Simple generator start

[BruceM]

Automotive starter relays are out there and not that expensive. Or use a solid state DC relay, or make one with a MOSFET.  

About drawing from a 12V battery which is part of a bigger series string...if the batteries are each charged separately with a 12V charger,  sure, that's fine.

But if two or more 12V batteries are charged in series on a single  charger, and you imbalance the batteries by discharging one more than another, the batteries will be ruined fairly soon.

[dubbleUJay]

I have 16 Trojan L16H batteries so the amp drain should be not noticed I imagine.

I should have read the thread better, sorry. You have a 12V starter, I was thinking 24V, but it doesn't matter. 8x Trojan's in series for 48V and 2 of these banks if you have 16 of them?
If that's correct, you want to use 2 of the 8 in 1 of the banks to start the engine so you'll be using a 1/4 of the battery bank for starting.
I dont know your starter, but say it draws 40A for those couple of seconds to start, surely there would be a voltage drop over those 2 batteries for that few seconds and the Xantrex should notice it unless it has some type of delay in the monitoring of the bank? It might try to switch on the charger or solar or what ever to try and charge the bank in that short time period. That's what I was trying to explain.

The inverters are 2 Xantrex SW+ 5548's, the positive and negatives are hooked into the inverter through a DC breaker, the inverters are grounded and the AC is grounded at the house.

Can you check with a meter if there is a connection between your batter negative and the AC ground wire? Or the metal chassis of the inverter for that matter.

I have a car battery hooked to a 10A manual charger which is probably too much juice, I run the SR2 about 5 hours a day. Every couple of days I use the charger to charge up other batteries instead. I'll keep an eye out for a better charger that will do 2A auto and just keep it plugged into the generator output, that should work.

This should be fine for a controller battery, I thought you might need two for 24V starter, but this makes it even easier!

I still don't know how to set up the relay to start it remotely though, I have a board that will trigger a standard 12V car relay and I have a handful of relays but the switch looks like a simple contact switch so handles a ton of amps which I'm sure the car relays won't handle and high amperage relays are $?

I've got a SR2 (LR2)?? manual somewhere that shows electrical connections of the engine when used in a auto-start generator application. I'll see if I can find it.
The thing is you need to know when the engine is running so that the starter can be automatically disengaged.
The manual showed some switches and solenoid purposely made for the application. Does your engine have something like that on it?
FYI the old Mini's and some Ford Escort's had the starting solenoid separate from the starter motor, mounted on the wall inside the engine compartment, those would definitely take the current.

[Jedon]

I'm kind of liking the idea of keeping my battery bank out of the equation, doesn't seem worth the risk or hassle.
This work? http://cgi.ebay.com/ebaymotors/NEW-STARTER-RELAY-SOLENOID-SWITCH-JOHN-DEERE-KOHLER_W0QQcmdZViewItemQQhashZitem4ce96b904fQQitemZ330333655119QQptZMotorsQ5fATVQ5fPartsQ5fAccessories#ht_1666wt_939

Does your engine have something like that on it?

No, just one big metal push and hold button.

Can you check with a meter if there is a connection between your batter negative and the AC ground wire? Or the metal chassis of the inverter for that matter.

The inverter and batteries etc are in a shed 180ft from the house where the AC is grounded. 3 wires go from the shed to the house, the 2 hots and a neutral. The breaker panel at the house is grounded into the foundation, forget what they call it, big copper wire wrapped around the rebar. The inverter chassis is grounded at the shed to a 1/4" copper rod sunk a few feet into the ground. The inverter is not grounded.

It might try to switch on the charger or solar or what ever to try and charge the bank in that short time period.

The solar panels are hooked directly to the battery bank, not even a charge controller involved ( yet ). The panels are 65 and 69V but the battery bank brings down the voltage, not super efficient but I don't even have the panels mounted yet, they are just leaning against the shed so far, I had to go clear the snow off of them  :-D

[dubbleUJay]

That solenoid on eB@y will work, it the same type of thing I was talking about for the Mini&Fords. It effectively do the job of what your start button is doing now, but if your down by the house were you want to start it from, how would you know when to release it when the engine fires? That's what I mean with some type of sensing contact to disengage the starter.

The Earth Pegs have different names, here we call them Earth or Ground Stakes, anyway, they all do the same job
With your description I still don't know if your battery negative is grounded, like in a car to the body.

By switching on the solar and stuff by the inverter, I meant also your build in battery charger of the inverter if it has one?
Its just better and simpler to have a separate battery IMHO and I think you see that now.
I'll look for the manual quickly and post the diagram I spoke about earlier (if your still online)

[dubbleUJay]

Jedon, here are two pictures that I found in two of the manuals, the one's from SRM engine, but its just the marine version.
I could not find pictures of the actual parts, just the fuel cut-off solenoid.
This is just to get an idea of how Lister did it, you can make most of the things.

[mobile_bob]

i don't know what engine you are using, but
if it has a real oil pump, you can put in a pressure switch and use it to break the circuit to the starter relay

basically you initiate a start, and the engine will crank until the oil pressure comes up, at which time the engine
should be running.

the use of an orifice fitting to restrict the oil flow to the point that it slows the switch cutoff might be needed to
get the engine running before oil pressure is sensed and the circuit is interrupted.

an oil pressure interrupt in the starter circuit is a good thing in any event keeping a fault from engaging the starter
while the engine is running.

there are ford type starter relays that have isolated field coils, unlike the true ford type where one of the small terminals
is for the start circuit and the other is for the energization of the ignition coil, the alternative relay has two small terminals
one is for the start circuit and the other is the ground side of the relay coil,

the ford type finds its ground through the mount bracket.

bob g

[TimSR2]

Starter draw is closer to 200a than 40a. Still negligible to those batteries. They won't mind at all. Rotate out the start pair once a year if you are worried. We are not talking a lot of amp/hrs here. 200amps  for 10 seconds is bugger all to your house battery set.

If you insist on remote start capabilities a remote oil pressure sensor should give you a low tech way to figure out when to take your finger off the start button. Or even an exhaust flapper actuated microswitch, if you can figure out how to weather proof it. 

There's really nothing wrong with just trudging out there to check the oil and flip the decompressors by hand once a day. KISS is king. It's British--- you gotta keep an eye on the oil leaks anyway.

Regards,

Tim

[dubbleUJay]

Just for reference, Lister usually used a micro-switch connected to the governor linkage to sense when the engine is running.

[BruceM]

Right, Tim, with L16s and regular equalization, I'm sure you could get away with that. I didn't check the size of bank Jedon was using.

Many folks are so bad about battery care that it still could make a bad situation worse, and it is technically a bad solution.  (Drawing a load from part of a larger series string which is charged in series.)  What a knowledgeable guy who knows and takes care of his batteries can get away with is another thing.

[Jedon]

The board I am going to use for the remote/auto start can trigger a relay off when it sensor power on another input so I thought I could just hook the AC alternator output to an analog input on the board to sense if it's on?

Just for reference, Lister usually used a micro-switch connected to the governor linkage to sense when the engine is running.

Governor linkage, I don't really see where that would work on an SR2? Unlike the 6/1 I can't see anything moving or changing when the engine is running on the SR2.

If you insist on remote start capabilities a remote oil pressure sensor

Oil pressure would probably be a good sensor to have anyway. One reason I would like a way to auto start it is so that the inverters can start the generator if the batteries get too low, this is not something I would rely on normally, it's for emergency situations. All our communications require power so I would not like the situation where I am gone, my wife gets hurt and the power runs out and there is no way for her to call for help. I tired putting a UPS on the comm equipment but the UPS likes neither the inverter power nor the generator power, I'll have to find the manual and see if I can set the tolerances lower.

Starter draw is closer to 200a than 40a

[BruceM]

Jedon, AC voltage, perhaps with a dropping resistor, to an AC coil relay as a start signal might work, but you'll have to run a test to find out. It might take too long for the AVR to kick in, or some other issue.

It might work, and couldn't get any simpler;  the AC relay could be a normally closed SPST, and when it opens from AC power being present, it could open the power to the starter relay coil.

[Jedon]

TW, there is currently a seller on ebay with some variable reluctance sensors

I'm quite often variably reluctant :-)

for example, let's say your belt breaks or comes off

It's direct drive, no belt but point taken. Plus I may want to adopt something like this for the 6/1 in the future.

AC voltage, perhaps with a dropping resistor, to an AC coil relay as a start signal might work,

The guys who make my board say they have done this before so I guess it would work at least under some circumstances.

[jasoncarter]

Here is the start controller I plan to use on my Perkins 402 project.  I haven't bought it yet because I'm not that far along. 
http://gencontrol.co.uk/index.html

You can order it with custom parameters.
http://gencontrol.co.uk/Generator%20Control%20Module%20Creator%20for%20advanced%20engineers.html

The the price is right too at £60-£70 depending on the model (about $98-$114 currently).  Some options like the battery voltage monitor drive the cost up a bit.

If anyone here has used one of these I'd be interested in their opinion of it.

[BruceM]

Nice find, JasonCarter!

Looking at their specifications, these seem quite capable, and fault conditions are monitored, so it would be a complete engine controller.  The price is right, too.

There are some hitches if being applied to a Lister(oid) CS;

For an oil pressure-less Lister(oid), the oil pressure signal could be faked via Cherry gear tooth sensor (hall effect type with exciting magnet in unit)  on spokes or inductive pickup, and some analog signal manipulation.  Since Jens is going that way, perhaps he'll share his completed circuit when he's done.

Some extra embedded processor control would be need for startup and shutdown, to operate SOM- like decompression/rack closing.  When the start signal is active, the rack would be closed and decompression engaged before cranking, and decompression and rack released at an appropriate speed, so that the controller didn't have to know about it. 

A far better solution would be to get the manufacturer to do some custom code to handle rack/decompression.  The "custom" parameters they offer won't do the job. 

[Jedon]

Jens, what is the voltage range you will be using?