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I am using a three-phase meter ED310 interfaced in M-Bus with the M-Bus-IP HWg-PWR energy meter. I am interested in knowing how the Tarif1-4 inputs are used, contacts 15-33-13. What tensions should be applied, what is the logic with which the tariffs are assigned and how many tariffs the meter has.
What are the S0 inputs (20 and 21) for and how are they used?
How do I interpret the three-phase counter M-Bus parameters?I try to give as many answers as possible to your questions, the meter manages 2 tariffs (Selectable by connecting inputs 13 or 33 with input 15). On the basis of the tariff chosen, the meter manages the energy metering on two different M-Bus registers (Registers 1001 and 1002).
The S0 terminals (Terminals 20 and 21) as indicated in the drawing on the manual correspond to the collector and emitter of an optocoupler. On this output a pulse is generated for each 0,1 Wh (10000 pulses per kWh).
As for the M-Bus parameters, here is the table with all the parameters published by the counter.
1001 Total Energy Tariff1 (TBC)
1002 Total Energy Tariff2 (TBC)
1003 Total back Energy Tariff1
1004 Total back Energy Tariff2
1005 Reset counter
1006 Mains Voltage Phase1 (TBC)
1007 Mains Voltage Phase2 (TBC)
1008 Mains Voltage Phase3 (TBC)
1009 Instant Current Phase1 (TBC)
1010 Instant Current Phase2 (TBC)
1011 Instant Current Phase3 (TBC)
1012 Instant Power Phase1 (TBC)
1013 Instant Power Phase2 (TBC)
1014 Instant Power Phase3 (TBC)
1015 Instant Power celkem
1016 Cos Fi Phase1
1017 Cos Fi Phase2
1018 Cos Fi Phase3
1019 Max Current Phase1
1020 Max Current Phase2
1021 Max Current Phase3
1022 Max Power Phase1
1023 Max Power Phase2
1024 Max Power Phase3
1025 Unknown!Thanks for the precise and comprehensive answers, but you must excuse my ignorance, I need more clarifications. I have an electronic background, but I have been dealing almost exclusively with IT for 20 years!
…il contatore gestisce 2 tariffe… I have not entered any contact between 13 and 15 or between 33 and 15 and I work with rate1 which I therefore imagine to be the default, is that it?
What is Total Back Energy?
What is the 10055 Reset counter and how is it used?
What is celkem 1015 Instant Power?
What is 1016 Cos Fi Phase1, 1017 Cos Fi Phase2, 1018 Cos Fi Phase3?From what I remember from electrical engineering, CosPhi was used to measure the ratio between active and reactive power, this phase shift is caused by inductive loads in the system. But how is it provided here, what unit of measurement does it have?
Why is Instant Power not equal to Instant Current multiplied by Main Voltage? For example at the time of writing I have a PC attached to a meter in phase1 and I read:
(1006) Main Voltage P1 = 226, (1009) Inst. Curent P1 = 0.736, (1012) Inst. Power P1 = 102, (1016) CosFi P1 = 61
In my opinion it should be: [Inst Power P1] = [Inst. Current P1] * [Main Voltage P1]. But this is not the case, in fact from the calculation I get 166,4 Watts instead of the 102 I read! How can this be explained?
Waiting for the answers on the meter, I have passed your question to my supplier, I can elucidate you on the calculation of the power. The CosPhi value measured by the counter is expressed as a number and represents the cosine of the phase shift angle between voltage and current.
CosPhi can have values between 0 and 1, the value returned by the counter I assume is to be understood as 0.nn. So as in your case the value of 61 is actually 0.61.
The product of the instantaneous voltage and current is the value of apparent power which is not affected by the phase shift angle between voltage and current. While the instantaneous power measured by the meter is the active power, that is, the one actually absorbed by your load. It is measured in watts and is calculated with the formula: P = V x I x cosØ.
So in your case we will have 226 * 0.736 * 0.61 which as a result has 101.46 which is the value indicated by the counter in the instant power field. In all this talk, not only the value of Cos Phi returns to me, which is very low. It would appear that you have a very inductive load, although a PC shouldn't have this phase shift. You could try a purely resistive load, a resistance electric heater to verify that the cos Phi approaches 1.
I have received information from the supplier:
The Total back Energy field indicates any energy supplied to the network if the meter is used in generation plants (Photovoltaic, Wind, etc.) and a double tariff is also managed for the energy produced.
The value of the register “1005 Reset counter 27” has been kept for backwards compatibility, it has no effect.
Depending on the model, the meter can manage up to 4 tariffs, your model has only 2. No connected tariff input means tariff 1. To activate tariff 2 connect pin 1 with pin 3.
Thanks for the info then we are okay because all the electrical power of the computer is supplied via a UPS!
CosPhi: I tried with a fully resistive load, a small soldering iron, and in fact the CosPhi was 100 (i.e. 1), so I would say that the measurement is consistent.
As for the PC that mounts an HD and 3 cooling fans, I don't know how to judge what the influence of the inductive load may be, which should be max 20W on the total 100W. I used a PC as an example of load because it is the object that most reflects the final load that I will have to monitor, ie a few dozen servers.
Googling a bit on the net I found that for computer equipment the CosPhi usually varies between 0,5 and 0,8 so it is completely normal, of course your energy manager is not happy as he could apply penalties for a high phase shift.
It all depends on how much PC consumption is compared to the rest, or rather how much is the total CosPhi of your user. I remind you that the use of UPS leads to eliminating the phase shift on the side of the electrical user.
Fantastic now just to be precise we fail to understand what the "1015 Instant Power celkem" size means plus I would point out to the producer that the Unknown Value label for CosPhi values 1016, 1017, 1018 should be corrected!
In addition, the various quantities shown on the display, their sequence and also their meaning in the various screens are explained too briefly in the meter manual! For example, now I am testing the functioning of the second tariff, but I cannot understand from the display which is the indication that should indicate that T2 is active and not T1!
… Update, I have short-circuited PIN1 (13) with PIN3 (15), but the selected tariff is always T1! I also tried with PIN1 (13) with PIN2 (33), but nothing changes, what am I wrong? This is probably why I did not understand if I had activated tariff T2 in fact I had not activated it and the signals on counter 1 where I wanted T2 were the same as Counter 2 where I did nothing.
Regarding the selection of the tariff, I have misinterpreted the information of the supplier and what is reported about the connection of the inputs in one of the previous messages is incorrect. The tariff selection inputs must be powered with a 220Vac, in practice you must bring the neutral to signal 15 (PIN3) and bring a phase to signals 13 (PIN1) and 33 (PIN2) according to the tariff to be selected. In your version of the meter you can only feed signal 13 to select tariff 2.
The size "1015 Instant Power celkem" of the meter indicates a translation error, so the supplier tells me but I am not clear what it means.
I have however reported to the supplier your considerations on the lack of clarity of the manual.
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