now the HP stoptand the input KSvolflow stays on 7857 while the flow now is 0
hmm, not sure what KSvolflow is reading. Could you copy a graph, is there an accumulating trend or is it more a square wave steppy type shape? as the heatpump turns on/off?
Hello Trystan,
Now I get some understanding I did some test.
Listing data from Mbus serial reading I select the data who chancing.
Then I make the them serial printing by next changes to test.
mbus reader data 2.pdf (43.1 KB)
#ifdef KAMSTRUP_302
Serial.print(F(",KSVolumeFlow:"));
Serial.print(decode_4byte_bin(55),1);
Serial.print(F(",KSHeatAv:"));
Serial.print(decode_4byte_bin(61),1);
Serial.print(F(",KSflowT:"));
Serial.print(decode_2byte_bin(73)*0.01,2);
Serial.print(F(",KSreturnT:"));
Serial.print(decode_2byte_bin(77)*0.01,2);
Serial.print(F(",KSkWh_fo15:"));
Serial.print(decode_4byte_bin(15));
Serial.print(F(",KSdeltaT_fo27:"));
Serial.print(decode_4byte_bin(27));
Serial.print(F(",KSheat42:"));
Serial.print(decode_4byte_bin(42));
Serial.print(F(",KSflowrate_fo49:"));
Serial.print(decode_4byte_bin(49));
Serial.print(F(",KSkWh_fo55:"));
Serial.print(decode_4byte_bin(55));
Serial.print(F(",KSdeltaT_fo81:"));
Serial.print(decode_4byte_bin(81));
Serial.print(F(",KSheat85:"));
Serial.print(decode_4byte_bin(85));
Serial.print(F(",KSflowrate_fo97:"));
Serial.print(decode_4byte_bin(97));
Serial.print(F(",KSdeltaT_fo98:"));
Serial.print(decode_4byte_bin(98));
Serial.print(F(",KSheat:203"));
Serial.print(decode_4byte_bin(203));
#endif
Loading the script and cheking a time whit out, start, running and stop off the heatpump.
I listed the serial monitor in a exel file and put the results in a print as I send hierby.
mbus reader seriele monitor 2.pdf (45.1 KB)
Hello,
After some testing I became the Mbus reading looking pretty good.
But by further testing I became no good figures for the electric consumption from the 3 CT.
Therefore I installed a kWh meter (IME Conto D4-pd) whit a pulse-output.
I connected this to the board but I become no results from Elster meter reading.
The R8 and C1 are mounted and I can measure that the input D3 is switching when I manual make pulses on X7.
Whit all these issues the Mbus give now no response anymore. I measured 24 volts on the Mbus connection, is that correct.
Now I have 3 questions.
-
- Any suggestions why the pulsmeter dos not react.
-
- Can I make a serial print for the CT meters for volt and current
-
- Is the 24 V on the Mbus connection correct.
Greetings all,
Given the progress above, i’ve had a Sontex 531 fitted as part of our Heat Pump install and having some difficulty getting any signs of MBUS life from it. The unit itself is working perfectly alongside it’s Superstatic 440 flow meter. I was careful to buy the MBUS variant (albeit second hand) and wondered if anyone could confirm.- either from the board or the label on front - that this definitely has an MBUS module onboard?
The emonpi is reading the SDM120 fine over MBUS using OEMs USB module and I’m just trying to isolate the issue by checking it’s nothing as daft as not having MBUS compatibility. I’ve not had any success in asking Sontex directly…
Many thanks
Ben
Hello @thedawnbefore looks fine, have you set the MBUS address? There’s a bit on how to do this here: Reading from multiple MBUS meters with the EmonHub MBUS interfacer - #5 by TrystanLea you should also be able to read what the address is on the Sontex LCD itself.
I assume the blank LCD on the Sontex is just the disconnected head unit?
Thanks Trystan, that’s helpful - I hadn’t seen your address script which I’ll definitely give a go. I’ve since sent the meter off for glycol calibration (which is why the head unit is blank( so will try this as soon as it’s back. Thanks.
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Hi Ben, did you manage to get your m-bus interface working.
Just for info the Sontex 531 menu system shows if the m-bus option is fitted. It is option 7 (configuration) - Options.
I am having the same problem of no data using the USB to m-bus adapter on the EmonPi. Unfortunately I get “no reply received” using Trystan’s py scripts.
Brian
Hello Brian, is your Sontex 531 powered with AC or battery? Is the baud rate and address in the emonhub config the same as that listed on the display?
Hi Trystan,
The 531 is AC mains powered. The baud rate and address on the display are the same as entered in the emonhub. I have also used your py script to check the meter is responding on the correct address - this also is unsuccessful.
I have also tried using a different cable to connect the meter to the USB interface.
Any ideas would be gratefully received.
Brian
Hi @TrystanLea ,
Could you provide any guidance on how I might diagnose the connection. I have discussed the problem at length with the Sontex distributor but I am getting no further forward.
Brian
@Brain1000 I spent many hours trying to get data from my 531 and never got further than “no reply received”. So just following along here to see if there are any new ideas.
Hello @Brain1000 @knightian. Sorry for not getting back to you sooner on this.
@paul_tanner also had trouble reading from the Sontex 531 using our MBUS reader and in the end went for a different brand that seemed to work without any issue. Paul suggested the issue may be due to the voltage produced by our MBUS reader being too low.
I have a Sontex 531 myself and it’s working fine and I tested another 3 of our MBUS readers this morning and they all worked fine as well. I’ve got a relatively short run of cable to the MBUS meter, it may be that the voltage drop across that is low enough. My Sontex is mains powered and I thought that was a factor but now Im not sure if that’s right.
Glyn has been testing another MBUS reader that has a better hardware design and we’ve decided to swap over to these instead of continuing to produce our own. We’d be happy to send out a couple of these new readers to see if that solves the issue for both of you. I will check with Glyn when we can get these for you.
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I’ve just ordered more of these new MBUS readers and put them in the shop:
I’m afraid there’s a 30 day lead time to get more stock of these new readers.
Please could you send the shop a support email so can get a pre-order placed for one of these new readers: [email protected]
Hi Trystan,
It’s good that this is a minority issue.
I’d be happy to test your alternative solution and return it afterwards.
I can’t really say why I went for the battery-powered Sontex. That
may have been a bad idea.
Best/ Paul
Quoting Trystan Lea via OpenEnergyMonitor Community
[email protected]:
@TrystanLea Many thanks from me too. My cable was quite long, so I tried shortening to just 10cm and unfortunately still nothing.
I’d be happy to try the new reader - perhaps I could exchange it for the two existing ones I’ve tried? I’ll message the support email. 
Did you mange to resolve this? We’ve now got stock of the mbus readers:
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