Itho Daalderop Base Cube, no connection

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_pm
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Itho Daalderop Base Cube, no connection

Post by _pm »

I do not get the connection between OTGW and Itho Daalderop Base running, hopefully you can help me in further debugging this.
(I bought the OTGW 2nd hand)

Hardware I use:
Opentherm interface hardware version v2.0 2018 by nodo-shop.nl with ethernet interface
Itho Daalderop HP Base Cube (with also a Cool Cube connected)
Itho Daalderop Spider thermostat
Firmware 5.8 (also tested an earlier version)

Base cube error
When connecting the OTGW the Base Cube reports an OpenTherm not detected error. I see other users who have succesfully setup an OTGW with same heating and thermostat.

Tests
I performed tests Slave interface and Master interface tests according to the debugging page on otgw.tclcode.com
(I was not sure whether I could also perform the other (voltage/power) tests with my hardware/hw version)

The slave interface seems to be functioning, I do see messages when the thermostat is connected (the thermostat itself seems to be in some error though, did not look into that (new activation required??))
The repeating message (every +/- second): T00030000 Read-Data Slave configuration: 00000000 0

When also connecting the boiler I do not see any additional messages, no Bxxxxxx as I should expect

Diagnostics firmware
Then I ran I also ran the diagnostics firmware (Version 1.3)
Test 1+2 ran fine (leds and thermostat timing)
Test 3 'bit timing boiler' does not give any output at all
Test 4 'delay symmetry' fails (I assume loop connection is : connecting pin1 of boiler to pin1 of thermostat connector and same for pin2 (also tested with pin1 to pin 2 (crossed). This reports an error "### Error: Interfaces don't appear to be looped"
Test 5 reports expected voltage levels (level 4) for thermostat but for boiler connection


Is there anything more I can do to analyze what's wrong in my setup? My current conclusion is this is caused by the hardware
hvxl
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Re: Itho Daalderop Base Cube, no connection

Post by hvxl »

That sounds like there is something wrong with the boiler interface of your OTGW. To diagnose, remove the PIC from its socket, make a loop between the thermostat and boiler connectors, apply power to the OTGW, and measure the voltages on points 1 through 7 indicated on the picture below (it's a picture of v2.8, but the components of the boiler interface stayed in pretty much the same position ever since before version v1). You can use the pin indicated by the white circle as your reference point (GND). Any other point connected to GND is also fine.

otgw.jpg
otgw.jpg (120.56 KiB) Viewed 1545 times

Next, make a connection between the purple circles (pin 3 and 5 of the PIC socket, in case you're colorblind) and measure all 7 points again. Finally, remove the purple connection and make the green connection (pin 2 and 14 of the PIC socket) and measure the points again.

The expected results are:
Test 1:
  • 0.7V
  • 16.5V
  • 15.8V
  • 1.9V
  • 0.5V
  • 1.0V
  • 0.0V
Test 2:
  • 0.7V
  • 16.5V
  • 16.0V
  • 5.3V
  • 1.0V
  • 1.9V
  • 2.5V
Test 3:
  • 0.7V
  • 5.4V
  • 4.8V
  • 2.0V
  • 4.6V
  • 1.1V
  • 0.0V
The values may differ a bit, but those are roughly the voltages you should find. Any big deviations you find will hopefully point to a bad connection, or damaged component.
Schelte
_pm
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Re: Itho Daalderop Base Cube, no connection

Post by _pm »

Thanks for your fast reply!

I performed the measurements you proposed, with X1 connected to X2 and after that adding the pin connections in the IC connector feet
An overview of 'your' (should be) values followed by my measured values:

Test 1:
0.7V / 0,65
16.5V / 1,42
15.8V / 1,38
1.9V / 0,66
0.5V / 0,3
1.0V / 0,66
0.0V / 0

Test 2:
0.7V/ 0,75
16.5V / 2,72
16.0V / 2,6
5.3V/ 0,8
1.0V /0,33
1.9V / 0,76
2.5V / 0

Test 3:
0.7V / 0,63
5.4V / 1,33
4.8V / 1,3
2.0V / 0,65
4.6V / 0,33
1.1V / 0,6
0.0V / 0

I see big differences in the bold part (the biggest difference in tests 1+2). And some smaller (but I guess relevant) differences in other measurements.
I checked the schematics and see these measurements are linked to the optocoupler pins. And due to the loop between X1/X2 there should be the higher voltages you specify I guess.

Based on the http://otgw.tclcode.com/debugging.html#interface I performed the X1/X2 terminal checks.
Without connections on X1/X2, the voltage on X1 is 22,1V, I do not measure any current there (which should be there according to the site).
When connecting X1 to X2 the voltage drops down to 2V which also does not seem right and is probably causing the issues.
I am not able to conclude which part/connection could be defective though.....
Hopefully you can point me in the good direction

Photo of the boiler part of the print
1683669183709_30perc.jpg
1683669183709_30perc.jpg (126.16 KiB) Viewed 1523 times
hvxl
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Re: Itho Daalderop Base Cube, no connection

Post by hvxl »

So you are saying the OTGW is unable to produce any current on its thermostat interface? Are you sure you measured correctly? On some multi-meters you have to plug the leads into different holes to do current measurements. Of course it is possible that there is a problem on the thermostat interface as well. But given that you also have no communication with the boiler, that would mean you have multiple problems. That would be quite unusual.

Unfortunately your thermostat is battery powered (if I read the manual correctly). Otherwise the fact that the thermostat works would provide an indication that it receives power from the OT interface. To determine if the low voltages you see are really due to a problem on the thermostat interface, can you do measurements 2 through 6 again with the boiler connected and using point 1 as your GND level? The OTGW doesn't have to be powered. The boiler interface gets its power from the boiler.

On the other hand, I can't come up with a single failed component or short-circuit that would produce the measurements you reported if the thermostat interface is working correctly. There would have to be multiple problems in that case as well. It's all very curious.
Schelte
_pm
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Re: Itho Daalderop Base Cube, no connection

Post by _pm »

Sorry for the very late response and thanks for great directions so far.
I got the following measurements (without PIC, without power supply)
Without otgw connected 23v on the boiler connection
With otgw connected 2,34v on the boiler connection
All measurements (1-6) all have 0 volts

Sounds like buying a second hand gateway was not a good idea....
_pm
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Re: Itho Daalderop Base Cube, no connection

Post by _pm »

I checked th bottom of the print and see bad soldering
Bad soldering
Bad soldering
IMG-20230605-WA0008.jpg (119.03 KiB) Viewed 1311 times
I am going to solder this and test again
_pm
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Re: Itho Daalderop Base Cube, no connection

Post by _pm »

After soldering I measured in all 3 situations again
Only test 3 differs
Test 3:
0.7V / 0,63
5.4V / 1,33
4.8V / 1,3
2.0V / 0,65
4.6V / 1,36
1.1V / 064
0.0V / 0

All other measurements are still the same :(
hvxl
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Re: Itho Daalderop Base Cube, no connection

Post by hvxl »

_pm wrote: Mon Jun 05, 2023 9:47 pm I got the following measurements (without PIC, without power supply)
Without otgw connected 23v on the boiler connection
With otgw connected 2,34v on the boiler connection
All measurements (1-6) all have 0 volts
At least that confirms that there is a problem in the boiler interface. It doesn't rule out the possibility that there is also a problem on the thermostat interface. But let's focus on the boiler interface first.

It doesn't make sense though that all measurements resulted in 0V. With 2.34V on the boiler connection, measurement 2 should be around 1V. Unless you didn't measure relative to point 1 as I instructed. If you measured against the main GND of the OTGW, then the results are meaningless. The boiler interface is optically isolated from the main part of the gateway, so the levels are floating. In the earlier measurements there was a connection between the two parts via the loop between X1 and X2. I suspect you missed that remark, because you mentioned measurements 1-6. Measurement 1 would mean you had to put both probes on the same pin. You would have noticed that that is a useless measurement. Of course the result is going to be 0V. This is why I only asked for measurements 2-6.
Schelte
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