Energy Matters Forums

[Gordon-Loomberah]

I really need to know whats coming out of the battery's not through the inverter for true total consumption.

You need an external shunt before the inverter, which is how I do it, and log with a Graphtec data logger.
I know from previous monitoring that the available AC is only 65-70% of the DC power I put into the batteries.
That's made up of ~85% inverter (Latronics 3024 and 4024 are similar) efficiency, including the always on power consumption, and ~80-85% PV+wind to battery charging efficiency, including float and EQ time, which don't actually add anything to the stored capacity.
I have a thread that discusses one of my tests here: solar-wind-gear/topic1936.html

[Cherokee Solar]

Hi offgridQLD,

I'm assuming that as you have an inverter - charger from Selectronics, you don't have a separate regulator?

If you did, you could include a shunt inline on one of the wires between the battery and the inverter (positive or negative - although I've read somewhere that it should be on the negative wire). A shunt, just in case you are unaware, is a block of metal sitting inline on either the positive or negative wires. The block of metal is connected to your regulator by a further 2 smaller wires attached to each end of the block of metal and these wires then hook up to a device that measures the flow of current across the block of metal.

It's also possible that your inverter charger allows you to hook up an external shunt device?

On the other hand, you could just email the technical support people at Selectronics with your query and they should be able to assist you.

It's good to know the daily current (Ah - amp hours) going into and out of your batteries so that you can keep an eye on what you are generating and using.

Hope this helps.

Chris

[offgridQLD]

Hi offgridQLD,

I'm assuming that as you have an inverter - charger from Selectronics, you don't have a separate regulator?

This is something that baffled me at first. Yes the selectronics Ps1 is a inverter charger but in my system they have installed two Plasmatronics PL-40 Regulators.

Basically the selectrinics ps1 is a ac-dc charger & inverter but still needs a regulator when recieving power from the PV. I think It is tied in with the two PLA 40's. Although each PLA 40 has its own LCD screen and I think the data is read by the selectronics ps1 as well. I need to spend some time with the system to see what I can call up.There is one 100amp 50 mv internal shunt and the option for a external shunt with the ps1 but have to look into what has been allocated what.

Basically they have the two PL-40's doing all the PV charging and the slelctronics only becomes AC - DC charger when the generator is running and feeding into it .It Complicates things with three devices that all have a ton of features inputs and outputs.

PS, I have been using shunts on several of my electric recumbent Bike projects for some time . I have a few nice little units called cycle analyst's that can log AH in - out max volt - min volt - Regen, among many other things and can be calibrated to a larger external shunt if need be.

I will fiddle around this weekend and see what i come up with .

kurt

[Cherokee Solar]

Hi offgridQLD,

Hey! I use a Plasmatronics PL60 and I reckon it's a good bit of kit, although the general consensus here is that an MPPT regulator is better.

As a general note, if you are running two Plasmatronics regulators, you may need to incorporate a PLA alarm unit so that the two regulators sync up the charging of the batteries correctly. You may already have one of these, but I couldn't see it on the photo. I've only just learned about these myself from Gordon here on this forum as I have to add an additional PL20 regulator to my existing system to incorporate a few extra panels. Apparently two regulators on a single battery bank can be a bit of a problem - unless one runs as a master and the other is a slave unit which is what the PLA alarm unit does. Other people may be able to explain why this is the case. My understanding is that if you don't run the PLA alarm unit, there is a chance that one of the regulators may be stuck in Boost mode which has the potential of damaging your batteries. I could very well be wrong on this.

To hook up a shunt to the Plasmatronics regulators you also need a PLS2 external shunt adaptor + a 200A shunt - which you can see on ebay. Your inverter maxes out at 12,000w / 48v = 250A - although it would be rare to be drawing that much current!

The ebike project sounds like a great project, I'd love to hear about it.

Regards

Chris

[karlajensen]

I use a Plasmatronics PL60 and I reckon it's a good bit of kit, although the general consensus here is that an MPPT regulator is better

he he, many hardly come close to the reliability of the PL60 and now the price difference can be simply made up in panels.

Aside from that in warmer climates, hardly makes much difference as the batt voltage and string voltages are then getting very much close

[offgridQLD]

As a general note, if you are running two Plasmatronics regulators, you may need to incorporate a PLA alarm unit so that the two regulators sync up the charging of the batteries correctly. You may already have one of these, but I couldn't see it on the photo.
Chris

Thanks for that info Cherokee Solar. I was try to work out what A PLA was as it's listed in the components list in the handover manual so i guess I have one.

It must be there some where but I cant see it perhaps its tucked in behind a panel. I take it it looks like this.


My components list


I will start a new thread regarding my electric bikes. I have already hijacked this one as it is...Back on track ..power hungry inverter standby loads.

kurt