Outback Generator sync option.

nobody928

I have read alot of posts about how outback charge controllers are able to pick up loads with generators.

My question is how do charge controllers work in sync with generators? Can a charge controler turn on a generator automatically if it senses the battery bank is too low on voltage?
Can someone please walk me through how this process works in regardes to running a generator?
What if a generator has a pull cord? How can a charge controller make it start automatically?

Thank you guys for all your time.

Cariboocoot

Re: Outback Generator sync option.

No. Not the charge controllers, the inverters. Charge controllers have no connection to generators at all.

The inverters can be connected to some generators to automatically start them based on a number of criteria, including battery Voltage level. But the generator has to be compatible with this automatic start and it can take some doing to connect the two. Automatic choke and electric start is needed; you can not autostart a pull-cord generator.

You could get the inverter to warn you if the battery Voltage is low and the generator needs starting.

BB.

Re: Outback Generator sync option.

There are some inverter-chargers these days that can also work with the generator in "generator support mode"...

These new-fangled devices are getting very complex to explain their operation in a couple sentences.

An inverter-charger with generator support--Generator running (say 10 amps @ 120 VAC maximum power or 1,200 watts) and a 4 kWH inverter-charger.

Generator running, and no loads, Inverter takes 100% of needed power from generator and charges battery bank.

Generator running, and <1,200 watts of AC loads, inverter-charger reduces charging current to battery bank so that AC in does not exceed 10 amps. Generator powers AC loads.

Generator running, and >1,200 watts of AC loads, Generator supplies 1,200 Watts and Inverter-Charger takes some power from battery bank and "assists" loads by supplying any power needed >1,200 watts--Up to the limits of the Inverter-Charger's AC output ratings.

So--The inverter-charger in generator support mode can make the generator look larger to the AC loads, and yet allow you to run a smaller/more fuel efficient generator (on average).

-Bill

NorthGuy

Re: Outback Generator sync option.

nobody928 wrote: »

Can a charge controler turn on a generator automatically if it senses the battery bank is too low on voltage?

Yes, generators can be started automatically, but they need to have an electric start installed.

In the simplest form, generator starts when battery voltage is low, but this is hardly the best method. Batteries usually discharge during the night, so you would expect the lowest voltage in the morning, before sunrise. You wake up, start your coffimaker, the voltage decreases a bit, goes below the critical lebel, and generator starts. Then you get a good sunny day that would recharge your batteries with solar anyway. You have just wasted the fuel and run the generator for nothing.

Therefore, more sophisticated devices could be used to schedule generator runs more efficiently thereby decresing fuel consumption and prolonging generator life.

Other people believe that they know better when to run their generators than a computer could ever do, so they decide to run the generator manually. But this requires constant involvement.

vtmaps

Re: Outback Generator sync option.

NorthGuy wrote: »

Other people believe that they know better when to run their generators than a computer could ever do, so they decide to run the generator manually. But this requires constant involvement.

All off-grid systems, even with automatic gen start (AGS), require constant involvement. I think AGS is a bad thing if it leads the homeowner to be less vigilant. If you have AGS you need to be aware of how often the generator is coming on, how long it's on for, and whether it makes sense that its on. When things go wrong (sooner or later), if your system is on autopilot the crash will be worse.

--vtMaps

NorthGuy

Re: Outback Generator sync option.

vtmaps wrote: »

All off-grid systems, even with automatic gen start (AGS), require constant involvement. I think AGS is a bad thing if it leads the homeowner to be less vigilant. If you have AGS you need to be aware of how often the generator is coming on, how long it's on for, and whether it makes sense that its on. When things go wrong (sooner or later), if your system is on autopilot the crash will be worse.

You design a system, set it up, automate it to run as you wish and you forget it (except for routine maintenance). Good automated system will start generator when needed, will not start it when not needed, and will not require any attention. It can also tell you when to check water in the batteries, when to add fuel to generator, or when to change oil. If something goes wrong, such as battery capacity got a bit lower, it'll let you know immediately, so that you can react in time. No need for constant involvement.

vtmaps

Re: Outback Generator sync option.

NorthGuy wrote: »

You design a system, set it up, automate it to run as you wish and you forget it (except for routine maintenance).
<snip>
No need for constant involvement.

OK, I agree that with enough sensors and monitors to alert you, you don't need to be constantly involved (sort of like driving a car with a dashboard full of idiot lights and beepers). But for most off-grid systems it is important that someone pay attention to the numbers every day... do the current, voltage, and battery monitor SOC make sense? (sort of like driving a car with a dashboard full of meters).

Most folks with AGS need to be even more involved with their systems because they don't have all the monitoring and control options that you have. Would they know if their generator is starting up every hour for 10 minutes at a time while they are asleep or not home? Some folks don't notice anything wrong until the lights go out.

NorthGuy, even if you don't need to be constantly involved with your system, I suspect that you are.
(you may take that as a compliment).

--vtMaps

Blackcherry04

Re: Outback Generator sync option.

Automation always works great, till it doesn't. It's always the gremlins that you can't predict that gets it. Be it a creature of some kind , a voltage spike, faulty sensor, bad cell in a battery, smashed cricket in a relay or runaway equipment. You can add fail safes, but pretty soon you end up with them piled up 3 deep on top of each other and there is always a weak link somewhere.

I think North Guy has a super monitoring system and automation, hope it works great for him.

I used a AGS until I got a call from my Wife at 3:00 in the morning, I am out of town, said the generator had started ( not expected ) when I got back in town, the first thing is the starter is black, I look and one post is melted off the positive terminal on the battery. A bad starter Relay that Kohler had mounted upside down got moister in it and rusted the return spring and allowed the contact bar to drop and start cranking the generator until the post melted off. Gremlins. The generator never started, it was just turning over on the starter. wonder the whole thing didn't blow up, $600 I was back in business. Of course this didn't have anything to do with the AGS, but I decided the risk wasn't worth the cost and I put a disconnect on the battery to eliminate the chance of it happening again.
.

Cariboocoot

Re: Outback Generator sync option.

I'm not a big fan of auto start either, for just the reason Blackcherry mentioned. More stuff = more stuff that can go wrong.

NorthGuy

Re: Outback Generator sync option.

Cariboocoot wrote: »

I'm not a big fan of auto start either, for just the reason Blackcherry mentioned. More stuff = more stuff that can go wrong.

Then, obviously, you start and stop your new water pump manually, because the pressure regulator can go wrong, don't you?

NorthGuy

Re: Outback Generator sync option.

vtmaps wrote: »

NorthGuy, even if you don't need to be constantly involved with your system, I suspect that you are.
(you may take that as a compliment).

Guilty. But I have an excuse. That might be because I've got freaky batteries that need extraordinary handling, and I still confused about them. This shouldn't happen to an experience system designer.

I think it is mostly a personal preference. If someone likes doing something, there's no reason to automate the stuff. But if routine tasks are totally dreadful, it is good to get rid of them.

BB.

Re: Outback Generator sync option.

Automatic sump pump float switch failed (free floating switch jammed in sump). Professionally wired alarm water sensor failed to alert (does anyone take a bucket and test the flooding sensor?). Noticed sort of humid air from furnace in winter. Near the end, even heard a strange "sloshing sound" when furnace ran. Doh~!

Sump is under home and a pain to even see if there was water in the pit.

$5,000 later, new furnance, new sump pump with dual caged floats and battery powered alarm. Second battery powered water sensor I still have yet to install (pain to get into sump/furnace area).

All the evidence was there--I failed to check.

-Bill

Blackcherry04

Re: Outback Generator sync option.

North, I see where you are coming from, anything can go wrong. In my case I would have known that the Generator did not start, because I understand the system and know the difference in a engine running and cranking. I would have known there was a failure, In this case my wife didn't know the difference. I think that what VT was saying anything on autopilot is subject to issues and without knowledgeable invention gives the illusion that it will work without them doing anything, as we all know in a RE system, thats not a good thing.

Cariboocoot

Re: Outback Generator sync option.

NorthGuy wrote: »

Then, obviously, you start and stop your new water pump manually, because the pressure regulator can go wrong, don't you?

Not at all comparable.

You might as well say "use a bucket from the well because the pump could fail". It could, and has. You notice when you don't get any water after the pressure in the tank runs out.

Now, what are the consequences of relying on automatic generator start and having it fail?

BTW, I do start/stop my water pump manually at the cabin. But not because I expect the pressure switch to fail; I just don't want it coming on when the power isn't up to handling it.

NorthGuy

Re: Outback Generator sync option.

Cariboocoot wrote: »

Now, what are the consequences of relying on automatic generator start and having it fail?

Here's my take:

Manual

You constantly need to monitor your battery voltage, SoC, other things and decide when to run a generator. You do it very well, but once you forgot because you were doing very urgent project on the computer, the inverter cut off, the computer has died and your project was ruined. Other time you went to your firend and it was a blizzard, you couldn't come back to start the generator and your battery bank died. After five years of doing it manually you came to start the generator and it didn't start, and here's the reward for five years of monitoring - you know that the generator doesn't start right away.

Automatic

The generator comes up by itself when needed. First, you pay a lot of attention on when it stats and how. Then you stop paying attention to it. You hear your generator running sometimes, but after a while you even stop noticing it. You spent three weeks in a hospital, but because of the automatic start there were no problems. Then, in five years, you sit home, watch TV and you receive a text message on your phone, which says "You generator doesn't start". You get dressed and go to your generator to see what's wrong. And you say to yourself: "If only did I do all the generator starts manually for these five years, I could get to my generator whole two minutes earlier than I did now."

Cariboocoot

Re: Outback Generator sync option.

Here's my take:

Design system so generator is not a mandatory piece of equipment. Generators lacking fuel or oil don't work anyway.

Look at sky in morning. If it's not nice, Bulk up with gen. Only takes an hour or two at most.

90% of time generator is not used.

Why do you think I keep posting "you need more panels for those batteries"?

NorthGuy

Re: Outback Generator sync option.

Blackcherry04 wrote: »

North, I see where you are coming from, anything can go wrong. In my case I would have known that the Generator did not start, because I understand the system and know the difference in a engine running and cranking. I would have known there was a failure, In this case my wife didn't know the difference. I think that what VT was saying anything on autopilot is subject to issues and without knowledgeable invention gives the illusion that it will work without them doing anything, as we all know in a RE system, thats not a good thing.

Everything can fail. It's very hard to predict what fails, and it is absolutely impossible to protect against all failures.

Manual start can fail too. When I was reading instruction for Champion, they go into great details explaining how the pull cord can pull back with such a great speed and force that you cannot react and let it go, so it just pulls your arm out of the socket. After you read it, you start wandering whether it's worth pulling it or not

NorthGuy

Re: Outback Generator sync option.

Cariboocoot wrote: »

Why do you think I keep posting "you need more panels for those batteries"?

That I completely agree. I wish I had so much panels that I could get by without a generator, but that's not going to happen

stephendv

Re: Outback Generator sync option.

I'm with Northguy (brilliant project btw) on this.

Automation combined with data logging and notification has saved me hours of headaches. First automation project was way back when we just had a generator and water pump and needed to irrigate the olive trees every day, while we were living 12km from the land. Simple arduino + SMS module, and I could start and stop the gen using SMS. It would notify me of failed starts, and it would notify me if it detected current after the gen was supposed to stop (failed stop). Worked 100% for 6 months.

Right now with a little raspberry pi computer + mango automation software the well pump comes on automatically depending on the battery soc and the weather forecast. The comms link between the computer and pump is far from bulletproof: first a wifi link to land at a linux server which switches a Ciseco RF module, which transmits the "on" command to the well pump over 200m away. So that's 3 devices, 2 wifi access points and the Ciseco modules; lots of points of failure.
I get an email when the command to switch the pump is sent and I can check the inverter logs from the comfort of the living room to be sure that the well pump actually came on. It's every easy to get a quick graph of the last week's inverter output, and the 2kW well pump for 1 hour/day is easily visible.

Automation on it's own is quite useful. Automation + alerting more so. And all of that + monitoring and logging from anywhere with an internet connection = peace of mind.

Cariboocoot

Re: Outback Generator sync option.

It must be nice to be rich.

stephendv

Re: Outback Generator sync option.

Cariboocoot wrote: »

It must be nice to be rich.

Ouch. rPI computer cost 40 Euro, Ciseco modules 20 Euro each, so less than 100 Euros for a full automation and monitoring system. Don't have to be that rich

NorthGuy

Re: Outback Generator sync option.

Cariboocoot wrote: »

It must be nice to be rich.

It has probably saved lots of money on gas necessary to drive back and forth 12km (and I think the gas in Spain is about twice the price it is in Canada).

That's what rich people do. They save money

Cariboocoot

Re: Outback Generator sync option.

Just leave out the extra cost of the auto-start generator and connector and ignore having to up-size the system to run everything 24/7, eh?

Let's see; if I were to try this it would be "only" a couple hundred dollars for the monitoring equipment, plus a couple thousand for the auto-start gen, and a few thousand more to double the system size and keep the satellite connection going all the time. Ironically it would then be a much more complicated system far likely to fail. But at least I get a notice that it had. Unless it was the monitoring system that failed. Or the power went out and the Internet connection was down then I wouldn't get any notice. Of course I could spend even more money and make a redundant power system to power the notification system unless something went wrong with that too in which case ....

I think I'll skip the OCD and stick to systems that are simple and keep working even though someone isn't watching them every minute, whether up close or at a distance.

You guys are the reason why I keep having to empty my PM inbox.

NorthGuy

Re: Outback Generator sync option.

Cariboocoot wrote: »

I ... stick to systems that are simple and keep working even though someone isn't watching them every minute, whether up close or at a distance.

Right. Me to.

There are manual system, which you need to constantly watch and maintain.

And, there are automated systems, which work by themselves.

If your system doesn't require watching, it is automated, whether it is simple or not.

Cariboocoot wrote: »

You guys are the reason why I keep having to empty my PM inbox.

:

stephendv

Re: Outback Generator sync option.

Cariboocoot wrote: »

plus a couple thousand for the auto-start gen

It's cheating if you include the price of the WHOLE gen, you just need the auto-start kit. My gen came with electric start, but not auto. Autostart was done with a $60 DeepSea generator control unit, wired into the existing electric start system.

Cariboocoot wrote: »

and a few thousand more to double the system size and keep the satellite connection going all the time.

rPi = 5W
2 x wifi APs (in my case) = 10W
So that's 15W x 24h = 360Wh.

To make that up year round on solar panels = 120W panel = $120

Cariboocoot wrote: »

Ironically it would then be a much more complicated system far likely to fail. But at least I get a notice that it had. Unless it was the monitoring system that failed. Or the power went out and the Internet connection was down then I wouldn't get any notice.

It's not anymore complicated. It's the same system as a manual, except that it _can_ autostart and provides monitoring/notification/fancy stuff IN ADDITION. If all the automation fails, then you're just back to having a manual system.

Cariboocoot wrote: »

I think I'll skip the OCD and stick to systems that are simple and keep working even though someone isn't watching them every minute, whether up close or at a distance.

That's exactly what the automation is designed to do: manage the system so that you don't have to And since it's automated it can do stuff that you don't want to do. E.g. if you had optional electric water heating or space heating, then the automation system can decide whether there's enough sun to turn it on or off, every hour, or every 15 minutes. That's not something a person is likely to want to do.

Machines for machine work

mtdoc

Re: Outback Generator sync option.

I think it was Robin or Bob from Midnite solar who made the comment that they were not a fan of generator auto-start systems because they did not think internal combustion engines should be run unattended. I feel the same..

One of my neighbors have a whole home generator backup that starts and runs automatically when the grid is out. They have a second home and are often gone for days with that thing running. Makes me nervous as hell......