I've searched and can't find any guidance.

I have a holiday home a few doors away, with some solar panels, an
inverter and an EM24 DIN energy analyser.

I also have a Raspberry Pi sitting doing nothing.

I want to be able to monitor leccy usage via a web page on the pi (using
a wireless dongle as that house isn't wired for ethernet).

I have no idea where to begin.

Anybody here feel qualified (and willing) to help?

Cheers.

--
Paul.

https://paulc.es

El Mon, 25 Mar 2024 15:19:56 +0000, Paul Carmichael escribió:

> I've searched and can't find any guidance.
>
> I have a holiday home a few doors away, with some solar panels, an
> inverter and an EM24 DIN energy analyser.
>
> I also have a Raspberry Pi sitting doing nothing.
>
> I want to be able to monitor leccy usage via a web page on the pi (using
> a wireless dongle as that house isn't wired for ethernet).
>
> I have no idea where to begin.
>
> Anybody here feel qualified (and willing) to help?
>
> Cheers.

It looks like a starting point may be installing the victron venus app on
the pi. It seems that it should recognise the EM24 as a device and
present it on a web server.

--
Paul.

https://paulc.es

On 25/03/2024 15:19, Paul Carmichael wrote:
> I've searched and can't find any guidance.
>
> I have a holiday home a few doors away, with some solar panels, an
> inverter and an EM24 DIN energy analyser.
>
> I also have a Raspberry Pi sitting doing nothing.
>
> I want to be able to monitor leccy usage via a web page on the pi (using
> a wireless dongle as that house isn't wired for ethernet).

Maybe start by looking at something like this:
<https://www.ebay.co.uk/itm/295918558814>
Cheap and connects to your phone.

There is a thread on one of the Pi forums about what you want. It doesnt
sound particularly easy, but when configured, will give more info. Your
Inverter may have the output and input details readily available for
export to your Pi via some interface, but you'd need to search for your
make and model to see what it can do.
<https://forums.raspberrypi.com/viewtopic.php?t=353546>

El Mon, 25 Mar 2024 15:19:56 +0000, Paul Carmichael escribió:

> I've searched and can't find any guidance.
>
> I have a holiday home a few doors away, with some solar panels, an
> inverter and an EM24 DIN energy analyser.
>
> I also have a Raspberry Pi sitting doing nothing.
>
> I want to be able to monitor leccy usage via a web page on the pi (using
> a wireless dongle as that house isn't wired for ethernet).
>
> I have no idea where to begin.
>
> Anybody here feel qualified (and willing) to help?
>
> Cheers.

Heh. My investigation so far has led me to the pen of a certain John
Rushworth.

--
Paul.

https://paulc.es

El Mon, 25 Mar 2024 15:39:04 +0000, Alan Lee escribió:

> On 25/03/2024 15:19, Paul Carmichael wrote:
>> I've searched and can't find any guidance.
>>
>> I have a holiday home a few doors away, with some solar panels, an
>> inverter and an EM24 DIN energy analyser.
>>
>> I also have a Raspberry Pi sitting doing nothing.
>>
>> I want to be able to monitor leccy usage via a web page on the pi
>> (using a wireless dongle as that house isn't wired for ethernet).
>
> Maybe start by looking at something like this:
> <https://www.ebay.co.uk/itm/295918558814>
> Cheap and connects to your phone.
>
> There is a thread on one of the Pi forums about what you want. It doesnt
> sound particularly easy, but when configured, will give more info. Your
> Inverter may have the output and input details readily available for
> export to your Pi via some interface, but you'd need to search for your
> make and model to see what it can do.
> <https://forums.raspberrypi.com/viewtopic.php?t=353546>

Nothing found so far. It's an Ingecon sun lite.

Looking at connecting the pi to the wattmeter, I see that the inverter
also connects using the same connectors. I don't know why the inverter
needs to know this stuff, unless it has something to do with the fact
that it switches itself off if the mains goes down. Whether a pi can also
be connected to the same pins at the same time, I have no idea.

--
Paul.

https://paulc.es

Paul Carmichael <wibbleypants@gmail.com> wrote:
> I've searched and can't find any guidance.
>
> I have a holiday home a few doors away, with some solar panels, an
> inverter and an EM24 DIN energy analyser.
>
> I also have a Raspberry Pi sitting doing nothing.
>
> I want to be able to monitor leccy usage via a web page on the pi (using
> a wireless dongle as that house isn't wired for ethernet).
>
> I have no idea where to begin.
>
> Anybody here feel qualified (and willing) to help?

I could probably give you a few pointers if not devise a solution for
you, I've done a bit of this sort of thing using an RTL-SDR radio
dongle hooked up to various Raspberry Pis to listen to my smart
electric and water meters.

I briefly googled the "EM24 DIN energy analyser" and the first spec
sheet I came across said it has a Modbus RS-485 interface. Very
doable to interface that to a Pi, although you will need some sort
of interface "HAT", or possibly a USB->RS485 converter.

El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:

> Paul Carmichael <wibbleypants@gmail.com> wrote:
>> I've searched and can't find any guidance.
>>
>> I have a holiday home a few doors away, with some solar panels, an
>> inverter and an EM24 DIN energy analyser.
>>
>> I also have a Raspberry Pi sitting doing nothing.
>>
>> I want to be able to monitor leccy usage via a web page on the pi
>> (using a wireless dongle as that house isn't wired for ethernet).
>>
>> I have no idea where to begin.
>>
>> Anybody here feel qualified (and willing) to help?
>
> I could probably give you a few pointers if not devise a solution for
> you, I've done a bit of this sort of thing using an RTL-SDR radio dongle
> hooked up to various Raspberry Pis to listen to my smart electric and
> water meters.
>
> I briefly googled the "EM24 DIN energy analyser" and the first spec
> sheet I came across said it has a Modbus RS-485 interface. Very doable
> to interface that to a Pi, although you will need some sort of interface
> "HAT", or possibly a USB->RS485 converter.

Yup. I'd seen that. I was aabout to burn the venus OS onto the Pi (seems
it is already configured to "see" the em24) when I realised that the
rs485 terminals are actually connected to the inverter. Might connecting
the Pi to them as well somehow affect the functionality of the inverter?

PS: This morning I only see this reply and not the original thread. Maybe
it's a Pan thing.

--
Paul.

https://paulc.es

Paul Carmichael <wibbleypants@gmail.com> wrote:
> I've searched and can't find any guidance.
>
> I have a holiday home a few doors away, with some solar panels, an
> inverter and an EM24 DIN energy analyser.
>
> I also have a Raspberry Pi sitting doing nothing.
>
> I want to be able to monitor leccy usage via a web page on the pi (using
> a wireless dongle as that house isn't wired for ethernet).
>
> I have no idea where to begin.
>
> Anybody here feel qualified (and willing) to help?

For software, have a look at Home Assistant. It's primarily intended for
controlling stuff ('WHEN solar is generating THEN ...'), but there's an
energy monitoring function too. It gives you a webby GUI for seeing what's
going on.

There is Modbus support, so it should talk to the Pi via a USB-RS485
adapter. Somebody has done a HA config for the EM24:
https://community.home-assistant.io/t/modbus-with-carlo-gavazzi-em24/353336/2

There are other projects which are more focused on logging rather than
controlling things. https://openenergymonitor.org/ is one. They also sell
hardware if what you have isn't sufficient.

Theo

Paul Carmichael <wibbleypants@gmail.com> wrote:
> El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:

>> I briefly googled the "EM24 DIN energy analyser" and the first spec
>> sheet I came across said it has a Modbus RS-485 interface. Very doable
>> to interface that to a Pi, although you will need some sort of interface
>> "HAT", or possibly a USB->RS485 converter.
>
>
> Yup. I'd seen that. I was aabout to burn the venus OS onto the Pi (seems
> it is already configured to "see" the em24) when I realised that the
> rs485 terminals are actually connected to the inverter. Might connecting
> the Pi to them as well somehow affect the functionality of the inverter?

Modbus RS-485 is a multi-drop bus, so it's possible to have multiple
devices attached. Presumably whatever interface you would be putting
between the Pi and the EM24 is only going to listen, it should not
disrupt the signaling between the analyzer and the inverter. Whether
you can get the info you want without the Pi actively talking TO the
EM24 is another question.

Theo gave some excellent answers, I've dabbled with HomeAssistant,
you might look into their Reddit group or their developers forum to
see if anyone there has done anything to interface to the EM24.

Otherwise I think the best way forward is to just ignore the EM24
and attach current sensors to the circuits you want to monitor,
and use whatever app/web interface they work with.

El Tue, 26 Mar 2024 13:27:03 +0000, Theo escribió:

> Paul Carmichael <wibbleypants@gmail.com> wrote:
>> I've searched and can't find any guidance.
>>
>> I have a holiday home a few doors away, with some solar panels, an
>> inverter and an EM24 DIN energy analyser.
>>
>> I also have a Raspberry Pi sitting doing nothing.
>>
>> I want to be able to monitor leccy usage via a web page on the pi
>> (using a wireless dongle as that house isn't wired for ethernet).
>>
>> I have no idea where to begin.
>>
>> Anybody here feel qualified (and willing) to help?
>
> For software, have a look at Home Assistant. It's primarily intended
> for controlling stuff ('WHEN solar is generating THEN ...'), but there's
> an energy monitoring function too. It gives you a webby GUI for seeing
> what's going on.
>
> There is Modbus support, so it should talk to the Pi via a USB-RS485
> adapter. Somebody has done a HA config for the EM24:
> https://community.home-assistant.io/t/modbus-with-carlo-gavazzi-
em24/353336/2
>
> There are other projects which are more focused on logging rather than
> controlling things. https://openenergymonitor.org/ is one. They also
> sell hardware if what you have isn't sufficient.

Thanks. I was looking at the Venus OS as it should give me what I want
out of the box according to:

https://www.victronenergy.com/upload/documents/
Energy_Meter_EM24_RS485/113406-Energy_Meters-pdf-es.pdf

--
Paul.

https://paulc.es

El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:

> Paul Carmichael <wibbleypants@gmail.com> wrote:
>> El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:
>
>>> I briefly googled the "EM24 DIN energy analyser" and the first spec
>>> sheet I came across said it has a Modbus RS-485 interface. Very doable
>>> to interface that to a Pi, although you will need some sort of
>>> interface "HAT", or possibly a USB->RS485 converter.

I presume this "Prolific Technology Inc, PL2303 serial port" won't be any
good? Swot I just found in a drawer.

--
Paul.

https://paulc.es

El Tue, 26 Mar 2024 15:17:07 +0000, Paul Carmichael escribió:

> El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
>
>> Paul Carmichael <wibbleypants@gmail.com> wrote:
>>> El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:
>>
>>>> I briefly googled the "EM24 DIN energy analyser" and the first spec
>>>> sheet I came across said it has a Modbus RS-485 interface. Very
>>>> doable to interface that to a Pi, although you will need some sort of
>>>> interface "HAT", or possibly a USB->RS485 converter.
>
> I presume this "Prolific Technology Inc, PL2303 serial port" won't be
> any good? Swot I just found in a drawer.

This looks a better idea:
https://www.amazon.es/Waveshare-Industrial-USB-RS485-Transceiving/dp/
B081NBCJRS/ref=sr_1_1_sspa?sr=8-1-
spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

--
Paul.

https://paulc.es

El Tue, 26 Mar 2024 15:07:30 +0000, Paul Carmichael escribió:

> Thanks. I was looking at the Venus OS as it should give me what I want
> out of the box according to:
>
> https://www.victronenergy.com/upload/documents/
> Energy_Meter_EM24_RS485/113406-Energy_Meters-pdf-es.pdf

This looks promising:

https://wibble.paulc.es/venus/venus_pi.png

On a pi.

--
Paul.

https://paulc.es

Paul Carmichael <wibbleypants@gmail.com> wrote:
> El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
>
>> Paul Carmichael <wibbleypants@gmail.com> wrote:
>>> El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:
>>
>>>> I briefly googled the "EM24 DIN energy analyser" and the first spec
>>>> sheet I came across said it has a Modbus RS-485 interface. Very doable
>>>> to interface that to a Pi, although you will need some sort of
>>>> interface "HAT", or possibly a USB->RS485 converter.
>
> I presume this "Prolific Technology Inc, PL2303 serial port" won't be any
> good? Swot I just found in a drawer.

Not unless the meter has an RS-232 serial port, no.

--
FJR1300A, GL1000, KLR650A6F, EX250J9A, DR200SE, Vespa Ciao

Paul Carmichael <wibbleypants@gmail.com> wrote:
> El Tue, 26 Mar 2024 15:17:07 +0000, Paul Carmichael escribió:
>
>> El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
>>
>>> Paul Carmichael <wibbleypants@gmail.com> wrote:
>>>> El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:
>>>
>>>>> I briefly googled the "EM24 DIN energy analyser" and the first spec
>>>>> sheet I came across said it has a Modbus RS-485 interface. Very
>>>>> doable to interface that to a Pi, although you will need some sort of
>>>>> interface "HAT", or possibly a USB->RS485 converter.
>>
>> I presume this "Prolific Technology Inc, PL2303 serial port" won't be
>> any good? Swot I just found in a drawer.

As per my other reply- that's a USB->RS-232 interface, not USB->RS-485.

> This looks a better idea:
[URL fixed]
> https://www.amazon.com/Waveshare-Industrial-USB-RS485-Transceiving/dp/B081NBCJRS

It's cheap enough that I'd take a chance on that, if you have
a software solution lined up. I've bought a couple Waveshare LCD
displays for the Raspberry Pi that have worked well for me.

El Tue, 26 Mar 2024 20:53:24 +0000, Mark Olson escribió:

>> https://www.amazon.com/Waveshare-Industrial-USB-RS485-Transceiving/dp/
B081NBCJRS
>
> It's cheap enough that I'd take a chance on that, if you have a software
> solution lined up. I've bought a couple Waveshare LCD displays for the
> Raspberry Pi that have worked well for me.

Ordered, along with wifi dongle. Apparently, I can just connect it up and
register it with the VRM, so I can monitor it from anywhere.

I'm sure there are cheaper and simpler options, but a man has to have a
project.

--
Paul.

https://paulc.es

Mark Olson <olsonm@tiny.invalid> wrote:
> Paul Carmichael <wibbleypants@gmail.com> wrote:
> > El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
> >
> >> Paul Carmichael <wibbleypants@gmail.com> wrote:
> >>> El Tue, 26 Mar 2024 01:04:38 +0000, Mark Olson escribió:
> >>
> >>>> I briefly googled the "EM24 DIN energy analyser" and the first spec
> >>>> sheet I came across said it has a Modbus RS-485 interface. Very doable
> >>>> to interface that to a Pi, although you will need some sort of
> >>>> interface "HAT", or possibly a USB->RS485 converter.
> >
> > I presume this "Prolific Technology Inc, PL2303 serial port" won't be any
> > good? Swot I just found in a drawer.
>
> Not unless the meter has an RS-232 serial port, no.

PL2303 is the USB to UART chip. It's quite possible to stick an RS485
transceiver afterwards to make a USB to RS485 dongle - you can't tell that
from software. But it would probably say that on the outside if it did
that, or be otherwise obviously different from a serial dongle.

(eg RJ45 is an RS485 connector type, but there are also Cisco routers and
such that use RJ45 for RS232, so the RJ45 doesn't tell you for sure)

Theo

Paul Carmichael <wibbleypants@gmail.com> wrote:
> El Tue, 26 Mar 2024 15:07:30 +0000, Paul Carmichael escribió:
>
> > Thanks. I was looking at the Venus OS as it should give me what I want
> > out of the box according to:
> >
> > https://www.victronenergy.com/upload/documents/
> > Energy_Meter_EM24_RS485/113406-Energy_Meters-pdf-es.pdf
>
> This looks promising:
>
> https://wibble.paulc.es/venus/venus_pi.png
>
> On a pi.

If you're in the Victron world that's not a bad way to go. I get the
impression their stuff gets a bit more bumpy when you start talking to
things that aren't made by Victron, but I have no experience myself.
No harm to try it and see how far you get.

Theo

El Wed, 27 Mar 2024 16:39:13 +0000, Theo escribió:

> Paul Carmichael <wibbleypants@gmail.com> wrote:
>> El Tue, 26 Mar 2024 15:07:30 +0000, Paul Carmichael escribió:
>>
>> > Thanks. I was looking at the Venus OS as it should give me what I
>> > want out of the box according to:
>> >
>> > https://www.victronenergy.com/upload/documents/
>> > Energy_Meter_EM24_RS485/113406-Energy_Meters-pdf-es.pdf
>>
>> This looks promising:
>>
>> https://wibble.paulc.es/venus/venus_pi.png
>>
>> On a pi.
>
> If you're in the Victron world that's not a bad way to go. I get the
> impression their stuff gets a bit more bumpy when you start talking to
> things that aren't made by Victron, but I have no experience myself. No
> harm to try it and see how far you get.

They sell EM24s, so should work.

--
Paul.

https://paulc.es

Theo <theom+news@chiark.greenend.org.uk> wrote:
> Mark Olson <olsonm@tiny.invalid> wrote:
>> Paul Carmichael <wibbleypants@gmail.com> wrote:

>> > I presume this "Prolific Technology Inc, PL2303 serial port" won't be any
>> > good? Swot I just found in a drawer.
>>
>> Not unless the meter has an RS-232 serial port, no.
>
> PL2303 is the USB to UART chip. It's quite possible to stick an RS485
> transceiver afterwards to make a USB to RS485 dongle - you can't tell that
> from software. But it would probably say that on the outside if it did
> that, or be otherwise obviously different from a serial dongle.
>
> (eg RJ45 is an RS485 connector type, but there are also Cisco routers and
> such that use RJ45 for RS232, so the RJ45 doesn't tell you for sure)

You're correct about the PL2303 being the USB to UART, but the chances
of what Paul C. happening to have an RS-485 version of one of these
lying about is slim to none, especially since it says "serial port"[1]
on it.

Another thing I learned before quitting the propellorhead game was
that serial interfaces come with a dizzying array of connectors, and
it's best not to assume _anything_ about what you've got without a
full data sheet. So you might actually encounter an RS-485 interface
with a DB-9 connector, or as you say, an RS-232 with an RJ-45.

I remember myself and another guy spending a couple of days
straight debugging a very expensive system that was late to ship
out, for another engineering group that used an RS-423/485 to RS-232
converter. The original design team had thrown in the towel and we got
called in as the supposed serial protocol pros (basically another set
of eyes). We ended up figuring out the transceiver was auto-switching
from receive to xmit a bit too early (or was it too late?) cutting
off the start bit of the next message packet. We got a nice dinner
out of that one. Tip of the hat to Dave C!

[1] Even though it's true that RS-485 and RS-232 are both serial
interfaces.

--
FJR1300A, GL1000, KLR650A6F, EX250J9A, DR200SE, Vespa Ciao

El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:

> Modbus RS-485 is a multi-drop bus, so it's possible to have multiple
> devices attached. Presumably whatever interface you would be putting
> between the Pi and the EM24 is only going to listen, it should not
> disrupt the signaling between the analyzer and the inverter. Whether you
> can get the info you want without the Pi actively talking TO the EM24 is
> another question.

There is a "lock" option to prevent the Pi from doing stuff. The venus
instructions say it should be unlocked to allow "automatic
configuration", whatever that is. I'm sure I don't want that. Actually, I
just read the instructions for connecting the inverter to the em24 and it
says once configured, leave it locked. So presumably it's one way
communication during use.

I'm a bit scared though, as there is currently a resistor between the
data terminals of the em24. I've read that it should only be necessary if
the cables are long, but wibble. So I don't know whether to leave it
there or not. What sayest thou?

--
Paul.

https://paulc.es

Paul Carmichael <wibbleypants@gmail.com> wrote:
> El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
>
>> Modbus RS-485 is a multi-drop bus, so it's possible to have multiple
>> devices attached. Presumably whatever interface you would be putting
>> between the Pi and the EM24 is only going to listen, it should not
>> disrupt the signaling between the analyzer and the inverter. Whether you
>> can get the info you want without the Pi actively talking TO the EM24 is
>> another question.
>
> There is a "lock" option to prevent the Pi from doing stuff. The venus
> instructions say it should be unlocked to allow "automatic
> configuration", whatever that is. I'm sure I don't want that. Actually, I
> just read the instructions for connecting the inverter to the em24 and it
> says once configured, leave it locked. So presumably it's one way
> communication during use.
>
> I'm a bit scared though, as there is currently a resistor between the
> data terminals of the em24. I've read that it should only be necessary if
> the cables are long, but wibble. So I don't know whether to leave it
> there or not. What sayest thou?

It's a terminator. I won't get into transmission line theory, I'd just
leave it there.

On 31/03/2024 12:29, Paul Carmichael wrote:
> El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
> I'm a bit scared though, as there is currently a resistor between the
> data terminals of the em24. I've read that it should only be necessary if
> the cables are long, but wibble. So I don't know whether to leave it
> there or not. What sayest thou?

As Mark says, it's harmless. I don't know anything about transmission
line theory, but it's there to prevent sharp transitions of the
electrical signal from bouncing back down the line.

I learned this the hard way: many years ago, someone had designed some
sort of I/O or remote controller with dual-port RAM that was on the end
of a long ribbon cable. I wrote the test software for it, and it kept
failing randomly, usually the very last byte in the RAM was corrupted.

I fitted terminator resistors (values based largely on guesswork and
what I'd seen elsewhere, I think) and the problem went away.

--

CHUMP #1 (CHarge Up Muppet)

Pip

El Sun, 31 Mar 2024 16:00:31 +0100, PipL escribió:

> On 31/03/2024 12:29, Paul Carmichael wrote:
>> El Tue, 26 Mar 2024 14:33:58 +0000, Mark Olson escribió:
>> I'm a bit scared though, as there is currently a resistor between the
>> data terminals of the em24. I've read that it should only be necessary
>> if the cables are long, but wibble. So I don't know whether to leave it
>> there or not. What sayest thou?
>
> As Mark says, it's harmless. I don't know anything about transmission
> line theory, but it's there to prevent sharp transitions of the
> electrical signal from bouncing back down the line.
>
> I learned this the hard way: many years ago, someone had designed some
> sort of I/O or remote controller with dual-port RAM that was on the end
> of a long ribbon cable. I wrote the test software for it, and it kept
> failing randomly, usually the very last byte in the RAM was corrupted.
>
> I fitted terminator resistors (values based largely on guesswork and
> what I'd seen elsewhere, I think) and the problem went away.

Thanks both.

--
Paul.

https://paulc.es

El Wed, 27 Mar 2024 09:34:39 +0000, Paul Carmichael escribió:

> El Tue, 26 Mar 2024 20:53:24 +0000, Mark Olson escribió:
>
>>> https://www.amazon.com/Waveshare-Industrial-USB-RS485-Transceiving/dp/
> B081NBCJRS
>>
>> It's cheap enough that I'd take a chance on that, if you have a
>> software solution lined up. I've bought a couple Waveshare LCD displays
>> for the Raspberry Pi that have worked well for me.
>
>
> Ordered, along with wifi dongle. Apparently, I can just connect it up
> and register it with the VRM, so I can monitor it from anywhere.
>
> I'm sure there are cheaper and simpler options, but a man has to have a
> project.

FAIL.

Conflict between pi and inverter. I can see the tx lights up on the
converter, so I suppose the pi is polling and the inverter doesn't like
this. It repeatedly shuts down, presumably thinking that the mains has
gone off.

Also, although the venus tells me there is an energy meter, there is no
data.

Back to the drawing board then. Perhaps I'll look at home assistant. Oh,
min pi 3. Mine's a 2.

I'll just clean the pool instead.

--
Paul.

https://paulc.es