Over loading electrical system

Outrider1

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My question is directed to the 750x.
I've read the 700x and now posing this question: I'm running Gerbing heated jacket liner 106 watts/14 volts, Gerbing heated gloves 18 watts/14volts and Sargent heated seat 23 watts/13.5 volts. Let's call it total 147 watts.

Can the 750 handle the above safely? What is the total capacity of the 750? Did or am I missing something?

P.S. Electrical is definitely not my strong suite.
 
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670cc

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My question is directed to the 750x.
I've read the 700x and now posing this question: I'm running Gerbing heated jacket liner 106 watts/14 volts, Gerbing heated gloves 18 watts/14volts and Sargent heated seat 23 watts/13.5 volts. Let's call it total 147 watts and 41 volts.

Can the 750 handle the above safely? What is the total capacity of the 750? Did or am I missing something?

P.S. Electrical is definitely not my strong suite.
Well, it’s not really relevant to the question, but there is no 41 volts. If the bike is putting out 14 volts, everything gets supplied 14 volts (assuming the generator is capable and the wire size is adequate). In simple terms, what adds up is the current draw, and consequently the power draw.

You say you’ve “read the 700x”. What does that mean? You’ve read all the posts about the 700x electrical power output?

I’m not aware of there being any change to the electrical power output of the 750 vs the 700. However, if the 750 has more LED lighting in place of incandescent lighting, that would leave more power available for accessory usage.
 
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Outrider1

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Well, it’s not really relevant to the question, but there is no 41 volts. If the bike is putting out 14 volts, everything gets supplied 14 volts (assuming the generator is capable and the wire size is adequate). In simple terms, what adds up is the current draw, and consequently the power draw.

You say you’ve “read the 700x”. What does that mean? You’ve read all the posts about the 700x electrical power output?

I’m not aware of there being any change to the electrical power output of the 750 vs the 700. However, if the 750 has more LED lighting, that would leave more power available for accessory usage.
I read as many as I found regarding what others have added but not found what total I can add to the capacity without going overboard and doing damage.
Looking through the owners manual didn't give me any info either.
 

670cc

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I don't think you will get any better answer than what has already been discussed. Even if there was a specified accessory power allotment, it still depends on a big variable: what RPM do you run the engine at? Low RPM, say 3000, will not put out the same power as say, 5000.

If I remember correctly, the power output is 440 watts at 5000 RPM. From that, you need to subtract wattage needed to recharge the battery, run the lights, fuel injection, ignition, etc. What's left is available for accessories.

You are probably OK with your suggested load. If in doubt, install a voltmeter on the bike, and monitor it. It will give an indication of whether there is still overhead to keep the battery charged. There won't be damage if you overload it, you'll just eventually drain the battery.
 

HarveyM

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I put a voltmeter on mine so I wouldn't have to worry about it. Tells you how the battery is before starting, monitors your charging system and tells you if the battery is charging/discharging while you're using your gear.
 

lootzyan

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As the 670cc said, at higher engine RPMs, the alternator generates enough energy to power an additional 150 W load. The problem begins at idle speed.
All battery charging systems are designed to be able to, with the engine at idle, provide power to the system and charge the battery, with a little reserve of energy. We don't know how much of this energy reserve is to power additional devices.
So it's best if you check it out experimentally. Invest in a Digital Clamp Meter Multimeter ($ 25- $ 45) that you will find very useful. Then temporarily connect all your additional devices to the battery and, with the engine running at idle RPM, measure the charging current, e.g. on a negative cable. Pay attention to the polarization of the current. Note the current polarization at higher engine speeds - then the battery is being charged. Then slow down to idle speed, leave it on for a few minutes, and observe that the polarization of the current does not reverse. If it does, this would mean that the battery takes over the power of the entire system and is quickly discharged.
It is good if the battery voltage is measured at the same time. Then you can determine the approximate threshold voltage when the charging current is reversed. It will give you a full picture of what you can expect.
 

dduelin

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Yes, heated gear is important at idle speed. Don't want to get cold sitting at a stop light.

I would invest in a voltage monitor that will give you an indication of the system voltage while you are riding (and at idle). It's there all the time and will indicate if the load is taking more than the charging system is able to give plus be an early warning of other electrical problems that might crop up in the future. The NC700/750s are designed and geared to run at rather low rpms at cruising speed and when riding is where you need to know if there is sufficient capacity to keep up with the electrical loads. There are a few motorcycles that won't pull the load of the three items you mentioned while at low rpms, I've owned a couple (the NC wasn't one of them), and what you had to do was turn down or off some of the heated gear when trundling along at low speed or at a stop. Or don't worry about a few moments riding slow when the charge current is in the negative. It won't drain the battery unless the load is like that for some period. At cruising speed there is enough amperage to run everything.

FWIW, the 700 creates minimum 420 watts at 5,000 rpm. Keep in mind you generally won't have all the heated gear on at 100% all the time so the actual operating load will be somewhat less than the maximum draw.

In practice my 700's and I assume the 750 has sufficient current to run a jacket and gloves at 100% even at idle. Mine would.

I installed one of these on the 2015: https://www.amazon.com/HEADS-VOLTAGE-MONITOR-SIGNAL-DYNAMICS/dp/B009H43B2O

And one of these on the 2012: https://www.clearwaterlights.com/products/clearwater-voltage-sentry

Both are quality kit and will do the job.
 

nicecruise

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I put a voltmeter on mine so I wouldn't have to worry about it. Tells you how the battery is before starting, monitors your charging system and tells you if the battery is charging/discharging while you're using your gear.
Any chance of a photo of said voltometer?
 

HarveyM

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Here it is; it's mounted on a 2 inch piece of angle Aluminium and tied into the electrical system via the Honda accessory harness & relay. The voltmeter itself is from amazon "Mictuning DC 12V LED Digital Display Voltmeter Waterproof for Boat Marine Vehicle Motorcycle Truck ATV UTV Car Camper Caravan Red Digital Round Panel" for less than $10.
 

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76Hawke

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Any chance of a photo of said voltometer?
Not the poster you asked, but this is another version that I just recently installed. It has a dual USB port that allows for fast charging of my smartphone with a Built-in Volt meter
 

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