Is there a ready hot wire for bottle heater on our cars?

[North Cali Autocrosser]

<blockquote>quote:</font><hr>Originally posted by OneQuickV6:



I gotta ask what you mean here!? Why would you run almost anything straight to the battery so it DOES have more current flowing in it? 500A can't be good for a heater. Use a relay to simmer it down some, or use a small current source like your stereo's power wire.<hr></blockquote>

I should have made myself clear when I said hook it directly to the battery. The continuous supply should be hooked directly but it runs to a relay that is supplied with the heater. Sorry for the mass confusion. :D

[North Cali Autocrosser]

One thing to add, whatever you hook to a battery it will only draw the amount of amps it needs, you won't melt anything by hooking it directly to the battery. If you put a $10 voltmeter from AutoZone on a 1000amp battery does it explode in your hand? No. The relay is a safe way to trigger the heater on and off through the switch and the thermostat.

[OneQuickV6]

<blockquote>quote:</font><hr>Originally posted by North Cali Autocrosser:
One thing to add, whatever you hook to a battery it will only draw the amount of amps it needs, you won't melt anything by hooking it directly to the battery. If you put a $10 voltmeter from AutoZone on a 1000amp battery does it explode in your hand? No. The relay is a safe way to trigger the heater on and off through the switch and the thermostat.<hr></blockquote>


Have you ever tried to wire one of these components up straight to the battery without a relay? A friend of mine went to wire his solonoids a week or so ago without a relay, and it melted his wires within moments of activating the switch. And yes, it does put more current than needed thru the lines, not just what is needed. The resistance in the lines and what's at the other end of the circuit is what decides how much current will flow thru your wires...more resistance, less current. It takes the path of least resistance. So IMO and in every other EE major's opinion, a relay is not the safest way to do this, IT'S THE ONLY WAY! I'll get off my soap box now.

[Phoenix]

If the wires melted then he was using to small of a wire, the solenoids were trying to draw more amps than the wires could handle or he used wire with to few strands running through it.

[OneQuickV6]

<blockquote>quote:</font><hr>Originally posted by Phoenix:
If the wires melted then he was using to small of a wire, the solenoids were trying to draw more amps than the wires could handle or he used wire with to few strands running through it.<hr></blockquote>

No, he was using 10 gauge, nice speaker wire. Between 10 gauge and 18 here isn't a HUGE difference, both will melt nearly instantly if hooked straight to the battery, try it. Bottom line, ALWAYS either use a relay to minimize the current thru your electrical stuff, or use an already small current source like your stereo.

[Phoenix]

I have tried it and it's fine, do whatever floats your boat.

[12secondv6]

<blockquote>quote:</font><hr>Originally posted by OneQuickV6:

A friend of mine went to wire his solonoids a week or so ago without a relay, and it melted his wires within moments of activating the switch. <hr></blockquote>

Yup, done that before, whoops [img]smile.gif[/img]