Hey all - I have a bit of equipment which I want to trickle charge but only when the engine running (not just accessory power).Don't want to rely on voltage level alone since there'll be multiple loads so voltage may vary. Short of tapping the alternator line or reading OBD, what can I do to make sure the engine's running before starting charging! Cheers
skin1235,
Feb 19, 7:12am
the regulator already does this your bit of equip would be a battery, suggest a lead to the existing battery with a diode , will only accept charge once voltage is above the small battery's, will also draw from the main battery if load exceeds charge in
greateft,
Feb 19, 7:32am
Ah, well thats what I'd like to avoid - running the main battery flat because its being drawn on without the engine going. If I go on voltage level alone, the equipment will not be able to tell whether it's drawing on just the battery, or the alternator in conjunction with other loads. I'd like it to cut its charging exactly when the engine's switched off, so it doesn't draw from the battery alone at any time.
pup2,
Feb 19, 7:43am
Use a Voltage Sensitive Relay switched by the charging voltage
granada,
Feb 19, 8:05am
Or connect it through a relay that is operated byan oil pressure switch
pup2,
Feb 19, 8:07am
Now that is a great idea. Way cheaper as well
greateft,
Feb 19, 8:40am
Now that sounds like a winner! Cheers all
aredwood,
Feb 19, 9:39am
Another method. Connect into the wire that goes between the alternator and the battery warning light. When the alternator is working fine there is 12V on this wire. If the alternator fails the voltage drops to about 2V. This means that your load will be disconected if the alternator breaks and it also won't be connected while the engine is cranking. Although I like the oil pressure method due to its simplicity.
aredwood,
Feb 19, 9:42am
Yet another method. If the engine uses an electric fuel pump the ECU should be switching its control relay. To switch the fuel pump off automaticly if the engine stops for any reason. You would be able to use the fuel pump power feed to switch a relay.
Since the public registrations are closed, you must have an invite from a current member to be able to register and post in this thread.
Have an account? Login here.