saving batteries on machine

[isabella]

When a certain machine’s engine is off but the ignition is still at the on position, the lights, screens etc. still work. There is nothing wrong with that, the problem is when the lights is left on too long, the batteries gets flat and it takes a lot of effort and time to boost the batteries for starting the machine. I need to think of a way to prevent this from happening. Does someone have an idea? I have included a sketch of how the batteries are currently connected. My thought was to disconnect battery set A and B with contactors, when the machines engine is off (when no excitation signal is picked up) , and when it gets the start signal the contactors close and the one set of batteries boosts the other. Will this work? Please help.

 

[tmd_63]

Unfortunately I can not see the sketch and so can not comment.
There was an article in an old electronics magazine that addressed this issue in an old style mini. They used a second battery with a charging diode and a heavy duty relay connected to the ignition switch and supply. This had the advantage of charging whilst the engine was running but keeping the second battery disconnected until the first supply reduced to a low level on restarting.
I will try and find the relevant magazine article (it was practical electronics or everyday electronics or similar).

 

[bobstay]

The standard way of doing this is to have a chime/buzzer when the lights are on and the door is opened. Perhaps if your machine doesn't have doors, or doesn't have a door switch, you could cause the buzzer/chime to operate if the engine is off and the lights are still on. That way it's harder to forget th turn off the lights.

Alternatively, you could monitor the battery voltage, and switch off the lights when it falls below a certain preset voltage. The lights would almost certainly come back on when the engine is started, because the alternator would raise the bus voltage.

 

[tpetar]

When a certain machine’s engine is off but the ignition is still at the on position, the lights, screens etc. still work. There is nothing wrong with that, the problem is when the lights is left on too long, the batteries gets flat and it takes a lot of effort and time to boost the batteries for starting the machine.

Try to keep all off when engine is off or make that all goes off when contact is in off position.

I need to think of a way to prevent this from happening. Does someone have an idea? I have included a sketch of how the batteries are currently connected. My thought was to disconnect battery set A and B with contactors, when the machines engine is off (when no excitation signal is picked up) , and when it gets the start signal the contactors close and the one set of batteries boosts the other. Will this work? Please help.

Yes this with adequate contacts can do the job, but about what machine we speak ?

I saw some solution with additional isolated single cell in serie with existing six cells. When starting this cell is added to existing six cells and give additional voltage boost, after engine is started additional cell is turned off. When engine running this additional cell is recharged with special voltage regulator for 2,2V. If battery have 100Ah, this additional cell also should have 100Ah.

 

[iop95]

You can cut lights when motor stop or sense driver presence (by a switch in chair) or steering moving (low cost magentic sensor); may add some delay between events and command.

 

[BradtheRad]

Recreational vehicles have to allow running accessories with the engine off. To ensure the engine can be started, separate batteries, steering diodes and relays are often used.

I wonder if there has been a change in vehicle ignition switches over the years. A difference as to how many positions you can turn the key so you can operate accessories when the engine is not running. There is the position one step back from the starting position, that energizes the alternator field coil, which can drain 3 or 4 amps invisibly. I don't know if some cars do or don't prevent unnecessary drain when the engine isn't running.