1 Basic differences

2 Software difference between 5S vs 5V

High speed counter configuration

5V as below

5S is as below

More detail information,please check the product catalog

3 Functions that 3V has but 5V does not

BD board

LX5V does not support LX3V-2RS485-BD

LX5V does not support LX3V-ETH-BD

Analog BD board expansion address

Provides the function of analog board BD to modify parameters such as filtering. For specific functions, please refer to the below link:
1. LX3 series: 5-9 System-special address - Wecon (we-con.com.cn)
2. LX5 series: 15 Appendix - Wecon (we-con.com.cn) 15 Appendix - Wecon (we-con.com.cn)

PLDID

Program label function, when the label of the program corresponds to the label of the PLC, the ladder diagram can be uploaded and downloaded. Clearing the memory does not clear this tag either. It is mainly to limit the ladder diagram used by PLC.

Instructions

(1) NOP instruction (null instruction)

(2) TRAN instruction (SFC transfer begins)

(3) FEND instruction (main program ends)

(4) IRET instruction (interrupt return)

(5) SRET instruction (subroutine return)

(6) SPD instruction

(7) DRVI2 instruction

(8) PTO/DPTO instruction(envelope pulse command)

(9) DABS instruction

(10) RSLIST instruction

(11) CPAVL instruction（communication BD configuration）

Unsupported special register function (M8000, D8000)

Clock related

Clock function not supported by LX5V

High-speed counter ring counting function

X0~X5 pulse capture function

4 3V and 5V incompatible functions

(These can be automatically converted in the future)

General register

Incompatible part

1. T250~T255 of LX3V are 100ms timers, while T250~T255 of LX5V are 10ms timer.

2. C200~C234 of LX3V are double word counters, LX5V is changed to single word, and LC0~LC255 are added as double word counters.

3. LX3V's high-speed counters C235~C255 are no longer used. In LX5V, the high-speed counter type is configured through the configuration table, and HSC0~HSC7 is selected as the high-speed input counter according to the channel. See the high-speed input function for details.

4. CJ instruction uses pointer P63 to jump directly to END instruction in 3V,  but P63 of LX5V is a normal label.

5. Pointer I is cancelled in LX5V, please check the programming mode for details.

Programming method

Subroutine

(For details, please refer to LX5V Programming Manual Chapter 1.4-Subroutine Branch)

Use of LX3V subroutines

Use of LX5V subroutines

Add new subroutine: project management -> subroutine -> right click -> new

Subroutine can be directly used in the main program by calling its name.

Interrupt

(For details, please refer to LX5V Programming Manual Chapter 1.4-Branch)

LX3V interrupt

The interrupt program is under FEND and returns with IRET. The meaning of the specific interrupt is distinguished by the pointer I number.(Refer to EI/DI instruction in 3V)

The 1ms interrupt program of LX3V is as follows:

LX5V interrupt

Add new interrupt: Project Management -> program->Interrupt -> New

Interrupt configuration: select interrupt mode

Instructions

OUT instruction

Double word counter

LX3V: OUT C200 KXXX

LX5V: OUT LC0 KXXX

The C200~C219 of LX3V are converted to LC0~LC19 of LX5V (Un-power-down save).

The OUT C220~C234 of LX3V is converted to OUT LC100~LC114 of LX5V (Power-down save).

CALL instruction

LX3V: OUT C200 PXXX

LX5V: OUT LC0 subroutine name(See LX5V programming manual for details)

CJ instruction

LX5V does not support CJ P63 to jump directly to the END instruction.

LX5V does not support CJ instructions to jump into subroutines and interrupts.

DI, EI instructions

There is no need to connect the contact before the DI instruction of LX3V.

The contact must be connected before the DI instruction of LX5V. 

DHSCS instruction

LX3V: calls interrupt using IXX

LX5V: calls interrupts by using the interrupt program name

CPAVL instruction

CPVAL is used to configure communication BD boards in 3V. LX5V does not currently support it.

CPVAL is used to switch electronic cam table in LX3V. LX5V uses ECAMCUT instruction(Refer to Chapter 9.1 of LX5V Programming Manual for details).

TRH instruction

LX3V: input parameters are floating

LX5V: input parameters are integer

ASC instruction

 LX3V: input strings don't need double quotes

 LX5V: input strings need double quotes

5 High-speed input function

Use on LX3V

Find the high-speed input counter you need to use according to the following table:

Through special registers, configure the functions such as frequency multiplication and counting direction.

Use the OUT instruction to start the high-speed counter counting.

Use on LX5V

According to channel, select the HSC register to use:

Configure the high-speed counter mode through the host computer configuration table：

Use the OUT instruction to start the high-speed counter counting.

Difference between high-speed counters on LX5V and LX3V

LX3V updates the count value when the OUT instruction is executed, which is affected by the scan cycle.

LX5V is updated in the 100us interrupt, not affected by the scan cycle, and provides the REF instruction to refresh the current high-speed counter value immediately.

LX5V single-phase high-speed counter supports filtering function, configurable 0~17us.

LX5V high-speed input counter will update the input frequency in the special soft element (SD) every 100us.

6 High-speed output function

High-speed pulse commands are the same in the use of commands.

High-speed pulse command difference.

PLSR2 instruction parameter address is different

Special device change

1. LX3V has multiple high-speed pulse devices that are shared by multiple axes, while LX5V is separated. Therefore, when converting the program, this type of special address needs to be assigned to all axes together. For example, D8148 of 3V is the acceleration and deceleration time of 4 axes Y0~Y3, then in LX5V, Y0 acceleration time SD902, deceleration time SD962 and other axis acceleration and deceleration time need to be set to the value of D8148.

2. Comparison of bit devices

3. Comparison of word devices

4. New features of high-speed pulse instructions on LX5V

①Support lower frequency output

3V: 10hz-200KHZ 5V: 1HZ-200K

②Support a larger range of acceleration/deceleration time, separate acceleration/deceleration

3V: 50ms-5000ms 5V: 15ms-32000ms

③Support to directly set the start frequency

④Support to modify the pulse frequency during operation

⑤Support to modify the pulse position (number) during operation

⑥Support direction delay (first output the direction and then delay and then output the pulse)

⑦Support positive and negative limit

⑧Provide different stopping methods (deceleration to stop or immediate stop)

⑨Support direction reversal (can set the forward direction to low level)

7 Communication function

1. Communication parameter configuration

There is a difference in the serial port parameter settings, mainly in the start bit of STX and ETX of the custom protocol. 3V is B8 B9 and 5V is B10 B11. The main reason is that 5V increases the baud rate of 921600.

2. Differences in protocol settings

3V settings:

5V settings:

Although 5V does not have 3V HMI monitoring protocol. But the current HMI has matched the 5V Wecon Modbus slave protocol. The Wecon Modbus slave protocol is modified based on ModbusRTU slave,  Compatible with all ModbusRTU slave content.

3. Differences in special devices

3V only supports setting the serial port parameters in the first cycle of the scan cycle. The mode of the first cycle setting can be switched only by modifying the corresponding soft element setting according to the special soft element comparison table.

4. Slave address difference

5V address:

5. LX5V added functions

Modify serial communication parameters during RUN. For example, use PROTOCOL instruction to modify the protocol during run. The corresponding instruction description can also find the method of setting without instruction. For details, please refer to the relevant instructions of the instruction. Commands are PROTOCOL (set serial port protocol), PROTPARA (set serial port parameters), STATION (set station number)