800w inverter in cigarette lighter socket

Here is my situation: . I connected an 800-watt peak power inverter to my cigarette lighter.    When I turn the ignition completely "off", the stereo (and thusly my amplifier) will continue to play for about 90 seconds. . I assume that the 12v+ signal wire on the head unit is getting enough power from the capacitors in the inverter to keep the head unit in an "on" state for the 90 seconds... . I see no way that this can harm my head unit as it would normally be getting the same type of signal, and nothing else runs on that same circuit in my dash. The only other thing that circuit powered was the light-bulb in the ashtray, which was discarded 5 years ago because smoking is not allowed in my car. . The stereo receives power from the fusebox and is only "on" when it receives a signal from the ignition (and/or, in this case, the inverter or capacitors). The amplifier runs directly off the battery and is only in an "on" state when it recieves a 12 volt signal from the stereo. for these reasons, I don't thing there is enough current-draw from the inverter to damage it. My questions are: . Can anyone think of any way that this might damage anything? Inverter included? . If I were to purchase a low-end model of the larger caps like one would connect to the power input of an amplifier and mount that cap SAFELY inside my dash some where in parallel with the stereo circuit, could I theoretically SAFELY keep the stereo "on" for a few minutes after the key is turned off? . Would it be smarter or safer in some way to use one of the several suggestions for using latching relays or relay arrays to do this instead? (possibly just because touching a battery won't hurt you like touching a cap?) A little more about my equipment: (Please don't laugh too hard ;) ) 97 Mazda Protege EX VR3 (Walmart) head unit with SD card-slot and USB port 1000watt "Lightning Audio" (Walmart) amp "Sondpass" (I think)(PepBoys) full-range speaker-box. . I am *NOT* bragging or looking for competition audio or anything else, just telling you what I have and what I could afford when I bought the stuff. The ENTIRE 'system' was less than $300, including installation, which I did myself.

An 800W inverter in a cig socket???!!!! A 150W inverter maybe, but not 800W. 800W is way in excess of 50 Amps; a cig socket handles 15A at most. Please include what voltage your HU is. An inverter is taken to be an AC output and most 12V DC HUs do not like 110V-240V power supplies. You do NOT use capacitors to power amplifiers - you use batteries. I fact on this forum, you will find few that suggest using capacitors for anything to do with sound systems except as noise filters and timing/delay devices.

ditto

I'm sorry I have taken so long to check on this thread. I was expecting email notifications .... I am not RUNNING the HU off the inverter. The HU is a typical aftermarket CD player from walmart as I said in my initial post. The inverter unit is 800watt PEAK and is DESIGNED to be plugged into a lighter socket. Directions on the bottom of the unit say that if you intend to use more than 200 watt, to remove the cigarette lighter cable and attach the included battery clip cable and power the inverter directly from the battery. I may not have been clear in my initial post about the use of capacitors and for that I apologize. The capacitors *ARE* connected to the power inputs of amplifiers, in parallel with the battery power, so that when the amplifier tries to draw more current than the battery can supply at once, the capacitor can assist. I did not intend to imply that the capacitor is the primary source of power for the amplifier. I was thinking about using the relay set-up described elsewhere in The12Volt for "Retaining accessories" until a door is opened but then I realized, if I start the car off the remote starter, it will turn on the accessories and 'set' the relays, but then when I turn off the car (or 12 minutes is up), the relays will remain on indefinitely, since no one will be in the car to open the door..... I need something with a timer What is happening in my case is that the circuitry inside the inverter is storing some power when the ignition is turned on and is releasing it back into the accessory circuit when the ignition is turned off. This power is keeping the HU in the "On" status. The stereo gets all the power it needs from the constant battery wire and only gets switched on and off from the ACC wire from the ignition. I will check my email notification settings and hopefully pay a little more attention to this thread for replies.

The only way of stopping internal caps from holding up an HU line is to insert diodes in the inverter +12V - but that's not practical. You'd be better off disconnecting the inverter +12V (relay) else maybe connecting a resistor to discharge the inverter caps quicker. The inverter's caps should not be very large.

if you read the instructions on the inverter. They are not meant to be plugged in ALL THE TIME. only when in use.

Is anyone going to answer the questions I asked or tell me everything that is wrong with what I said? I KNOW you aren't supposed to leave the inverters plugged in all the time, the sole reason for my post was asking a safer way to get the same effect!

You can leave an inverter on all the time . . . many if not most of them do not have any appreciable idle current, just read the instructions for your model.

Now for the meaty stuff.

You want to run the stereo when the key is off, bully for you. Run the power straight from a primary battery or secondary battery and put a switch and contactor and in line fuses.

When you flip\push\click a switch the relay (contactor) will supply all the juice your fuse will handle and you can listen to the radio until the battery runs down.

What ratiing and parts list do you need? I dunno, it's not my point to explain that here, just supply the proof of concept that you can bypass the ACC and lighter outlet and inverter for your needs.

I know just enough to be dangerous. VERY dangerous.

what I want is for the stereo to remain on for a defined period of time (20 minutes?) or until a door is opened.. I had no intentions at first of having a timer but I realized that there wont be anyone to open the door if I remote-start the car to let it run for 12 minutes, which I do in the winter. I would have to go out to the car and open and close the door every time I remote-start, which would defeat the purpose of remote start. . .