Modbus – Relaisbord schakelen

Hardware

Wellicht ken je deze boards wel voor de microcontroller, daar worden ze geschakeld via een hoog/laag signaal, dit board is geschikt om via modbus RS485 aan te sturen.

Technische Specificaties (ENG)

  • DC 12V power supply (voltage range 9-13V )
  • Standby current (all relays closed) 12MA, 1 relay open 40MA, 2 relays open 67MA, 3 relays open 95MA,4 relays open 121MA,5 relays open 147MA,6 relays open 173MA, 7 relays open 198MA,8 relays open 223MA
  • “open” “close”  “Momentary” “Self-locking” “Interlock” “Delay” 6 Commands
  • MODBUS RTU command
  • Under the “Delay” command ,the maximum delay is 255 seconds
  • MODBUS commands can be made serial HyperTerminal (serial assistant)  OR “Modbus Poll” Enter;
  • Under the MODBUS command mode, it can support up to 64 devices in parallel
  • Maximum load: 10A / 250VAC, 10A / 125VAC, 10A / 30VDC, 10A / 28VDC, 10A / 12VDC

Standaard modbus instellingen

  • 9600 Band
  • 8 Data bits
  • None Parity
  • 1 Stop Bit

Instellen van het mobus adres:

Het instellen van een adres van dit relaisbord (4 kanaals) gebeurt met DIP switch A0-4 (5 bit), hiermee zijn 32 adressen mogelijk:

Let op: Met de laatste dipswitch (in dit voorbeeld A5) stel je de modbus functie in:

  • A5 uit = AT commando
  • A5 aan = Modbus RTU

Mobus registers

MODBUS 06 Command (Control command ,HEX):

Bytes Number 1 2 3 4 5 6 7 8
MODBUS Definitions Slave ID Function  Address  Data CRC Check
Function Device Address Function Channel number Command Delay time CRC Check
Open 0x00-0x2F 0x06 0x0001-

0x0008

0x01 0x00 2Bytes CRC
Close 0x00-0x2F 0x06 0x0001-

0x0008

0x02 0x00 2Bytes CRC
Toggle (Self-locking) 0x00-0x2F 0x06 0x0001-

0x0008

0x03 0x00 2Bytes CRC
Latch (Inter-locking) 0x00-0x2F 0x06 0x0001-

0x0008

0x04 0x00 2Bytes CRC
Momentary (Non-locking) 0x00-0x2F 0x06 0x0001-

0x0008

0x05 0x00 2Bytes CRC
Delay 0x00-0x2F 0x06 0x0001-

0x0008

0x06 0x00-0xff 2Bytes CRC

Remarks:

  • Momentary mode, delay time is 1 seconds
  • Delay mode, delay time is 0-255 seconds

Return command:

  • Command is active, return to send commands; instruction is invalid no return.

MODBUS 03 Command (Read status command ,HEX):

Bytes Number 1 2 3 4 5 6 7 8
MODBUS Definitions Slave ID Function  Address  Data CRC Check
Function Device Address Function Starting register address Register length CRC Check
Read Channel 1 State 0x00-0x2F 0x03 0x0001

 

0x0001

 

Read Channel 2 State 0x00-0x2F 0x03 0x0002 0x0001

 

Read 2 consecutive channels status 0x00-0x2F 0x03 0x0001-0x0003 0x0002

 

Read 3 consecutive channels status 0x00-0x2F 0x03 0x0001-0x0002 0x0003

 

Read all 8 channels status 0x00-0x2F 0x03 0x0001 0x0008

 

Read status command returns (function code 03, HEX format):

Bytes length 1 1 1 2
MODBUS Definitions Slave ID Function data length  data CRC16 Check
Function Device Address Function data length Relay state

0x0001 open

0x0000 close

CRC16 Check
Channel 1

open

0x00-0x1F 0x03 0x02

 

0x0001
Channel 1

close

0x00-0x1F 0x03 0x02

 

0x0000
Channel 2

open

0x00-0x1F 0x03 0x02

 

0x0001
Channel 2

close

0x00-0x1F 0x03 0x02

 

0x0000
Channel 1 open

Channel 2 open

0x00-0x1F 0x03 0x04

 

0x0001 0x0001
Channel 1 open

Channel 2 close

0x00-0x1F 0x03 0x04

 

0x0001 0x0000
Channel 1 close

Channel 2 open

0x00-0x1F 0x03 0x04

 

0x0000 0x0001
Channel 1 close

Channel 2 close

0x00-0x1F 0x03 0x04

 

0x0000 0x0000

Voorbeeld schakelen (uit de handleiding)

Examples (Slave ID is 1,DIP switch state)
Channel 1 Open: 01 06 00 01 01 00 D9 9A
Channel 1 Close: 01 06 00 01 02 00 D9 6A
Channel 1 Toggle: 01 06 00 01 03 00 D8 FA
Channel 1 Latch: 01 06 00 01 04 00 DA CA
Channel 1 Momentary: 01 06 00 01 05 00 DB 5A
Channel 1 Delay 10 seconds : 01 06 00 01 06 0A 5B AD
Channel 1 Delay 100 seconds: 01 06 00 01 06 64 DA 41

Channel 2 Open: 01 06 00 02 01 00 29 9A
Channel 2 Close: 01 06 00 02 02 00 29 6A
Channel 2 Toggle: 01 06 00 02 03 00 28 FA
Channel 2 Latch: 01 06 00 02 04 00 2A CA
Channel 2 Momentary: 01 06 00 02 05 00 2B 5A
Channel 2 Delay 10 seconds: 01 06 00 02 06 0A AB AD
Channel 2 Delay 100 seconds: 01 06 00 02 06 64 2A 41

Read state (assuming that the channel 1 is open, the channel 2 is close).
Read channel 1 state: 01 03 00 01 00 01 D5 CA
Return open: 01 03 02 00 01 79 84
Read channel 2 state: 01 03 00 02 00 01 25 CA
Return close: 01 03 02 00 00 B8 44
Read channel 1 and channel 2 state: 01 03 00 01 00 02 95 CB
Return channel open and channel 2 close: 01 03 04 00 01 00 00 AB F3


Voorbeeld schakelen