Need an advice

Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
Basically I have a VFD tht is impossible to get ( mostly due to price and age )
It has LAN comm port. So I am thinking that the console is sending the command through it and also it is the only one connected to console.

I am looking for a work around.
I need to read the data coming from the console. If it is analogue, OK I can check. But if it is MODbus then I need to see the data.

What equipment is best. I am thinking logic analyzer.
What do you say ?
 

MrSalts

Joined Apr 2, 2020
2,767
A digital scope can capture the words sent to the VFD - usually a command word plus a value word. The VFD is likely sending data requests to the VFD like, get RPM or GET current draw or even, get rotational position by passing a register number from controller to VFD. The value will be. clocked out from the register on the VFD to the controller. The controller will then decide what to do. For example, increase duty cycle if rotation is not what is expected, or wait longer for motor to come to a compete stop.
 

MisterBill2

Joined Jan 23, 2018
19,419
That VFD assembly quite probably has a logic IC on the PCB beneath the display, because the actual VFD is a multi-segment device with no internal logic capability, Usually the interface consists of a DC power connection, an AC heater connection for the first generation, a data common line, a data line, and usually a data clock line. The data is usually sent in a string, one character position at a time, in sequence. Interpreting it on a digital scope is certainly possible, easier if you have a idea as to what is being sent. A logic analyzer might be more convenient but not a lot better.. It still will require a lot of thinking.
 

Irving

Joined Jan 30, 2016
4,049
Hmmm... Is VFD =" Variable Frequency Drive" from @MrSalts post #2, or "Vacuum Fluorescent Display" from @MisterBill2 post #5 - its difficult to say from the TS' original post, but if I had to guess I'd go with the first one as makes marginally more sense...:rolleyes:
 

MisterBill2

Joined Jan 23, 2018
19,419
Another option could be a "com" port on a computer. That might be even an RS232 port.
I am familiar with communicating with displays, that is not how I communicated with Variable Frequency Drives .(This is wy abbreviations and acronyms are a poor choice to start a discussion. If it is a drive then there may be some information available from a manufacturer about the communication format, if that manufacturer is still around.
If it is a display, prior suggestions hold.
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
VFD to drive the motor.
This bloody thing does not have a display or buttons to enter parameter. So programing is not possible. And searches reveal nothing. My only option is to identify console command and use another VFD programmed to those control commands.
 

MisterBill2

Joined Jan 23, 2018
19,419
OK, so the "thing" is a variable speed drive, So now for a guess that it is attached to a machine of some sort that would perform some sort of action powered by a motor driven by the nameless variable speed drive. That is my guess now.
Most variable speed drives that program externally have been manufactured by a company with a name, and on many occasions others may have some insights as to how to locate information. I have observed that among the folks who answer questions posted on this site are a whole lot of folks who possess a whole lot of experience, and many of them are quite willing to share what they know. I have also observed that the majority lack one handy skill,which I also am unable to use, which is mind-reading at a distance. And quite a few folks are unwilling to spend time making random guesses that are probably unrelated to the questions not asked.
Knowing neither brand, producer, application, or any other details I fall into that segment of persons.
 

strantor

Joined Oct 3, 2010
6,837
VFD to drive the motor.
This bloody thing does not have a display or buttons to enter parameter. So programing is not possible. And searches reveal nothing. My only option is to identify console command and use another VFD programmed to those control commands.
Is your link, a link to the actual VFD? Or just a link to show that you're talking about a Variable Frequency Drive?

Industrial devices often have RJ45 ports that are not ethernet ports. They might use an RJ45 port that send out power and serial comms for a remote keypad or something else.. If you do not know for a fact that it is an ethernet port, then do not risk plugging a computer or anything else into it; you could damage the VFD and/or whatever you plug in. But if you do know that it is an ethernet port, you can insert a network switch between console (whatever that is you're calling console) and the VFD. Then plug your computer into the same network switch and run Wireshark. It will tell you what protocol is being used and show you the data exchange.
 

strantor

Joined Oct 3, 2010
6,837
If that was actually the VFD in the alibaba link then it is NOT an ethernet port (or LAN comm port as you said). It has GND on 3 pins, +8V on 3 pins, and serial comms on the other two. DO NOT plug any ethernet device into it. If you scope the rx/tx pins it will at least tell you the voltage levels which you can use to determine what kind of serial comms it's using. It may be possible to read the bytes exchange with a USB>serial device depending

Screenshot_20230218-160245_Drive.jpg
 

MisterBill2

Joined Jan 23, 2018
19,419
There was an era when an RJ45 connector was used for an RS232 connection because it occupied much less room. I still have a number of those 25 pin "D:" style connectors with an RJ45 in the backshell. Also some 9 position "D"style connectors like that. They worked for programming some proprietary test machines for a major auto company.

And we still have no hint about whatever drive the TS is raging away about..
 

MaxHeadRoom

Joined Jul 18, 2013
28,825
I need to read the data coming from the console. If it is analogue, OK I can check. But if it is MODbus then I need to see the data.
Most of the VFD's I have worked with have a Modbus RS485 port. My laptop has a RS232 so I just use a simple cheap convertor and free RS232 port read/write program to test and set up the unit.
What is the application and make/model of VFD?
 
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Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
If that was actually the VFD in the alibaba link then it is NOT an ethernet port (or LAN comm port as you said). It has GND on 3 pins, +8V on 3 pins, and serial comms on the other two. DO NOT plug any ethernet device into it. If you scope the rx/tx pins it will at least tell you the voltage levels which you can use to determine what kind of serial comms it's using. It may be possible to read the bytes exchange with a USB>serial device depending

View attachment 287857
Damn @strantor
You nailed it . What I showed was the actual one I have in the link. Actually I have 2 units. Same PCB but different labels. Program is not compatible.
What you showed is what I have been searching for quite a some time, I really dunno how you got it. Based on your info I think I can figure the TX/RX
 

strantor

Joined Oct 3, 2010
6,837
Damn @strantor
You nailed it . What I showed was the actual one I have in the link. Actually I have 2 units. Same PCB but different labels. Program is not compatible.
What you showed is what I have been searching for quite a some time, I really dunno how you got it. Based on your info I think I can figure the TX/RX
The alibaba listing said "Inverter for Precor 966i." I didn't know what that was so I googled Precor 966i and found that it is a treadmill which uses a 3ph AC motor instead of the normal DC motor. So I searched "Precor 966i inverter service manual" hoping to find some mention of the port and hopefully also about programming software. I did find the (treadmill) service manual but unfortunately it didn't say anything about programming. If parameters can be changed in the drive, it is probably only done in the factory. I think that port is only for transmitting speed and elevation command from the treadmill console. If you can replicate these commands you can probably use the VFD for other purposes but I will be surprised if you can find a way to change parameters.
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
Most of the VFD's I have worked with have a Modbus RS485 port. My laptop has a RS232 so I just use a simple cheap convertor and free RS232 port read/write program to test and set up the unit.
What is the application and make/model of VFD?
My guess was Modbus.
How do you go about reading the data.
What is shown in the link is what I have and another same thing with hyundai N700E label. Hyundai does not show this type, so I am lost.
VFD is used in treadmills. I need to replace this with another type that is cheaper.

Do you have any pointer
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
The alibaba listing said "Inverter for Precor 966i." I didn't know what that was so I googled Precor 966i and found that it is a treadmill which uses a 3ph AC motor instead of the normal DC motor. So I searched "Precor 966i inverter service manual" hoping to find some mention of the port and hopefully also about programming software. I did find the (treadmill) service manual but unfortunately it didn't say anything about programming. If parameters can be changed in the drive, it is probably only done in the factory. I think that port is only for transmitting speed and elevation command from the treadmill console. If you can replicate these commands you can probably use the VFD for other purposes but I will be surprised if you can find a way to change parameters.
That is a lot actually.
Thanks buddy
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
I do not need to change the parameter of this expensive thing. I need to study how to use the data to run a another cheaper VFD's
 

strantor

Joined Oct 3, 2010
6,837
I do not need to change the parameter of this expensive thing. I need to study how to use the data to run a another cheaper VFD's
Oh. In that case, you may get lucky and find that this thing is using Modbus but I will be very surprised if that is the case. Modbus is what you use when you want your device to play nice with other people's hardware. Like if you're Schneider and you want your VFD to be able to communicate with PLCs from Omron, Mitsubishi, or anyone else - then you go to the effort of programming in support for Modbus in your VFD. Since this is designed for use exclusively with this particular treadmill, I doubt they went to the effort. I would expect to find a proprietary, undocumented protocol that, with enough time and effort you can probably reverse engineer, but probably won't be worth your time and will require an intermediate device (PLC, Arduino, etc) to translate this protocol to modbus or other common industrial protocol.

But I could be wrong and this could be easy. Even if not, in my mind you are just stubborn enough to make this work even if it isn't easy. So I will be watching this thread with interest to see where you go with it.
 

Thread Starter

R!f@@

Joined Apr 2, 2009
9,919
I need to find away. We have quite a lot actually of these.
I fixed a few but this one particularly refuse to work. I going to give it a go as soon as I get new IPM/IGBT for the current broken one.
I really dunno how long the cracking will take place but I will give it a go as time permits.
I read that these particular ones have different firmware for different treads. So it cannot be swapped unless tread model matches

I say this cause sellers need the tread model to program firmware before shipping
 
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