Is there a way to eliminate inverter idle draw?

[Janne]

So are you looking to turn inverter off at a certain time or times or remotely or if there is no load on the inverter.

Sorry I didn’t read you’re question correct the fist time. So the correct reply is: I want the inverter to 1.switch off completely when it’s idle and the batteries are low
2.turn on again when the batteries reach a certain “higher voltage” (the inverter would not have any load on it when step 1and 2 occurs).
My batteriepack is 7x2.65-4.0v 40ah lion + 7s lipo “blocks”~40 ah in parallel. I’m planing to build 7s pack out of my 1000x18650 pre used Panasonic ~1400-2000 mah.
Thanks

 

[Janne]

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/303181391497.
Something like this

Thanks for the suggestion, so I would need to open the inverter and solder on wires from this droc device?

 

[Janne]

Oh, now I understand. You have an existing inverter and an existing ATS that already changes your load to grid, you just need a way to turn the inverter off too, and I'll add on in such a way that won't degrade the inverter over time. Some inverters have a remote on / off button that does the same thing as the button on their panel. The trick is its often a momentary switch to turn the inverter on and off, push/release to turn on, push/release to turn off. My Giandel branded inverter has this and even comes with the remote button. What is the make and model of your inverter? It might have a socket for a remote button already, which would make tapping in a controller to turn it off / on much easier.

If you could buy a new inverter you could get one that has the auto low power mode and it'd be perfect for what you are doing.

I can’t remember the make, it’s Chinese but sold in Sweden = probably better batches and with warranty.. I post two pictures from my setup.
(Ps. I don’t care about voiding the warranty if needed)
Thanks

 

[Russ]

Man just when I think I may be getting close to some comprehension of this stuff I get this thread sprung on me. Always something new or new to worry about.......?

 

[efficientPV]

No smoke there apart from what might come out of the inverter. Removing DC from the inverter wasn't something I thought about, rather turning it off / on via the control circuit. Frequent heavy inrush current would degrade definitely degrade the caps.

It would if you were switching the input power. In an inverter the FET and capacitors are connected all the time. The switch just powers up the control electronics which is about 100ma. My dedicated inverter runs just my fridge and only turn on when needed. I saw someone powering a fridge only on youtube running the inverter on all the time. His drew 2A at idle. He had to have 60% more panels just to run the fridge and bigger battery because he couldn't be bothered to turn it on and off with the temperature control.

 

[Craig]

Thanks for the suggestion, so I would need to open the inverter and solder on wires from this droc device?

Probably but there could be other ways depending in inverter

 

[gnubie]

I can’t remember the make, it’s Chinese but sold in Sweden = probably better batches and with warranty.. I post two pictures from my setup.
(Ps. I don’t care about voiding the warranty if needed)
Thanks

That looks like a standard on / off switch on the front panel. Hopefully not switching the DC input, you never know. No remote power option though but given that it looks like a normal switch the controller posted by Craig earlier may well be able to do the job but would need the inverter opened up to connect wires, and definitely would need to see what that switch is actually doing. It could be soft on / off, but it could be switching the DC input too.

 

[Janne]

That looks like a standard on / off switch on the front panel. Hopefully not switching the DC input, you never know. No remote power option though but given that it looks like a normal switch the controller posted by Craig earlier may well be able to do the job but would need the inverter opened up to connect wires, and definitely would need to see what that switch is actually doing. It could be soft on / off, but it could be switching the DC input too.

Ok, good to know, I’ll be looking out for how the switch is connected inside, when I see the wires I probably can figure out which way it is.
Thanks so very much to you and all others to so helpfull!

 

[Craig]

I would wire it in paralell with built in switch that way you can manually turn it on of voltage switch fails.

 

[Janne]

I would wire it in paralell with built in switch that way you can manually turn it on of voltage switch fails.

Thanks for the tip!

 

[offgriddle]

I've been shutting off my El cheapo off the shelf invertor for six years using it's own toggle switch several a day without any adverse effects.

 

[offgriddle]

PS: I haven't put my multimeter in line with the positive freed to my inverter to see how many amps it draws at idle, but the housing is slightly warm to the touch so I know it's eating watts.

 

[gnubie]

I've been shutting off my El cheapo off the shelf invertor for six years using it's own toggle switch several a day without any adverse effects.

Maybe we've all been over theorising it a bit

 

[offgriddle]

An invertor can completely shut off for zero current draw after an idle period but because they are completely shut off to achieve zero power draw, there is no circuitry "alive" to monitor for any demand for power, therefore, you have to manually turn the inverter back on!

 

[gnubie]

Inverters with that feature usually don't turn off completely. The smarts stay on all the time but draw very little power and periodically wake up the inverter to send a blip to the socket to see if anything actually wants to draw power.

 

[offgriddle]

Yep, the only way to create a state of zero power consumption is to turn a device completely off. Hmm, I wonder how often the smart inverter polls it's AC receptacle to check for demand? Polling is an energy consumptive task in of itself also.

 

[gnubie]

Victron's small inverters do it at 1 minute intervals. Their power consumption in this mode is about 1 watt, so not really worth even thinking about.

 

[offgriddle]

Victron's small inverters do it at 1 minute intervals. Their power consumption in this mode is about 1 watt, so not really worth even thinking about.

One watt is not much at all. Victron, based in the Netherlands, around since 1975, looks like they are a manufacturer of higher quality inverters and battery systems and monitoring.

 

[grizzzman]

Thanks for the tip!

My 2000 watt set up is done this way.(but now i need to test "off idle parasitic amps)

 

[Janne]

Just to check that I got it right, and maybe get some heads up about something regarding..
So have we come to a conclusion (with in between the lines disclaimers) that it’s a probable or possible solution to use a grid/off grid ac/ac auto switch (to sett voltage so no load is on the inverter) combined with the droc (Craig suggested) to minimize idle draw from the inverter? (Grid/off grid switch sett at 23/28 volt off/on, droc set at 22.9/27.9 volt off/on)
{edit}The second sentence should read “have I got to an reasonable conclusion“. I’m so indoctrinated with the Swedish consensus culture, consider it as a Freudian default (hate it btw).