'85 300SD Electrical question

I have an 1985 300SD Turbo. I just had to replace the alternator and the starter switch - big $. There is an amp wired to the battery and the mechanic disconnected it saying that it was drawing too many amps and was
draining the battery - which he claims ended up burning up the stuff in the charging system (alternator and switch). The wire to the amp is connected to the positive terminal and he claimed it arched (sp?) really bad proving his point. When I tried to reconnect it to the battery it didn't arch at first, but then it actually did pop and crackle really bad. My question, does this arching really mean anything? How can I tell if the amp is drawing down the battery? Could it be that the alternator and the switch was the problem (battery going dead and electrical acting up in car) and I am okay now?
Thanks in advance for your help. Chris
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The amp is for a music system?
There should be no arcing - not even a tiny spark - when this amp is OFF. If there is a current draw when the amp is OFF then something is wrong with it. The amp should also have a fuse between it and the battery.
Read the amp's specifications, specifically how many amps it draws, and install a fuse of that amperage in its power lead. I suspect the amp is shorted but the only way to really know is whether a correctly sized fuse carries the amp's specified load.
Attaching the amp directly to the battery means that anyone can play it anytime the car is unlocked, the ignition key isn't needed to run the amp. Do you want that?
However you arrange the amp's power be sure the connection is clean, fused and tight.
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Maybe not. There's usually a signal wire from the radio/deck that tells the amp to turn on.
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If an amplifier is installed correctly, it will only turn on with the signal from the source unit (as Richard stated). Amplifiers contain a power supply that often contains large capacitors. When an amp has been disconnected for some time, the caps lose their charge. when connecting the power cable, you will get a spark from the current draw of the caps charging. The amp's battery wire should have an inline fuse (within 18" of the battery) that should blow if the power wire becomes directly shorted. Most amps also have on board fuses to protect from over current situations. Most "mechaincs" do not understand how aftermarket electronics affect an electrical system. This also leads them to blame the aftermarket piece for any issue that they can't figure out. To properly discover any current draw issues, you must use ammeter inline with each suspected circuit.
Todd todd snipped-for-privacy@myrealbox.comREMOVE
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