Hi @matt
I believe the latest version of Mervis should be able to handle it better now; you can give it a go and see if it works properly with multi-character strings. For further information please get in touch with support@unipi.technology and/or Martin Kudláček instead, as I will be leaving unipi shortly.
It should be fixed in the latest Master development version on GitHub, but it may take a little while before the next release is done. You can test it out yourself by replacing the file as detailed above.
V případě potřeby lze také nastavit bytové pořadí, v případě jinak-endianového kódování které používají některé vzácnější zařízení.
Hi @Joerg!
This looks like a bug in EVOK. The /rest/wd interface should return it correctly, I'll fix this in the github repository shortly, but it may take a little while before it gets into a debian package.
Once the update appears on GitHub you may be able to update EVOK manually by overwriting your /opt/evok/lib/python2.7/site-packages/evok/evok.py with the new version, or you can wait until the next EVOK release.
Hello @PR-Reger,
The protection slightly differs between the first I/O group and the second, but broadly speaking it is protected against voltage spikes.
Here's the protection circuitry for the first I/O group (taken from a generalised description):
The protection circuit has 2 pairs of Schottky diodes, as you can see from the circuit schematic above. (The B-1000-2 is a newer version which is used in Axon and uses a transile instead)
The first protection pair opens at positive voltage over 18.2V and shorts with negative voltage over 0.2V. The maximum current which the circuit can withstand is 70mA, but the protection characteristic is strongly time-dependent – it can withstand significant currents (>1A) for under 1uS, but it will fail if the current is sustained longer.
The second protection pair then further limits the voltage to 10.5V, which is the maximum voltage that the measurement circuit is capable of measuring, but this is only intended to cover the difference between the 10.5V and 18V voltages, not to act as an external current protection if the first pair fails.
The protection is designed primarily against EMC interference; if the device is connected to a source of strong and persistent interference we recommend the use of other external protection, based on varistors and transiles.
For the second I/O group the protection is similar, but the measuring circuitry is much more complex (to provide greater accuracy) which does make it vulnerable to certain specific faults, e.g. if switched to a wrong measuring mode. I will confirm with my coworker, who is unfortunately not available right now, whether there may be any problems with the second group I/Os and provide a description of the protection circuitry later today.
I hope this helps, if you require more details don't hesitate to ask.
Hi @PhilesG!
That's good to hear, though a bit concerning that it doesn't work with all flash drives. I'm not sure what we can do about that, but we'll have a look at it again.
The size limit in the web interface is unfortunately inserted quite deep into the system; essentially it's the amount of memory-mapped drive space that is reserved for holding the file sent over the network. Which is also why the flash drive method works, as the file is instead stored on the drive.
At any rate - glad you managed to get it to work!
Hi @Martin-Trojan,
This is just one possible solution, but you can use a custom ST FunctionBlock with this code (use the name "DigitalMemoryMultiplexer" if you do use it):
FUNCTION_BLOCK DigitalMemoryMultiplexer
(*
EXTENDS //base type
IMPLEMENTS //interface type list
*)
VAR
previous_inp_1: BOOL;
previous_inp_2: BOOL;
previous_outp: BOOL;
END_VAR
VAR_INPUT
inp1: BOOL;
inp2: BOOL;
END_VAR
VAR_OUTPUT
outp: BOOL;
END_VAR
INIT
previous_inp_1 := inp1;
previous_inp_2 := inp2;
previous_outp := inp1;
END_INIT
IF inp1 <> previous_inp_1 THEN
outp := inp1;
previous_inp_1 := inp1;
ELSIF inp2 <> previous_inp_2 THEN
outp := inp2;
previous_inp_2 := inp2;
ELSE
outp := previous_outp;
END_IF;
previous_outp := outp;
END_FUNCTION_BLOCK
And connect it like this:
The DO_2_01 is set as DirectSwitch Trigger and the WEB_LIGHT_BUTTON is tied to a HMI Digital Setter. Whenever you are using DirectSwitch remember to set the Debounce value on the DI sufficiently high for your input device.
Again, there are many other options for doing this, including using two HMI elements on top of each other (Digital Indicator and Digital Setter).
Here is the project file, for reference: https://www.mediafire.com/file/1o8kq9iici2qc8g/ForumProject.7z/file
Hi @bubuche!
Could you please try to switch the relay by writing '1' to the file /sys/devices/platform/unipi_plc/io_group2/ro_2_01/ro_value? You can do this via the commands:
sudo su
systemctl stop evok
systemctl stop mervisconfigtool
systemctl stop mervisrt
echo "1" > /sys/devices/platform/unipi_plc/io_group2/ro_2_01/ro_value
If this does not work then unfortunately it most likely is due to a hardware fault.
I had a look at the testing logs for your unit, and it has passed tests without any problems, so, if the above does not turn the relay on, you may have to email support to arrange further steps.
Hi @bubuche,
I'll reply to both your questions. Apologies for taking a while, I have not been available over the Christmas period.
The upper board RS485/RS232 ports are accessible under /dev/ttyS(0-3) as opposed to /dev/extcomm/0/0. This is unfortunately a hardware limitation which we cannot work around easily.
If the LED light turns on then the relay should have continuity across it; the LEDs are controlled by the same circuitry as the output itself. If there is no change in continuity across the output it may be due to some sort of a hardware fault. I should note that digital (as opposed to relay) outputs are transistor-based, and will not make any noise. The relays should issue an audible click however. Could you please post a quick schema of your installation as well? LED lights in particular can have a very high inrush current, which a slow-blow fuse may not neccesarily catch.
I hope this helps
In theory it should work the same as any other extension we have, though we cannot guarantee it, since some devices deviate from the standard protocol in one way or another. Either way you will need to create a custom ModBus map, whether you are using Evok, Mervis or something else.
Hi @PhilesG,
The image .swu can unfortunately only be flashed on boot, i.e. by holding down the button during powerup while the image flash drive is inserted in the USB next to the Ethernet port.
The 256MB limit is baked into the SWUpdate web interface and cannot be changed, but the scripted on-boot flashing process will happily accept it.
To recapitulate, the update process is as follows:
I hope this helps
Now looking at it, it is the same page and version.
Unfortunately it's just badly worded, the HMI application is only used for legacy projects. "Web Site Definitions" is a specific feature which has been completely remade, and as such are not necessary in the new integrated HMI.
If you have a look at the tutorial I have linked above it has a simple step-by-step guide for creating an HMI from scratch in the latest version.
I will get in touch with our documentation team to see if they can help you further.
It appears that you might be using an older version of the IDE, as this is how the page looks like for me:
I am truly sorry for any inconvenience. Could you please mention which version you are using (you can find this information in "Help" - "About").
Here is a working tutorial for the latest version: https://kb.unipi.technology/en:sw:01-mervis:creating-simple-hmi-hidden
Could you please mention where you found the tutorial which mentioned a separate HMI application? Just so we can have it taken care of.
Yes, it does have the ability to make websites, all of our HMI is web-based.
Apologies, we'll try to get this sorted ASAP.
Hi @clueless,
The Mervis HMI interface is now included within the IDE program itself. I will pass it on to the people on the team taking care of the knowledgebase to get it updated. You should be able to find further instructions for it in the internal Mervis help manual (F1).