Abstract:
This article describes the Mitsubishi FX series PLC and the sine inverter RS-485 communication between the control and data formats, a detailed analysis of the communication control system and general analog speed control speed control system is superior compared sex. Application examples are given and the PLC program design ideas.
Introduction:
in the modern industrial control systems, PLC and inverter integrated application of the most common. More traditional application of the general is the use of PLC s output contacts to control the inverter drive intermediate relay start, stop or multi-speed, PLC plus D / A converter frequency extension control. By D / A converter frequency control expansion module, the analog signals are vulnerable to the fluctuation and inconsistency result from the analog signal attenuation caused by inconsistent, making the overall system stability and reliability of reduced work. From an economic point of view, when the need to control multiple inverter, if the use of D / A expansion module, the cost would be to use RS-485 communication times, for example: a FX2N-2DA (two analog output module) price of more than 1000 yuan, and an FX2N-485BD (FX series 485 board) price of 200 yuan. Using RS-485 communication control, it is easy to achieve multi-frequency converter and the percentage of linkage between the synchronization run. The system is low cost, high precision signals (up to a maximum resolution of frequency converter), transmission distance, and strong anti-jamming features.
system configuration:
roller mechanical control system were used in three inverters, respectively, control the travel carriage, spindle, extruder speed. Be divided into automatic / manual control, touch screen interface to boot interface manual, automatic and manual / automatic selection of four interface; automatic state selection by the touch screen to control the ratio of 3 different inverters of the frequency and start and stop; MANUAL three inverter can operate independently of Reversible and frequency.
system hardware components and connections:
under the control of the system requirements, use the following components:
1. Japan s Mitsubishi PLC selected FX1N-14MR;
2. PLC485 communications expansion board FX1N-485-BD (with frequency converter for communication);
3. To WEINVIEWMT5005.7 inch touch screen color touch screen 256;
4. Touch screen with the PLC connection cable;
5. Inverter developed by our own sine SINE303 series drives, has a low torque large, load capacity, protection function, etc.;
touch screen control interface diagram:
hardware connection diagram:
communication protocol:
sine inverter built-in standard RS-485 communication interface, the communication protocol format the following table: protocol format to explain:
packet header: 02H (header starting byte)
from the machine address: converter from the machine, the inverter shall be the machine address of PLC communication address from the machine by the inverter s parameter settings (the host for the industrial computer or PLC can be compiled process controllers, etc.).
status code: status code from the machine converter. The parameter setting state, running state, stop state, fault state and the factory test state.
status code: the host sending the command code, the corresponding operation from the machine, such as jog, start, stop, read data, write data, clear the fault and so on. .
Data Address: the address of the code converter functions (communication) number.
dataInformation: data definitions, scope 0-32000. No decimal point, such as: If function code content was 10.00, sending the data of 1000, the case of 50.0 per 500. Send by: start high byte, low byte of recurrence, the data byte of the high 4 and low 4-bit split and converted into ASCII code, the first high to low sent.
exclusive or checksum: Data meanings: data frame to data from the machine address of the differences or results. Only 2 bytes or 3 bytes different results and then XOR with the first 4 bytes, and so on to 13 bytes. Treatment Results: When the calibration results is less than equal to 1FH, then check the results plus 20H.
data packets End: 03H (the end of the packet bytes)
(from the machine address, state code, state code, different, or check the send method: the command code of the high 4 and low 4-bit split and converted into ASCII code, the first high to low sent)
with Mitsubishi PLC s communication procedures FX1N series of examples as follows:
inverter parameter settings:
1. Control the car s converter:
F0.05 = 1F0.04 = 1 (terminal control, RUN terminal ON / OFF control is being transferred / stop, F / R terminal inversion of control / stop).
F0.06 = 2 (485 computer input valid), F5.28 = 1 (the machine communication station number is set to 1 #)
2. Control spindle inverter:
F0.05 = 1F0.04 = 1 (terminal control, RUN terminal ON / OFF control is being transferred / stop, F / R terminal inversion of control / stop).
F0.06 = 2 (485 computer input valid), F5.28 = 2 (local communication station number set to 2 #)
3. Control the car s converter:
F0.05 = 1F0.04 = 1 (terminal control, RUN terminal ON / OFF control is being transferred / stop, F / R terminal inversion of control / stop).
F0.06 = 2 (485 computer input valid), F5.28 = 3 (local communication station number set to 3 #)
Conclusion:
using PLC communication with the inverter, with the wiring simple, high control precision, low cost, especially suitable for the inverter and synchronous, the proportion of linkage and the inverter frequency higher precision occasions.
References:
1. Micro PLC Mitsubishi FX Series Programming Manual.
2. Micro PLC Mitsubishi FX Communications User Manual.
3. Sine SINE303 series inverter manual.
4. Sine SINE303 Series Frequency computer communication protocols.