RAK5802 + RAK19010 connector(s) is/are mechanically unreliable

[Oberon (Or Beron)]

Hi,

I bought a couple of sets of RAK4631 + RAK19010 + RAK5802 and I can say that they are working unreliably.

When I look at posts in this forum I can see that this is a repeated problem, for example:

RAK5802 Ground needed?

I am using a RAK5802 to communicate with an RS485 sensor probe. I have everything working great and I am able to pull the data from the sensor. However after a period of time, I begin to experience timeouts on the RS485 side. I’ve replaced boards, and wisblock items, and pretty much everything but this still randomly happens. Today once I got the failure notice, I decided to bring the device in and touch a ground to the ground pin on the RS5802 quick attach block and then my device started worki…

Serial1 in RAK19001 and RAK5802

I have successfully tested a code that uses the Serial1 gate between a RAK5005 (board), RAK11200 (Core), and RAK5802 (IO). When I implement the same code on RAK19001 (board), RAK11200 (Core), and RAK5802 (IO). Do the serial gates change between the Core and IO when I use a RAK19001? scenario 1 RAK5005 (base) RAK11200 (Core Slot) RAK5802 (IO Slot) scenario 2 RAK19001 (base) RAK11200 (Core Slot) RAK5802 (IO Slot A) I using Arduino BSP; in Windows 10. I don’t use any library to communicate w…

RAK5802 times out with RAK19011, RAK11200

Hi, I am trying to read data from a Modbus RTU slave using RAK5802 on a Dual IO RAK19011, but I only receive timeout errors. Using the example code from RAKWireless GitHub, I receive the following response when I call try to read from the coils: Request result: 0xE4, Mem:339847. In the Modbus library the example code uses, 0xE4 corresponds to EX_TIMEOUT = 0xE4, // Custom. Operation not finished within reasonable time I know the Modbus RTU slave is working correctly as I can read …

The common denominator is that when a RAK5802 is connected to a RAK190XX board the RS485 sometimes work and sometimes it doesn’t.

To make it work I need to physically press with my fingers the area above the connector on the RAK5802.

This issue can be easily tested and reproduced using 2 sets of RAK4631 + RAK19010 + RAK5802.
Simply connect them together as the getting started page suggests and run RS485 sender example on one and RS485 receiver on the other.
It might work right away and if so, wait a couple of hours. It never keeps working over night.

This is a serious issue for me and I can’t really tell if it is a problem on the RAK19010 IO connector side or the RAK5802 connector side. Maybe the problem is with the raisers for the screws near the RAK19010 IO connector ?

Like I said, posts on this forum prove this is a repeated problem withe RAK19010 + RAK5802.

1. Why is it working with older main boards ? (RAK5005)
2. Does it work with other main boards that support power modules ? (if so I will need to switch main board)

Thanks.

[beegee (Bernd Giesecke)]

Mechanically the RAK5005-O (EOL), RAK19007 and RAK19010 are identical, the only difference is the power slot on the RAK19010.

What power slot module are you using?
How is your sensor powered?
Are the grounds of the sensor and the WisBlock connected?

Can you give more details about “raisers for the screws near the RAK19010 IO connector”, I don’t know what you mean.

I have a working setup with a RAK19010, RAK19016 5-24V power module, RAK4631 and RAK5802 that works without problems with a RS485 soil sensor.

[Oberon (Or Beron)]

I’m using the USB power module (RAK19012), and I power it via USB that is connected to a computer.

I’m not using a sensor, I simply connect 2 sets of RAK4631 + RAK19010 + RAK5802 as suggested in the getting started page (here).

The quick start configuration can be used by you to verify and reproduce the problem (no need for an external RS485) device.

No grounds on a sensor since I use no sensor in this test.

By “raisers for the screws near the RAK19010 IO connector” I mean these (marked with red circles):

Maybe they are a few microns too high ?
When I press the RAK5802 above this connector with my finger it seems to work. As if there is a connector problem.

I ordered 1 set of RAK4631 + RAK19010 + RAK5802 4 months ago and 6 sets a few weeks ago.
All show the same behavior.
The first time I thought it is a fluke, but now I start to believe (after browsing through the forum) that it is a shared problem that others experience as well.

[beegee (Bernd Giesecke)]

These three screw points are to fix the RAK5802. Did you fix the RAK5802 with screws?

[Oberon (Or Beron)]

Of course I fixed it with screws, just like I did with the other modules (RAK4631 + RAK19012):

[beegee (Bernd Giesecke)]

Did you double check that the wires are placed well in the connector.
Personally I don’t like this “fast-connect” solution.
Make sure the wire insulation is removed long enough (~ 10mm) and the wires are complete inside the connector.

Can you take a close picture of the connector on the bottom of the module (the one that goes into the Base Board).

[Oberon (Or Beron)]

USB to RS485 dongle I use to test this issue:

Connector:

Other side:

Currently connected wires:

There is no gap between the RAK5802 board and the RAK19010 board … the connectors are connected as good as possible (I mean as little gap as the screw raisers and connectors force us to have).

[Oberon (Or Beron)]

My mistake,

I double checked with your Arduino RS485 sender/receiver examples and they work on all boards.
The problem seems to be in my code.

I’m sorry for misleading you.