more questions about charging batt w/ tv

[ccarr113]

I'm looking through old posts trying to get the best set-up for charging my battery while towing.  I have gotten a lot of info here like the orange aux wire on my chevy and relays and such. I think I like the ignition switched set-up best.  The problem is I don't have an unused fuse position in my panel.  There is a place for a fuse to plug in but there are no metal contacts in this position (#22) in the fuse block.  The orange aux wire ends up under the hood near the master cylinder.  This makes me think they want you to hook into the fuse and relay block under the hood. There are two nice 30 amp threaded posts in there marked aux A and aux B. The problem with these is they are "HOT"  even with the key off.  Am I missing something?  Do I have to add a position to the dashboard fuse panel?  How do I do this? I can't even see up there never mind  get my hands up there. Or is my best(and cheapest) option to put an inline manual switch on the orange wire, or just simply unplug. The problem is remembering to do either. My tv is a 1998 chev K1500.  Any thoughts or help would be greatly appreciated.  Please don't leave out any of the details. thanks

[XJJoe01]

I'm looking through old posts trying to get the best set-up for charging my battery while towing. I have gotten a lot of info here like the orange aux wire on my chevy and relays and such. I think I like the ignition switched set-up best. The problem is I don't have an unused fuse position in my panel. There is a place for a fuse to plug in but there are no metal contacts in this position (#22) in the fuse block. The orange aux wire ends up under the hood near the master cylinder. This makes me think they want you to hook into the fuse and relay block under the hood. There are two nice 30 amp threaded posts in there marked aux A and aux B. The problem with these is they are "HOT" even with the key off. Am I missing something? Do I have to add a position to the dashboard fuse panel? How do I do this? I can't even see up there never mind get my hands up there. Or is my best(and cheapest) option to put an inline manual switch on the orange wire, or just simply unplug. The problem is remembering to do either. My tv is a 1998 chev K1500. Any thoughts or help would be greatly appreciated. Please don't leave out any of the details. thanks

Find a ignition only power source like the radio and attach a relay.  The relay will tie the the ignition to the 30 amp battery feed.  
 
The relay will allow the 30 amps to the trailer battery when the ignition is on.
 
Quick diagram:
----ignition power ----->trigger input to relay
---30 amp battery feed--->switched input on relay
-------to trailer-----------<--- relay switch output (30 amps)
 
Joe

[ccarr113]

Find a ignition only power source like the radio and attach a relay.  The relay will tie the the ignition to the 30 amp battery feed.  
 
The relay will allow the 30 amps to the trailer battery when the ignition is on.
 
Quick diagram:
----ignition power ----->trigger input to relay
---30 amp battery feed--->switched input on relay
-------to trailer-----------<--- relay switch output (30 amps)
 
Joe

I need more details!!!! Do I drill a hole in the fire wall and feed the orange wire through and connect it to the source?  The fuse for the radio,as you suggest is only 10 amps.  What good is that for a 30amp feed? That just doesn't seem right. What I need is for someone to walk me through this step by step.  I'm a dedicated DIYer and I'm sure I can handle the job, but I need to know exactly what to buy and exactly how to hook it up. Your "quick diagram" is not DETAILS.

[howlinowl]

I need more details!!!! Do I drill a hole in the fire wall and feed the orange wire through and connect it to the source?  The fuse for the radio,as you suggest is only 10 amps.  What good is that for a 30amp feed? That just doesn't seem right. What I need is for someone to walk me through this step by step.  I'm a dedicated DIYer and I'm sure I can handle the job, but I need to know exactly what to buy and exactly how to hook it up. Your "quick diagram" is not DETAILS.

A relay is an electric switch.  It has two separate circuits, a control circuit and an load circuit.  The control circuit consist of the switch, (in this case, the ignition switch) and the magnetic coil of relay.  The load circuit consists of the relay switch (which is closed by the magnetic coil of the relay) and the load (which is in this case the battery of your PU.)

The reason that the 10 amp fuse will work for the control circuit is that the magnetic coil in the control circuit does not pull that much amperage.  When you turn on your ignition switch, the control circuit closes, supplying current to the magnetic coil of the relay.

The magnetic coil, pulls the relay switch closed, closing the load circuit.  This supplies the current to your PU battery to allow charging.

Your car horn works the same way.  You press the button, closing the circuit to the magnetic coil of the horn relay, suppliing current to the magnetic coil of the relay (control circuit).  The magnetic coil, pulls the electric switch closed, completing the circuit to the car horn (load circuit).  

The starting circuit in your TV works the same way. This allows you to operate a large amp drawing device like your starter from inside your car using a lower amp drawing device such as a starting relay.  No need to run those big honkin' cables into the passenger area to the switch when we can just run some smaller wires.

Not sure if a horn relay would work for a relay to allow charging of my PU battery, I will do this mod in the future, but for the time being we are camping where they have full hook-ups, so no rush yet.

Allan

[howlinowl]

Here's a wiring diagram from another site.  This guy is building his own teardrop trailer and has posted the diagrams on wiring his trailer.  He has another switch in the control circuit to allow him to kill the control circuit when he has his TV running and the trailer disconnected.  Good idea, I'll do this when I wire mine. He calles the relay a solinoid.  Same thing.  

http://www.asolidfoundation.com/dd_electrical.shtml

allan

[ccarr113]

Here's a wiring diagram from another site.  This guy is building his own teardrop trailer and has posted the diagrams on wiring his trailer.  He has another switch in the control circuit to allow him to kill the control circuit when he has his TV running and the trailer disconnected.  Good idea, I'll do this when I wire mine. He calles the relay a solinoid.  Same thing.  

http://www.asolidfoundation.com/dd_electrical.shtml

allan

Ok, so what do I buy for a relay(solenoid)? Are there different sizes? Do I go into the parts store and say "gimme a relay for a 1982 ford bronco" or what? I also still don't know how I will tap into the fuse block.  As I stated in my original post, I can't even see up in there let alone get my hands up there to do any work. I have seen a thing called an "add a line"
but I didn't really study it too well.  Isn't the fuse panel "HOT" all the time?  Do I splice into a wire leading to the radio, then drill a hole in the fire wall? These are some of the details that I need.

[tknick]

I'm looking through old posts trying to get the best set-up for charging my battery while towing.  I have gotten a lot of info here like the orange aux wire on my chevy and relays and such. I think I like the ignition switched set-up best.  The problem is I don't have an unused fuse position in my panel.  There is a place for a fuse to plug in but there are no metal contacts in this position (#22) in the fuse block.  The orange aux wire ends up under the hood near the master cylinder.  This makes me think they want you to hook into the fuse and relay block under the hood. There are two nice 30 amp threaded posts in there marked aux A and aux B. The problem with these is they are "HOT"  even with the key off.  Am I missing something?  Do I have to add a position to the dashboard fuse panel?  How do I do this? I can't even see up there never mind  get my hands up there. Or is my best(and cheapest) option to put an inline manual switch on the orange wire, or just simply unplug. The problem is remembering to do either. My tv is a 1998 chev K1500.  Any thoughts or help would be greatly appreciated.  Please don't leave out any of the details. thanks

If your chevy is already equiped with a wire (whatever color aparently yours is orange) that runs from the charge pin on your trailer plug to the battery/alterantor but you don't have power, you may just need to add a relay to the fuse block under the hood.  that is the way my Ford was set up.  It came all pre-wired, but for some reason I had to install the supplied relay in the fuse box under the hood.

If you don't have the wire running from your trailer plug, you will need to run one.  I am guessing 12 gauge wire would be sufficient, but you will need to check on that.  As for the relay, you can buy a 30 amp relay from any part store.  I bought one for about $6.00 for use on a different project.  If you can find a 12v switched source under the hood, you can tap that for the trigger on the relay.  If not, you will have to tap one under the hood and run it throught the firewall to the relay.

Assuming you have to do everything yourself, a typical set up would be relay relay mouted to the fender wall or firewall near your battery. A sufficient gauge wire running from your battery's positive terminal to the relay.  A sufficient gauge wire running from the relay to the charge pin on your trailer plug running under the frame of the truck avoiding anything that moves or gets hot.  Another wire running from the relay to a frame ground on your truck.  The last connection would be a trigger wire that is tapped from any 12v source that is hot only when the ignition is on.  Finding one under the dash is the easiet, but like I said, you will have to get it through the firewall.  The trigger wire does not have to be as heavy a gauge as the other wires.  16 or 18 gauge would probably do.

I am not an electrician.  I would recommend asking the guy at the part store what the proper wire sizes would be.  Otherwise you could probably search on the web and find out.

this is a basic setup.  if something isn't clear, let me know and I will try to clarify.

[wynot]

On a Chevy truck, the Aux 1 is the tap for the trailer 12 V wiring. My Chevy, although equipped with the heavy duty tow package, didn't have power to the 12V pos connection. All it needed was a fuse to be put in.
 
Although I understand that why someone would want a switched circuit, but I gotta tell you, it has never been an issue with us.  If I know that I am going to be parked for more than 15 minutes, but not over an hour,  I will pull the bargman connector to the camper, and let the fridge run off the camper battery.

[ccarr113]

On a Chevy truck, the Aux 1 is the tap for the trailer 12 V wiring. My Chevy, although equipped with the heavy duty tow package, didn't have power to the 12V pos connection. All it needed was a fuse to be put in.
 
Although I understand that why someone would want a switched circuit, but I gotta tell you, it has never been an issue with us.  If I know that I am going to be parked for more than 15 minutes, but not over an hour,  I will pull the bargman connector to the camper, and let the fridge run off the camper battery.

I'm all set now.  I figured it out.  I picked up a relay used for fog lights at the parts store,  the guy said it would work. Thank you all for your input and help. It wasn't too bad of a job once I got started and looked around under the dashboard.  Im addicted to this forum.  thanks again!!