Please help.

Have a Goodwe 4.6kw hybrid installed and recently had a conlog bec44 prepaid installed. The conlog disconnects on abnormal trip, suspect this happens when inverter "zero's"

Inverter is set to 0% export

 

Hi Peter

Welcome

I had the same trouble with a BEC23. 

Two solutions 

1.  Get your municipality to ask Conlog to supply you with a token to switch the line reversal off. There is no advantage to you as I think the meter is not bi-directional and you would have to pay to export. Good luck with getting your local municipality to OK that. I have been trying for 6 months.
2. Have a constant 150W or so load and feed the wire supplying it the wrong way through the CT on the municipal supply side and this will trick the grid limiter that you import of grid power is 150W less than it really is and then your meter will not trip.

Other than this problem I think Goodwes are great inverters.

Thank you Chris

The inverter came with the EZ meter,no clamp ct. This means I will connect the 150w load on the municipal supply side of the EZ meter? This way the conlog will see a constant load?

1 hour ago, Peter Woest said:

Thank you Chris

The inverter came with the EZ meter,no clamp ct. This means I will connect the 150w load on the municipal supply side of the EZ meter? This way the conlog will see a constant load?

Jip

maybe we can compile and publish in a thread a list of tripping and non tripping Prepaid meters. I was lucky, my

Landis + Gyr CB Wired CIU 20-00582

is not tripping.

It's a problem if your municipality only use Conlog.

i have heard of other whose Landis does cause tripping.

Talk about tripping. This morning my RCD tripped and would not reset. I eventually discovered that we (the electrician and me... but mostly him, I just failed to notice) wired the neutral side of the Carlo Gavazzi modbus meter to the neutral bar (post RCD) while the live side was feeding from before the RCD. It worked fine for two whole years...

I scratched my head this morning trying to figure out why there is only 80V on the input of the meter. Well... that is what the voltage divider between the CG and the coil inside the RCD got me... :-D

:-)

On 2018/06/04 at 10:38 PM, Chris Hobson said:

Jip

Day 2 without any conlog trips, and a 160 watt lamp lighting up the garage during daytime..feels like a waste but it seems do do the trick. Thanx for your help

You can try reduce it to 100W and maybe even 50W. I was reversing the power through the CT and found I needed about 150W. 

I'm really hoping the LazyWeb* will build my contraption at some point. It's essentially a current transformer wired to the midpoint of a voltage divider with an AC  signal feeding both. The thinking is that when current is in phase with the voltage, the two signals are additive and the absolute value at the output of the CT is always higher than at the divider midpoint, and conversely lower when it is going the other way. Add a cap to integrate it, and you should have a signal that can feed a small MCU, and then you can PWM according to the magnitude. Hand wave hand wave... easy.

You could probably be even lazier and just use the arduino code from the open energy monitor. See this for a discussion, plus the following maths section. IE, an emontx with some custom firmware and maybe a bit of hacking to interface with the PWM output could likely do this for you.

The dream is basically a 100W lamp that lights up just bright enough to absorb the grid feedback.

* LazyWeb. Normally a term meaning you're too lazy to do your own research and you're leaving it for others. Here intended to mean I don't have time to do it, but I wish someone would.

Something I might just do - I have a Goodwe nearby.

https://learn.openenergymonitor.org/pv-diversion/introduction/choosing-an-energy-diverter.md

 

18 minutes ago, Chris Hobson said:

https://learn.openenergymonitor.org/pv-diversion/introduction/choosing-an-energy-diverter.md

 

Oh goodie! Wonderful! There you go people... the answer. Using a triac was exactly what I had in mind: It would literally operate like a light dimmer.

10 minutes ago, plonkster said:

operate like a light dimmer

Just something about that, to avoid noise you want to use an opto-triac that has zero-point crossing detection. The MOC3043M used in the example driver is such a device. Caveat though, ideally you want to switch on zero current rather than zero voltage, but for a resitive load that would be the same thing. So this should work rather neatly.

I have to use fans in my garage. The inverter goes above 50C at times. In winter not so much.

One fan under the GTI and one above extracting. I am assuming the fans can also be linked to a thermal device to turn them on when required as the temperature of the inverter and environment is related to the amount of sunlight.

At least when the council installs the prepaid meter, the load would also be serving a purpose other than drawing energy.

https://learn.openenergymonitor.org/electricity-monitoring/ct-sensors/how-to-build-an-arduino-energy-monitor-measuring-current-only

@plonkster's  voltage divider is there  and  a word of warning do not connect a current transformer open circuit it always needs a load even it is just an built in or external burden resistor.

 

5 minutes ago, Chris Hobson said:

word of warning do not connect a current transformer open circuit it always needs a load

Of course :-)

I always knew you could detect current using a CT. I was unaware until doing a Goodwe install that the CT could give direction of AC current flow. Now I see that the maths behind it is simple.

2 hours ago, Chris Hobson said:

CT could give direction of AC current flow

On its own it can't do it, but with a voltage signal you can see if the current is in phase with the voltage or not. It gets even more interesting, even a normal household have tiny feedback periods wherever there are inductive loads, what you're interested in is the sum of the products over time... that tells you which way it is going. With modern non-linear loads it gets especially ugly.

1 hour ago, plonkster said:

On its own it can't do it, but with a voltage signal you can see if the current is in phase with the voltage or not. It gets even more interesting, even a normal household have tiny feedback periods wherever there are inductive loads, what you're interested in is the sum of the products over time... that tells you which way it is going. With modern non-linear loads it gets especially ugly.

Oh dear perhaps I don't understand what I thought I understood. How does EzMeter and Solar Log do it then since they don't measure voltage? -Or do they and I am not taking it into account?

53 minutes ago, Chris Hobson said:

How does EzMeter and Solar Log do it then since they don't measure voltage?

They probably measure voltage. Usually these devices have to be powered somehow, if they are powered from the AC side, they can take a measurement using their own power connection. Even if they use a low voltage transformer, they can sometimes derive it from there.

From Ez-Meter manual:

For Solar-Log (I don't know these products) it seems the product is a monitoring device and the actual readings are done by external accessories. So you would likely need to use a capable modbus meter or something.

 

On 2018/06/07 at 10:20 AM, plonkster said:

Just something about that, to avoid noise you want to use an opto-triac that has zero-point crossing detection. The MOC3043M used in the example driver is such a device. Caveat though, ideally you want to switch on zero current rather than zero voltage, but for a resitive load that would be the same thing. So this should work rather neatly.

Any reason not to use a SSR?

Edit: OK OK cost is definitely one good reason not to use SSR.

4 hours ago, Chris Hobson said:

Any reason not to use a SSR?

That's essentially what many SSRs are. Opto-Triac with another larger Triac doing the real switching. You can obviously only switch AC with such an arrangement, because a Triac is two back-to-back Thyristors, and a thyristor only stops conducting when the current passes through zero.

So you could indeed use an SSR.

Received the first of my goodies and have started prototyping.

On 2018/07/02 at 4:04 PM, Chris Hobson said:

Received the first of my goodies and have started prototyping.

I am very interested in your prototype. How well did it work?