ●●● Logic Input/Pulse Relay
When selecting Logic Input / Pulse Relay mode (Table 2, Address 100, Value 1),
or changing the Pulse meter mode (Table 2, Address 106), if the relay contacts
were closed “C – NO” (LED « » lights up), the device will automatically open the
"C - NO" contacts (LED « » turns off).
Logic Input Mode
Connect the device according to Fig. 2 (d). Set up the device for operation in the
Logic Input/Pulse Relay Mode (Table 3, address 100, value “1”), set the required
pulse count mode (Table 2, address 105, value “2”).
If the logic state on the “IO2" terminal (Fig. 1, it. 6) changes to a high level (rising
edge), the device opens the contacts of the "C - NO" relay and closes the contacts
of the "C - NC" relay (Fig. 1, it. 7).
If the logic state on the “IO2" terminal (Fig. 1, it. 6) changes to a low level (falling
edge), the device will open the contacts of the "C - NC" relay and close the "C - NO"
contacts (Fig. 1, it. 7).
Pulse Relay Mode
Connect the device according to Fig. 2 (d). Set up the device for operation in the
Logic Input/Pulse Relay Mode (Table 2, address 100, value “1”), set Pulse Counter
Mode (Table 2, address 106, value “0” or value “1”). For short-time pulse with
duration of at least the value specified in Table 2 (Address 107, the value in ms) at
the «IO2» terminal (Fig. 1, it. 6), the device closes the contacts of the "C - NO" relay
and opens the contacts of the "C - NC" relay.
If the pulse is repeated for a short time, the device will open the contacts of the "C
- NO" relay and close the "C - NC" relay contacts.
●●● ●●● Voltage Measurement
Connect the device according to Fig. 2 (b). Set up the device for operation in the
Voltage measurement mode (Table 2, address 100, value “2”). If it is necessary
that the device monitors the threshold voltage, it is required to write a value other
than "0" in the "Relay control" register (Table 2, address 103). If required, set the
operation thresholds (Table 2, address 104 - upper threshold, address 105 - lower
threshold).
In this mode, the device measures the DC voltage. The measured voltage value
can be read at address 6 (Table 6).
Voltage values are derived to one hundredth of a volt (1234 = 12.34 V; 123 =
1.23 V).
●●● ●●● Current Measurement
Connect the device according to Fig. 2 (a). Set up the device for operation in the
"Current measurement" mode (Table 2, address 100, value “3”). If it is necessary
for the device monitors the threshold current, it is required to write a value other
than "0" in the "Relay control" register (Table 2, address 103). If required, set the
operation thresholds (Table 2, address 104 - upper threshold, address 105 - lower
threshold).
In this mode, the device measures DC. The measured current value can be read
at address 6 (Table 6).
Current values are derived to one hundredth of a milliampere
(1234 = 12,34 mА; 123 = 1,23 mА).
●●● ●●● Temperature Measurement
Connect the device according to Fig. 2 (c). Set up the device for operation in the
Temperature measurement mode (Table 2, address 100, value “4”, “5”, “6”). If it is
necessary for the device monitors the threshold temperature value, it is required to
write a value other than "0" in the register "Relay control" (Table 2, address 103). For
set the operation thresholds to write a value in address 104 - upper threshold and
address 105 - lower threshold(Table 2).
If it is required to correct the temperature, it is necessary to record the correction factor
in the "Temperature Correction" register (Table 2, Address 102).
In this mode, the device measures the temperature with the help of thermistor. The
measured temperature can be read at address 6 (Table 6).
Temperature values are derived to one tenth of a Celsius degree (1234 =
123.4 °С; 123 = 12.3 °С).
Function (hex)
Purpose
Remark
0x03
Reading one or more registers
Maximum 50
0x06
Writing one value to the register
----
Table 4 – List of supported functions
2

Name
Description
W/R
Address
(DEC)
Command register
Command codes:
0x37B6 – switch on the relay;
0x37B7 – switch off the relay;
0x472C – write settings to flash memory;
0x4757 – load settings from flash memory;
0xA4F4 – restart the device;
0xA2C8 – reset to factory settings;
0xF225 – reset the pulse counter (all the values stored in the flash
memory are deleted).
W/R
50
Entering ModBus
Password
(8 characters
ASCII)
To access the recording functions, set the correct password (the
default value is "admin").
To disable the recording functions, set any value other than the
password.
Admissible characters: A-Z; a-z; 0-9.
W/R
51 – 59
Notes:
– W/R – type of access to the write / read register;
– address of the form “50” means the value of 16 bits (UINT);
– address of the form “51 – 59” means a range of 8-bit values.
Name
Description
W/R
Address
(DEC)
Identifier
Device identifier (value 27)
R
0
Firmware
version
bit15 – bit 8
1
15
R
1
bit 7 – bit 0
5
Rejestr stanu
bit 0
0 – pulse counter is disabled;
1 – pulse counter is enabled.
R
2:3
bit 1
0 – counter for leading edge of the pulse is disabled;
1 – counter for leading edge of the pulse is enabled.
bit 2
0 – counter for trailing edge of the pulse is disabled;
1 – counter for trailing edge of the pulse is enabled.
bit 3
0 – counter for both pulse edges is disabled;
1 – counter for both pulse edges is enabled.
bit 4
0 – logical input is disabled;
1 – logical input is enabled.
bit 5
0 – voltage measurement is disabled;
1 – voltage measurement is enabled.
bit 6
0 – current measurement is disabled;
1 – current measurement is enabled.
bit 7
0 – temperature measurement by NTC (10 KB) sensor is disabled;
1 – temperature measurement by NTC (10 KB) sensor is enabled.
bit 8
0 – temperature measurement by the PTC 1000 sensor is disabled;
1 – temperature measurement by the PTC 1000 sensor is enabled.
bit 9
0 – temperature measurement by PT 1000 sensor is disabled;
1 – temperature measurement by PT 1000 sensor is enabled.
bit 10
0 – RS-485 -> UART(TTL) ) is disabled;
1 – RS-485 -> UART(TTL) is enabled.
bit 11
0 – UART (TTL) protocol data is not ready to be sent;
1 – UART (TTL) protocol data is ready to be sent.
bit 12
0 – DS18B20 sensor is disabled;
1 – DS18B20 sensor is enabled.
bit 13
0 – DHT11 sensor is disabled;
1 – DHT11 sensor is enabled.
bit 14
0 – DHT21/AM2301 sensor is disabled;
1 – DHT21/AM2301 sensor is enabled.
bit 15
0 – DHT22 sensor is disabled;
1 – DHT22 sensor is enabled.
bit 16
it is reserved
bit 17
0 – BMP180 sensor is disabled;
1 – BMP180 sensor is enabled.
bit 18
0 - the input «IO2» is open;
1 – the input «IO2» is closed.
bit 19
0 – relay is Off;
1 – relay is On.
bit 20
0 – there is no overvoltage;
1 – there is overvoltage.
bit 21
0 – there is no reduction in voltage;
1 – there is reduction in voltage.
bit 22
0 – there is no overcurrent;
1 – there is overcurrent.
bit 23
0 – there is no decrease of current;
1 – there is decrease of current.
bit 24
0 – there is no temperature rise;
1 – there is temperature rise.
bit 25
0 – there is no temperature reduction;
1 – there is temperature reduction.
bit 29
0 – the device settings are stored;
1 – the device settings are not stored.
bit 30
0 – instrument is calibrated;
1 – instrument is not calibrated.
Pulse counter
-
R
4:5
Measured
value*
-
R
6
Supply voltage
of the device
-
R
7
Digital sensors
Temperature
(х 0.1°С)
-
R
11
Humidity
(х 0.1%)
-
R
12
Pressure (Pа)
-
R
13:14
Notes:
– W/R – type of access to the register as write / read;
– address of the form "1" means the value of 16 bits (UINT);
– address of the form “2:3” means the value of 32 bits (ULONG).
* Measured value from analog sensors (voltage, current, temperature).
Table 5 – Command Register
Table 6 – Additional registers
●●● ●●● Connection of Digital Sensors
The device supports the digital sensors listed in Table 2 (address 101).
The measured value of the digital sensors can be read at the addresses 11 –15,
Table 6 (depending on what value the sensor measures). The query time period of
digital sensors is 3 s.
In case if it is required to correct the temperature measured by the digital sensor,
it is necessary to enter the temperature correction factor in register 102 (Table 2).
If a value other than zero is set in the register 103 (Table 2), the relay will be
controlled based on the measured values in register 11 (Table 6).
Temperature values are derived to one tenth of a Celsius degree (1234 = 123.4 °С;
123 = 12.3 °С).
Note: When connecting sensors via the 1-Wire interface, you need to install an
external resistor to connect the "Data" line to the power supply nominal value from
510 Ohm to 5.1 kOhm.
When connecting sensors via the I2C interface, refer to the specific sensor's
passport.
Converting RS-485 interface to UART (TTL) ●●● ●●●
Connect the device according to Fig. 3 (a). Set up the device for operation in
RS-485-UART (TTL) mode (Table 2, address 100, value “7”).
In this mode, the device receives (transmits) data via the RS-485 ModBus
RTU/ASCII interface (Fig. 1, it. 4) and converts them to the UART interface.
Example of query and response is shown in Fig. 10 and Fig. 11.
Restarting the device and reset to factory settings
If the device needs to be restarted, the "R" and “–“ terminals (Fig. 1) must be
closed and held for 3 seconds.
If you want to restore the factory settings of the device, you must close and
hold the "R" and "–" terminals (Fig. 1) for more than 10 seconds. After 10
seconds, the device automatically restores the factory settings and reloads.
Operation with RS (EIA/TIA) -485 Interface via ModBus Protocol
ОВ-215 allows data exchanging with external devices via the serial interface of
RS (EIA/TIA)-485 via ModBus protocol with the limited set of commands (see
Table 4 for a list of supported functions).
When constructing a network, the principle of the master-slave organization is
used where OB-215 acts as the slave. There can be only one master node and
several slave nodes in the network. As the master node is a personal computer or a
programmable logic controller. With this organization, the initiator of the exchange
cycles can only be the master node.
The queries of the master node are individual (addressed to a particular device).
OB-215 performs transmission, responding to individual queries of the master
node.
If errors are found in receiving queries, or if the received command cannot be
executed, OB-215 as the respond generates an error message.
Addresses (in decimal form) of command registers and their purpose are given in
Table 5.
Addresses (in decimal form) of additional registers and their purpose are given in
Table 6.
●●● ●●● Message formats
The exchange protocol has clearly defined message formats. Compliance with the
formats ensures the correctness and stability of the network.
Byte format
ОВ-215 is configured to operate with one of two formats of data bytes: with parity
control (Fig. 4) and without parity control (Fig. 5). In parity control mode, the type of
control is also indicated: Even or Odd. Transmission of data bits is performed by the
least significant bits forward.
By default (during manufacture) the device is configured to operate without parity
control and with two stop bits.
8 data bits
start bit parity bit stop bit
8 data bits
start bit 2 stop bits
Figure 4 – Byte format with parity control
Figure 5 – Byte format without parity control (2 stop bits)
Byte transfer is performed at speeds of 1200, 2400, 4800, 9600, 14400 and 19200
bps. By default, during manufacturing, the device is configured to operate at a speed of
9600 bps.
Note: for ModBus RTU mode 8 data bits are transmitted, and for MODBUS ASCII
mode 7 data bits are transmitted.
Frame format
The frame length cannot exceed 256 bytes for ModBus RTU and 513 bytes for
ModBus ASCII.
In ModBus RTU mode the start and end of the frame are monitored by silence
intervals of at least 3.5 bytes. The frame must be transmitted as a continuous byte
stream. The correctness of frame acceptance is additionally controlled by checking
the CRC checksum.
The address field occupies one byte. The addresses of the slaves are in the range
from 1 to 247.
Fig. 6 shows the RTU frame format.
silence interval
>3.5 bytes
Address
Function code
Data
CRC checksum
Silence interval
>3.5 bytes
1 byte
1 byte
up to 252
bytes
2 bytes
Figure 6 – RTU frame format
In ModBus ASCII mode the start and end of the frame are controlled by special
characters (symbols (':' 0x3A) – for start of the frame; symbols ('CRLF' 0x0D0x0A) –
for the end of the frame). The frame must be transmitted as a continuous stream of
bytes. The correctness of frame acceptance is additionally controlled by checking the
LRC checksum.
The address field occupies two bytes. The addresses of the slaves are in the range
from 1 to 247.
Fig. 7 shows the ASCII frame format.
3

:
1 byte
Address
Function code
Data
LRC checksum
CRLF
2 bytes
2 bytes
2 bytes
up to 504 bytes
2 bytes
Fig. 7 – ASCII frame format
Note: In MODBUS ASCII mode each byte of data is encoded by two bytes of ASCII code
(for example: 1 byte of data 0x25 is encoded by two bytes of ASCII code 0x32 and 0x35).
●●● ●●● Generation and verification of checksum
The sending device generates a checksum for all bytes of the transmitted
message. ОВ-215 similarly generates a checksum for all bytes of the received
message and compares it with the checksum received from the transmitter. If there is a
mismatch between the generated checksum and the received checksum, an error
message is generated.
CRC checksum generation
The checksum in the message is sent by the least significant byte forward, it is a
cyclic verification code based on the irreducible polynomial 0xA001.
Subroutine for CRC checksum generation in C language:
1: uint16_t GenerateCRC(uint8_t *pSendRecvBuf, uint16_t uCount)
2: {
3: cons uint16_t Polynom = 0xA001;
4: uint16_t crc = 0xFFFF;
5: uint16_t i;
6: uint8_t byte;
7: for(i=0; i<(uCount-2); i++){
8: crc = crc ^ pSendRecvBuf[i];
9: for(byte=0; byte<8; byte++){
10: if((crc& 0x0001) == 0){
11: crc = crc>> 1;
12: }else{
13: crc = crc>> 1;
14: crc = crc ^ Polynom;
15: }
16: }
17: }
18: returncrc;
19: }
LRC checksum generation
The checksum in the message is transmitted by the most significant byte forward,
which is a longitudinal redundancy check.
Subroutine for LRC checksum generation in C language:
1: uint8_t GenerateLRC(uint8_t *pSendRecvBuf, uint16_t uCount)
2: {
3: uint8_t lrc = 0x00;
4: uint16_t i;
5: for(i=0; i<(uCount-1); i++){
6: lrc = (lrc + pSendRecvbuf[i]) & 0xFF;
7: }
8: lrc = ((lrc ^ 0xFF) + 2) & 0xFF;
9: returnlrc;
10: }
●●● ●●● Command system
Function 0x03 – reads a group of registers
Function 0x03 provides reading of the contents of registers OB-215. The master
query contains the address of the initial register, as well as the number of words to
read.
OB-215 response contains the number of bytes to return and the requested data.
The number of registers returned is limited to 50. If the number of registers in the query
exceeds 50 (100 bytes), the response is not divided into frames.
An example of the query and response in ModBus RTU is shown in Fig. 8.
Function 0x06 – recording the register
The function 0x06 provides recording in one OB-215 register. The master query
contains the address of the register and the data to be written.
The device response is the same as the master query and contains the register
address and the set data. An example of the query and response in ModBus RTU
mode is shown in Fig. 9.
Figure 9 – Example of query and response of 0x06 function – register setting
Transformation of UART (TTL) interfaces to RS-485
In the interface transformation mode, if the query was not addressed to OB-215, it
will be redirected to the device connected to «IO1» and «IO2». In this case the
indicator «RS-485» will not change its state.
An example of query and response to the device on UART (TTL) line is shown in Fig. 10.
Address
Function
Init. address HB
Init. address LB
HB data
LB data
CRC LB
CRC HB
01h
06h
00h
A0h
03h
E8h
89h
56h
Query – Register 00A0h = 1000 (INT)
Response
Address
Function
Init. address .HB
Init. address LB
HB data
LB data
CRC LB
CRC HB
01h
06h
00h
A0h
03h
E8h
89h
56h
Figure 8 – Example of query and response of 0x03 function – reading a group of
registers
Address
Function
Init. address HB
Init. address LB
QTY of words HB
QTY of words LB
CRC LB
CRC HB
01h
03h
00h
A0h
00h
02h
C4h
29h
Query
Response – register value 00A0h = 1000 (FLOAT)
Address
Function
QTY of bytes
HW HB data
HW LB data
LW HB data
LW LB data
CRC LB
CRC HB
01h
03h
04h
44h
7Ah
00h
00h
CFh
1Ah
Address
Function
QTY of bytes
HB data
LB data
CRC LB
CRC HB
02h
03h
02h
00h
DFh
BDh
DCh
Address
Function
Init. address HB
Init. address LB
QTY of words HB
QTY of words LB
CRC LB
CRC HB
02h
03h
01h
27h
00h
01h
35h
CEh
Query – register 0127h = 295 (INT)
Response
Figure 10 – An example of query and response of the device on UART(TTL) line
An example of recording to one register of the device on UART (TTL) line is shown in
Fig. 11.
Address
Function
Init. address HB
Init. address LB
QTY of words, HB
QTY of words, LB
CRC LB
CRC HB
02h
06h
01h
27h
00h
7Bh
78h
2Dh
Address
Function
Init. address HB
Init. address LB
QTY of words, HB
QTY of words, LB
CRC LB
CRC HB
02h
06h
01h
27h
00h
7Bh
78h
2Dh
Figure 11 – Example of recording to one register of the device on UART (TTL) line
Query - register 0127h = 295 (INT)
Response
Error code
Name
Comments
0x01
ILLEGAL FUNCTION
Illegal function number
0x02
ILLEGAL DATA ADDRESS
Incorrect address
0x03
ILLEGAL DATA VALUE
Invalid data
0x04
SERVER DEVICE FAILURE
Failure of controller equipment
0x05
ACKNOWLEDGE
Data is not ready
0x06
SERVER DEVICE BUSY
System is busy
0x08
MEMORY PARITY ERROR
Memory error
Maintenance Procedure
Service life and Manufacturer warranty
Transportation and storage
Acceptance certificate
Claims data
●●● ●●● ModBus error codes
Recommended frequency of maintenance is every six months.
Maintenance Procedure:
1) check the connection reliability of the wires, if necessary, clamp with the force
0.4 N*m;
2) visually check the integrity of the housing;
3) if necessary, wipe the front panel and the housing of the device with cloth.
Do not use abrasives and solvents for cleaning.
To carry out installation works and maintenance disconnect the device from the mains.
Do not try to open and repair the device independently.
Do not use the device with mechanical damages of the housing.
It is not allowed water penetration on terminals and internal elements of the device.
During operation and maintenance the regulatory document requirements must be
met, namely:
Regulations for Operation of Consumer Electrical Installations;
Safety Rules for Operation of Consumer Electrical Installations;
Occupational Safety in Operation of Electrical Installations;
The lifetime of the device is 10 years.
Shelf life is 3 years.
Warranty period of the device operation is 5 years from the date of sale.
During the warranty period of operation, the manufacturer performs free repair of the
device, if the user has complied with the requirements of the Operating Manual
Attantion! The User loses the right for warranty service if the device is used with
violation of the requirements of this Operating Manual.
Warranty service is performed at the place of purchase or by the manufacturer of the
device. Post-warranty service of the device is performed by the manufacturer at current
rates.
Before sending for repair, the device should be packed in the original or other packing
excluding mechanical damage.
The device in the original package is permitted to be transported and stored at the
temperature from minus 45 to +60 °C and relative humidity of no more than 80 %, not in
aggressive environment.
OB-215 is checked for operability and accepted in accordance with the requirements
of the current technical documentation, is classified as fit for operation.
Seal
You are kindly requested, in case of the device return and transfer it to the warranty (post-warranty)
service please indicate detailed reason for the return in the field of the claims data.
_________________________________________________________
_________________________________________________________
_________________________________________________________
The Manufacturer is grateful to you for the information about the quality of the device as well as
for comments and suggestions for its operation
For all questions, please contact the manufacturer:
„Novatek-Electro”,
65007, Odessa,
59, Admiral Lazarev Str.; ,
tel. [phone].
tel./fax: [phone]
www.novatek-electro.com
Sale date_________________ 80612 VN1
Head of QCD Date of manufacture
_____________ ___________
Safety precautions
4