SainSmart USB Eight Channel Relay Board for Automation - 12 V

I purchased this to switch contacts in a data acquisition setup. It works well, all relays function correctly. The 'Relay Manager' program that you can download from the link (and their website) works perfectly. I am having only one issue. I am using LabVIEW to control the board and I cannot get the given (from the download link) library files to open the board. That is, I can run the Open file and get an OK error status in return (it will return various error statuses, depending on the result) but the board will not actually open. I can get the device description, location and handle, but no communication connection. I tried a USB sniffer to check the data going over the port but couldn't seem to find what I was looking for. I contacted the company and was given all the information that I already had. They were very prompt and courteous, but no real help. I never spoke with a programmer, only a secretary or some such. The problem may be with LabVIEW but seems to be some command that I don't know since I can send other commands correctly. I am running Windows 7 and that may be an issue since the library files were written several years ago, although they have stated that they are compatible with this version of Windows and I am not having any other problems. Anyway, my solution (until I can figure out what to do) is to open the board with the 'Relay Manager' and then send commands to the board as I like using my LabVIEW program. I only have to open the board once until I restart my computer and can close the Relay Manager (the initial handshake, whatever it is, remains) and open and close LabVIEW as often as I like with no problems. Now, I had to experiment to find the commands to turn the relays on and off because I could not get their supplied commands to work. I tried and tried and might try some more later but I found what I need through trial and error so it's not an urgent issue right now. As an example, the company said to use FF 01 01 to turn on channel 1. I couldn't get that to work and use 11 instead. So, since the problem seems to be with my programming (although the given D2XX commands don't list anything to cover how to get an initial handshake and I have installed all of the necessary .net files and various drivers) I know that the board works (since their program works well) and I have found the commands to do what I want... I will give it five stars. The board is capable of allowing interface with external switches and will be very useful once I figure out how to get full control over it. edit: For those that are interested, I found the commands for this board (chip). I got a little time and decided to make a program like the one that is provided by the company. I was (once again) trying in vain to get their commands to work and finally just decided to try everything. Well, it turns out that it's pretty simple. After various combinations I found that the on/off state of the switches (relays) are simply represented by binary code from 0 to 255. That is, 00000001 (1 decimal, 01 hex) gives relay #1 on (rest off); 11111111 (255 decimal, FF hex) gives all relays on; 00101101 (45 decimal, 2D hex) gives relays 1, 3, 4, 6 on and the rest off; etc. Also, the communication problem was likewise easily fixed with a little attention to detail. Have fun.

set this up for dof with my virtual pinball table. works easily. if you have issues with it disconnecting check the solenoids you are working.

This board works great. I was able to use LabView to configure the board to do bit bang mode. From there, you just write a byte of data to it. Each bit in that byte of data represent a relay. 1 turn it on and 0 to turn it off. All the FTDI functions VIs are supplied by the FTDI chip Vendor, and two examples are given. Overall, the board is nicely built, very rugged. It works as advertised.

Seems to work ok, but impossible to get it working on a Mac with Catalina (and maybe Mojave), because Mac OS X doesn't let you manipulate HID devices. Works fine with the supplied Windows executable, but the "send 0xFF, channel, state" approach doesn't work. You can make it work with Linux - libusb, and so forth. A significant problem is that the relay coils are operated off the 12V source - which is sort of fine, but if you have a load that kicks out significant transients (i.e. another relay), you will fry the output side of the relay drivers or worse, your computer's USB interface. It's still recognized by the computer on the USB side, but the relays don't actuate (nor do the tally LEDs illuminate). Still seems to be an OK device, but needs some sophistication in use that's not described in any of the user docs (which are incredibly sketchy.. they don't even tell you which terminal is which on the relay).

The USB_Relay program works OK with this board although rather simple. However, serial port apps such as HTerm cannot communicate, nor any home written version. Surprisingly, if you run the original program first then terminate, other programs work. But, the protocol is not like any instruction found. You would expect the code to look like "xFF x04 x01" to turn on relay 4. That does not work. The board uses a bit-bang method. To turn on relays 1, 5, and 8, you would send b10010001 or x91. Either method is fine but the board cannot be initialized by any published method. It appears that the original app does some initializing by direct USB. Until that happens, then board is useless for home brew code. Follow-up, 6-13-23 From an electrical and functional point of view, the board is superb. The operational software is the present shortcoming. The board appears as a serial port in the device manager but does not respond to any commands. The board has to be in bit-bang mode to operate. There are several ways of dealing with this issue. First, use the software app from the SS support site. It's a stand-alone copy of the Denkovi app and works fine. Second, use their app to open the board then close the app. This leaves the board in the correct mode while still powered on the USB side. Thereafter, you can use a terminal app like HTerm or your own. Finally, I was able to create a more functional app in Lazarus/Pascal by using direct calls to the FTDI DLL library to put the board into the proper mode. Once it's in a usable mode, it's one of the best. I was in contact with SS tech support on many occasions. They did their best to help but the information is just not available. I gave them suggestions for serial communications that is used on other brand boards. This is a 3-byte set sent in binary. The set is 0xFF 0x0n 0x0s where "FF" awakens the board for possible baud value determination, "n" is the relay number(1-8), and "s" is the status condition(1-on/0=off). This is being considered for a future update. The bit-bang scheme will be left intact for backward compatibility. For all my efforts, SS sent me a free board. I'm now working on the idea of using two boards with multiple instances of my app. 73 from KF4JU

The very sparse documentation is confusing, so you'll find you get more information by reading reviews from the people who have the board working. Those people are very helpful, but even with their solutions the board did not work for me. Even the "Board Manager" software supplied by SainSmart fails to recognize this board and control it.

Excellent product and works perfectly with my Flex 6300 for automatic band switching control on the Dunestar 600! This is a high quality PCB and very well constructed. Just ordered another to build an automatic remote coax switching unit. No way that I could even buy the components to build my own at this crazy low price!

Great Board for Pinball Cabinet

Purchased for use with a virtual pinball cabinet. This is the 8 relay usb board that is recognized by the DOF software. The board comes with no manual, so you will need to go to Sainsmart’s website to get the driver and manual (the driver is in the same zip file as the manual). Everything worked perfect upon the driver install in windows10, and now i have 8 channels to plug in force feedback devices. Don’t forget to wire in diodes to any solenoids or contactors you hook up to this board or you will get flyback voltage which will cause usb disconnects.

As described

Board is not very thick and mounting holes are too close to the site terminals so it's very difficult to secure. More importantly, they don't include a USB cable and make no mention of this in the description! Feels misleading when I need to spend another $20cad

garbage DO NOT BUY when you power on it toggles all channels multibul times can and will cause damage