PT100 PT1000 8 Road Platinum Resistance RTD High Precision Temperature Acquisition Module MODBUS RS485 | Электроника

PT100 PT1000 8 Road Platinum Resistance RTD High Precision Temperature Acquisition Module MODBUS RS485 | Электроника

Chapter 1 product introduction

A. Summary

MB8RTD 8Platinum resistance high precision acquisition module, platinum resistance(PT100/PT1000 @385 The dual excitation current is respectively500uA/250uA)Equal resistance. The platinum resistance excitation source is a double matching programmable excitation current source, and the acquisition accuracy and speed are higher and faster. The analog signal data collected by isolation is isolated.RS485Interface output; module adoptionModbus-RTUCommunication can fit inPLC,DCSAnd various configuration software and so on.

Signal acquisition, CPU and power input, RS485 communication, electrical signals are isolated from each other, effectively suppressing all kinds of mode and common mode interference, ensuring the accuracy of data, and ensuring the reliable operation of modules.

Two. Characteristic

1. The standard Modbus-RTU protocol is used.

2. The input signal type of the channel can be set according to your own requirements.

3. High precision signal acquisition: high precision 24 bit AD and dual excitation matched programmable current source.

4. The platinum resistor is collected by channel isolation to prevent channel crosstalk effectively.

5. Security: signal acquisition, signal output, power supply, RS485 communication electrical signals are isolated from each other.

6. Communication protection: RS485 communication signal output interface adopts overvoltage over current double protection.

7. The type of input signal and the format of communication can be set by software.

8. Power polarity protection.

Three. Technical indicators

project

parameter

AI

Signal input

1Input channel: 4 channel isolation analog acquisition

2Type of input signal: platinum resistance (PT100/PT1000)

3. Platinum resistance is isolated from each channel and effectively prevents channel crosstalk

4Sampling rate: 8 channels per 400mS collection (2.5 sampling points per second per second)

5Resolution: 24 bit AD collection

6. Acquisition circuit and CPU isolation voltage protection: 1500V

RS485

Communication output

1Communication protocol: MODBUS-RTU

2Interface type: isolation RS485 communication, output interface with overvoltage over current double protection

3Baud rate: 1200BPS, 2400bps, 4800bps, 9600bps, 19200bps

38400bps57600bps, 115200bps.

4Check bit: no check, parity check, odd check

5Setup mode: module address, baud rate, check bit can be set up by software

6. Communication circuit and CPU isolation voltage protection: 1500V

Module size

Individual module size:115mm*90mm*40mm

Installation method

standardDINGuide rail installation or screw fixation

work environment

Temperature: -10 ~ +55 C humidity: 35~85% (non condensation)

Working power supply

1Power supply voltage: 10V~30V wide range power supply, polarity protection with power supply

2Power consumption: less than 3W

Four. measurement accuracy

Input type

measuring range

Display resolution

accuracy

rtd

PT100(-200 - 850 C)

0.1C/0.01 C

0.05%

PT1000(-200 - 850 C)

0.1C/0.01 C

0.05%

Five. Product appearance

Six. Module indicator light and switch function description

1. POW; Module working status indication

A.Green light: module work in running state. B. red light: module configuration parameters have been written, need to re power.

2. COM: Communication status indication

A.Green light flashes: the communication receives the data B. red light: the module is sending data

C.The green light is always bright: the communication RS485 line on A and B connects to the reverse or the wiring has broken line.

3. Right reset switch of module

A. When the communication parameters (module address, baud rate, parity bit) do not know or communication parameter misspecification, and can not establish contact module communication, the solution is to reset the communication parameters; we use the clip to hold the reset switch is not open, 5 seconds after the module of [POW] red light, release the reset switch, the communication parameters has been reset, as long as the power supply module after the restart time, the communication parameters of the module has been reset.

B. Post reset communication parameters: Address: 1, baud rate: 9600bps, check bit: No.

Seven. Typical application wiring diagram

Eight. Terminal definition

terminal

Name

Explain

terminal

Name

Explain

1

+Vs

Power input +

28

A

RS485 ACommunication +

2

GND

Power input -

27

B

RS485 BCommunication -

3

AI0+

Analog input channel 0 positive end

26

C7

Platinum resistance input 7

4

AI0-

The 0 negative end of the analog input channel

25

AI7-

The 7 negative end of the analog input channel

5

C0

Platinum resistance input 0

24

AI7+

Analog input channel 7 positive end

6

AI1+

Analog input channel 1 positive end

23

C6

Platinum resistance input 6

7

AI1-

The 1 negative end of the analog input channel

22

AI6-

The 6 negative end of the analog input channel

8

C0

Platinum resistance input 1

21

AI6+

Analog input channel 6 positive end

9

AI2+

Analog input channel 2 positive end

20

C5

Platinum resistance input 5

10

AI2-

The 2 negative end of the analog input channel

19

AI5-

The 5 negative end of the analog input channel

11

C2

Platinum resistance input 2

18

AI5+

Analog input channel 5 positive end

12

AI3+

Analog input channel 3 positive end

17

C4

Platinum resistance input 4

13

AI3-

The 3 negative end of the analog input channel

16

AI4-

The 4 negative end of the analog input channel

14

C3

Platinum resistance input 3

15

AI4+

Analog input channel 4 positive end

Nine. Schematic block diagram