Switched Power

Let me preface this by saying I always hated EE classes in college, so electrical stuff is usually a tough slog for me. But I've got a question, and I'll throw it out there despite it's potential ignorance.

I'm changing my Centech power block from unswitched to switched power, so I'm putting in a relay.

I'm using the "hot side" of the window auto retract (which I've previously disconnected) to activate the relay (per Bounce's writeup on his website)... and need to connect the return side. Could I use the other pin within the "window auto-retract" connector? If not, what would be a good place to go for ground? Directly to the battery terminal? I'll have some audio devices connected to this circuit, and want to avoid any alternator whine...

The battery is the best place to ground the Centech block, it should eliminate the alt whine. The FJR shunts excess alt power to the frame so do not connect your audio grounds to the frame.

Skooter had bad luck useing the windshield retract as a power source. It's on a 2 amp fuse and he's stated in the past that it kept blowing, but some guys have no problem at all.

I picked up switched power from the running lights.No blown fuses in almost two years, B)

Since all the window retract is doing is throwing the relay, I'm confused as to why that would blow a fuse....? :huh: Probably my electrical ignorance coming through.

I've grounded the Centech to the battery... I'm asking specifically about grounding the relay...

I'm not an EE either, but if all your doing is cutting the Auto Windshield loop and adding a relay, aren't you completing the auto circuit again , therefore the auto windshield feature would be back in operation again? I'd run all grounds to the same spot. ( I used a barrier strip for all hots, and another for all grounds, grounding the barrier strip the the battery ).

Now that I think about it, yes, you're right... that would be completing the circuit... pretty dumb. :blink:

Ok, here's another question... does the "exit" end of the relay need to be connected to anything? Will the relay throw without that connector grounded?

I use the retract as a power source for my switched power. One side is "ignition hot". It has something to do with the "loop" that we cut, which I could sit here and figure out and try to explain, but I just use it and it works.

On the '04, I used the marker light source as Highlander uses.

Madmike,

So what did you connect the other end of the relay circuit to?

My relay has 4 connection terminals.

+12VDC in

+12VDC out

Switched power in (front the window retract, running lights, whatever...)

and #4, which is the second side of the relay circuit.

It's the #4 terminal I'm trying to figure out. The Negative battery terminal seems like a good option at this point, unless I can leave it unconnected...

Once cut, the auto-park jumper will have one side of the loop hot when the ignition is on and 1 side "dead". Tape off the dead side and don't use it. Use the hot side to energize your relay. When done you don't complete the loop back to the auto-park so it remains where put when the key is off.

I have read several places (usually in installation instructions for electric componets) where it says not ground electric components to the negative on the battery, but to the frame. Why is that bad, or is it?

You said to ground audio components to the battery to prevent alternator noise. What about other electric components, e.g. DC outlets, etc?

Also, are you referring to the Centech Aux Power Fuse Panel? That is a pretty neat piece of hardware.

I have read several places (usually in installation instructions for electric componets) where it says not ground electric components to the negative on the battery, but to the frame. Why is that bad, or is it?
You said to ground audio components to the battery to prevent alternator noise. What about other electric components, e.g. DC outlets, etc?

Click to expand...

The FJR uses a charign system that shunts excess power to the frame. Because of that you do NOT want to use frame gounds for anything that is either "sensitive" (like a Power Commander 3) or for audio (it will put a hum into the audio).

You can run a ground block back to the negative terminal not a lot unlike a power distribution block. That keeps the battery terminals clean and free of clutter, gives you a place to run multiple grounds to an organized location (block), and avoid "floating" (frame) grounds for your accessories.

My PdB write up discusses the way I did a ground block. I've not updated it since I reran the main ground lead back to the negative terminal on the battery. Running it to the frame as in the desciption lead to hum in my music/audio. Running it back to the battery helped resolve that hum.

Bikes-N-Spikes

Groo,

pin 86 to auto retract switched power.

pin 85 to frame, battery neg, whatever. In THIS case ONLY it doesn't matter. What DOES matter is the quality of the connections! Don't worry about blowing the auto retract fuse, you only need milliamps to trigger the relay.

pin 30 to battery pos.

pin 87 to the input wire on your Centech block. It's not rocket science, just attention to detail that will give you results.

As far as questions about the lighter outlet....if you are using a CB radio, two-way or other type of system using audio that plugs into a lighter socket, wire the socket through the power block too. and DO NOT use the frame as a ground in this case! Go straight to batt. neg.

Thanks all...

As of yesterday, I now have switched power at the Centech, using the window auto-retract as the energizer for my relay. I put an inline fuse between the 12VDC supply from the battery and the relay, mounted it up front, and grounded (the relay) to the battery negative post. All works as expected, and I should have everything wired up and ready to go when the Mixit2 arrives late this week/early next week.

Now if my rotors would just get here, I could start digging into my Spiegler order...

Groo, where did you mount your Centech fuse box?

Right about here....

That looks good. I am planning on ordering the Centech this week. Did you order yours from Centech directly?

What is the black box in the lower left corner of your tool box?

What components do you have rigged into your Centech, and how did you decide what fuses (wattage rating) to use.

WOW , looks good. I just got my FJR last weekend and I see the need to get a Centech panel. Very nice. Anyone know the output of the charging system on the FJR and what the "normal" load on it is? Thanks, Rick M

I read that the peak charging power for a 2003 FJR1300 is 490 watts , and assume it is the same for later models.

Not sure about the opertating load, but I would estimate approximately 275 - 300 watts.

I thought this was interesting... For comparision purposes the peak charging purposes for the following comparable vehicles.

BMW R1150RT 700 watts

K1200LT 840 watts

Ducati ST2/ST4 520 watts

Honda ST1300 740 watts

GL1800 1100 watts mg2:

Suzuki V-Strom 360 watts :focus:

I ordered the Centech through Aerostitch.

Black box is the power adapter for my Valentine radar detector.

So far, what's plugged in are the V1, my magnum blaster horns. I'm going to hook up the XM Roady2 tonight, and the Mixit2 amp/mixer when it gets here next week. Still plenty of outlets for a GPS if I add that in the future.

What fuses to use? Usually there's info. on the power draw in whatever comes with the hardware. Since I'm not using anything with a huge power draw (no widder or heated grips or augmentation lighting), it's not a huge concern at the moment.