[Solved] APATOR AT-MBUS-NE-02 Pulse Cap: Capturing Pulses for Water Monitoring System

Hello everyone,

I am in the process of building a water consumption monitoring based on APATOR water meters. I have received two, brand new APATOR AT-MBUS-NE-02 pulse caps ordered from the distributor . They were made according to a standard configuration, viz:
e.g.: for water meter type JS-1.6-02: Impulse overlay AT-MBUS-NE-02 with:
- impulse output no. 1 - IB
(volume counting like a mechanical counter)
- Pulse output 2 - PR
(volume counting like a classic NK)
- pulse weight 1 dm3/imp

According to the documentation provided by the manufacturer:
http://www.apator.com/uploads/files/Produkty/...cyjna/pl-00061-2015-r-nakladki-at-mbus-ne.pdf

The overlay has an open drain (OD) pulse output /0.17A, 100V/. I have a problem "capturing" pulses from this overlay.

The schematic (thank you user @-Maciej_ Rak ) for connecting this overlay I used the same as in the ORNO-WE-501 1-phase meter already installed with me (works via Arduino Nano), as below :

.

However, with the difference that it is 3.3V instead of 5V (I am using Arduino Pro Mini 3.3 (battery power from 12V 7.2Ah battery + AMS1117 3.3V).

Current wiring diagram:

.

When I take a multimeter, I get a voltage value of 3.3V on the connection terminals of the cap (without connecting it), as soon as I connect the green wire (ground) and the brown or white wire of the cap, I immediately get 0V....

I should add that by "blowing" into the water meter, I can see that the counting mechanism of the "water meter mirror" is rotating, but there is no sign of any generated pulses on the multimeter or on the serial-monitor terminal of the Arduino itself. Could anyone help with the subject? I am yet to visit Apator service (Enbra in Krakow) maybe they can help with solving this puzzle with some other connection scheme, but maybe something else can be solved thanks to you ? Perhaps this is an easy problem to solve and I don't know how to spot it, I'm not an electronics technician, so thank you very much in advance for any hints you can give me.

Thanks and best regards,
Maciek

Hello!
Firstly we assume that this overlay is programmed as pulse outputs.
Notice that they write about a voltage of 100V and a current of 170mA and the resistance in the conducting state of the field effect transistor at 30 Ohm.
So by applying 3.3V through a 10 Ohm resistor you are not able to run this transistor.
The binary inputs of the building automation PLC usually operate at a potential of
24V DC, and here you would first have to evaluate these outputs from the overlay.
Good luck

Added after 6 [minutes]:

PS
Correction - this is about the 10kOhm resistor.

flajper wrote:

Hello!
Firstly we assume that this overlay is programmed as pulse outputs.
Note that they write for a voltage of 100V and a current of 170mA and the resistance in the conduction state of the field effect transistor at 30 Ohms.
So by applying 3.3V through a 10 Ohm resistor you are not able to run this transistor.
The binary inputs of the building automation PLC usually operate at a potential of
24V DC, and here you would first have to evaluate these outputs from the overlay.
Good luck

Added after 6 [minutes]:

PS
Correction - it's about the 10kOhm resistor.

Thanks for the tip @flajper .
I have it written in the order that the overlays have been configured exactly as I described in the subsections .
Actually, perhaps this is where the problem lies. I don't have much room to put in a second 12V battery and connect them in series, also I would like to avoid another inverter. I'm wondering if on a direct connection from the 12v battery there is a chance to excite this overlay? Any suggestions on modifying then the 10kOhm resistor itself? .

BTW, while browsing the web I came across the CELLBOX pulse recorder model SMET:
https://ftp.aquard.pl/strefaklienta/Dokumenta...lBOX-SMET/CellBOX-SMET_instalacja_pl-v1.5.pdf
https://ftp.aquard.pl/strefaklienta/Dokumenta...-SMET/Instrukcja%20obsługi%20CellBOX-SMET.pdf

It supports a number of pulse overlays, from various manufacturers, including the AT-MBUS-NE-02 that I own. You could say that it is widely versatile, the recorder itself powered wirelessly via a battery (LiSOCl2 3.6 V 13Ah). So there is a chance that this can be "fired up" on my setup .

Hello !
Evaluate this overlay using a small 12V bulb e.g. one from the dashboard from your car so that the current does not exceed 170mA.
Connect the circuit/circuit, plus 12V - bulb - white or brown wire from the cap and now
the green one to the minus of e.g. this battery.The transistor in the open state has 30 Ohm.
A circuit connected in this way should flash you this bulb as you simulate the flow through this meter.If it doesn't work then change the bulb to a lower voltage, or raise the supply voltage of this circuit to 24V. You can also use a meter to judge what is happening in such a circuit.
You write about accepting pulses but on your Arduino mini, and that only works on vol. 3,3V
There are GSM modems on the WWW for sending sum pulses.
You will need to use an optocoupler to connect such a counter w/ me.
Regards

Thanks @flajper ,

I contacted the manufacturer APATOR directly. I obtained information, despite the overlay is wired, the factory is in "sleep". It is necessary to apply a magnet to it for 5-10 seconds to wake it up. I also received confirmation that the above wiring diagram is correct and that supplying it with 3.3V and using a 10kOhm pull-up resistor is perfectly fine. Everything is working and charging as it should. Problem solved ! .

I contacted the manufacturer APATOR directly. I was informed that although the overlay is wired, it is factory "dormant". It is necessary to apply a magnet to it for 5-10 seconds to wake it up. I also received confirmation that the above wiring diagram is correct and that supplying it with 3.3V and using a 10kOhm pull-up resistor is perfectly fine. Everything is working and charging as it should. Problem solved ! .