Electrical wiring questions.

[Tango Sierra]

I have purchased several upgrade products for my 2010 FJR including an Eastern Beaver PC-8 Fuse Panel which I will install under the passenger seat. I plan to set it up as follows:
swtiched
1. Radar Detector
2. McCruise Control
3. Powerlet Tank Bag connections
4. Clearwater Krista & Glenda LED lights
5. Heated grips
6. Powerlet connection for Heated Clothing
unswitched
7. Cigar lighter and a Connection for M/C Battery Charging
8. GPS

I will install an external on/off switch for circuit #7.

I have on hand three rolls of 16 gauge wire in different colors. Is 16 adequate or should I use 14 gauge for any of these applications?

I plan on running the fuse panel's 50amp wiring harness for power to the battery along the right side of the frame and the rest of the wiring to the accessories from the fuse panel along the left side of the frame to the front of the bike. Does anyone see this causing any problems.

Also, many of the wiring harnesses that came with the accessories have fuse holders because they were designed to hook directly to the battery. Since I am connecting these items to the new fuse block, can I leave the in line fuse holders in place, which will double the fuses in the circuit but save me from having to make new connections after cutting out the inline fuse holders?

 

[Fred W]

Wire gauge is determined by what load you'll be putting on each circuit. The ones that I would be most concerned with would be the heated clothing and to a lesser extent the heated grips.

Your 16 gauge wire is good for about 13 amps of current in an enclosed, unventilated space. At the FJR nominal 14 volts, that would mean that you could power up to about 180 watts on a circuit with 16 gauge. If your total heated gear being powered off that one circuit will exceed 180 watts you may want to up the wire size to 14 gauge. 14 gauge is good for 17 amps or about 240 watts of load.

Yes, you can leave the inline fuse connectors, if you want. But you may want to be strategic about what fuses you put where, just for you own convenience. You may want to intentionally put a bigger one in the inline fuse holder so you know where to look when the fuse blows (in the panel) and can essentially ignore the inline fuses. The entire circuit will be protected adequately by the fuse in the fuse panel.

No problem running your power feed down one side of the bike and the device wiring on the other. Many people use one side or the other and just use the same wire loom (for chafing protection) but that is just their choice, not a requirement.

 

[RiderX]

Can't go wrong with Fred's advice, but for DC applications it is a little conservative. The current ratings are for NEC wiring of 120V AC homes (really anything under 600v in building wiring). You have no problem running 16 gauge for the items above if the runs are short.

(Edit wrong table)

I DO like to upsize 15% for engine compartment wiring as the DC tables are usually for 30 degrees C and it is about 15% to accommodate 50 degrees C

You can search current capacity 12V (or somethingsimilar) and find similar tables for mobile use. Here is one: https://www.offroaders.com/tech/12-volt-wire-gauge-amps.htm

There is also an app called wire sizer for iDevices, but it is fairly lame and will cost you a buck. As Fred mentions, wire sizing for 14V is a good idea as well.

 

[RossKean]

When it comes to heated gear, you may be able to get away with a smaller gauge since ratings are for continuous draw. Heated gear cycles on and off so a time-weighted average is usually far less than the maximum draw. Having said this, there is no reason to skimp on wire size! Specifications already have a fair safety factor built in but if I am anywhere near the limit, I go to the next size.

 

[Tango Sierra]

Thanks for the recommendations. I will use the harnesses that came with the accessories where they are long enough and for the heated clothing I'll go 14 gauge and 16 for the rest.

I'm going to fuse the PC-8 circuits as follows:
30 amp swtiched harness
1. Clearwater Krista & Glenda LED lights (7.5 amps)
2. Radar Detector (2 amps)
3. Heated grips (4 amps)
4. McCruise Control (3 amps)
5. Powerlet Tank Bag connections (3 amps)
6. Powerlet connection for Heated Clothing (10 amps)
20 amp unswitched harness
7. Cigar lighter and a Connection for M/C Battery Charging (15 amps)
8. GPS (5 amps)

I tried to keep the total amps of the individual fuses no more than the amp size of the harness fuse yet allowing the amp rate of the individual fuse to be just over the draw listed on the accessories. Am I being too conservative with my fuse sizes? For instance, the heated grips draw max 40 watts (less than 3 amps) so I figured 4 amps for the fuse. The switched fuses I planned total 29.5 amps which is 0.5 amps less than the harness 30 amp fuse.

Also, am I over stressing the alternator with all these add-ons?

 

[Fred W]

As long as the fuse size you select is larger than the device's current draw, and smaller or equal to the maximum rating that the wiring can handle, you'll be fine. It is not uncommon for the total of the sub-circuit fuses to add up to more than the main input fuse rating because of the added margin in each of the individual circuit fuses.

As for what your alternator can handle, your second gen alternator has a total output rating of 590 watts. The stock bike uses ~ 360-370 watts, so you have spare capacity of a bit over 200 watts.

You'll want to add up the actual power requirements for each of your devices and ensure that it is not more than that. If it is, you'll notice the voltage will droop and you'll have a battery that is discharging as you drive. The best way to avoid that is to install a panel voltmeter of some type and wire it directly to the battery terminals. You can use a switch or relay to enable.disable it. But don't take the voltmeter's voltage signal from your fuse panel as the voltage in the fuse panel may drop under heavy loads before the battery charging voltage does. It's the voltage at the battery that you care about.