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I just thought to share a comment on alternators producing higher output at idle than normal. Higher internal heat can be generated at idle and some alternators can overheat at idle since the internal cooling fan(s) are turning more slowly. Likely less of an issue with diesel engines at idle that generally do not operate at as high of an RPM as gas engines when traveling on the highway where pulley sizes may vary affecting alternator RPM’s. Although we had to upsize some diesel-powered forest service type vehicle alternators to large case 200-amp bus alternators to withstand the heat of electrical loads and constant idling in the field. And our patrol car alternators in my career suffered shorter life spans due to high current loads and long idle hours, we referred to them as toasters, as many toasters operated at 1,000 watts. My experience is not meant to detract from any product or method of power production, only to share field experience of my automotive career.

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the most accurate and reliable method to determine precisely how much idle output capacity has been engineered into any vehicle, is the following. using a DC amp clamp meter measure the current on the alternator wire with the engine running but all vehicle accessories off. Then switch on all vehicle accessories, fan, lights, etc and measure again. the difference between these two numbers is exactly how many amps are available safely and with zero risk of strain to the alternator. SO then you can simply switch off all those vehicle accessories and instead pull out that same amount of power safely. Here is a good video demonstration. https://youtu.be/Js4K6N5rMCg

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Just thought there may be interest in this. We have a 2018 Tiffin Allegro Bus AP40 with a Cummins 450 HP diesel engine. It is an all electric coach with a residential refrigerator. I wanted a faster way to charge our 810 Ah lithium battery bank while driving. I designed and just installed a new single alternator charging system that automatically disconnects the starting batteries from the alternator and connects them to a DC-DC charger after the engine is started. The new alternator / programmable regulator is then free to charge only the lithium house batteries and power any other active DC loads, while driving down the road. It charges at 14.5 Volts, a charge current of around 300 Amps and brings the batteries back to 100% state of charge (SOC) and zero amp hours consumed as shown on the Victron 712S monitor. It takes less than one and a half hours to recharge the battery from a 50% SOC (405 Ah consumed) to 100% SOC when on the road. The system required designing and building a special controller system which interfaces with the Spyder Controls multiplex networking system. We are currently on a trip from Washington state and now in Arizona, and it is working flawlessly.

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One of the questions asked was if you really need a DC DC charger when your truck has lead acid bats and your trailer has lithium. here is the answer which may be helpful for others. You are only plugging in the 7 way pin connector, and do not want to run extra cables through your brand new vehicle.

Your truck has lead acid batteries, and your trailer has lithium batteries and because of the difference in voltage and charging rates etc it is best to install a DC DC charging unit in your trailer, BUT you still will just use the 7 way pin connector. This will keep your battery systems safe on both sides, and you don't need to install any additional wires in your brand new vehicle. Everything is installed and done in your trailer only. The downside is that you will get a much smaller amount of power from your truck, which it sounds like you are ok with. At some point in the future you can get the heavy duty cables installed in your vehicle and then get about 10 times the amount of power recharging your trailer while you are on the road.

Here is an excellent article explaining this by a very reputable source that I trust and have known for years.

https://amsolar.com/rv-solar-news/do-you-need-a-dc-dc-charger-on-your-7-pin-connector/#:~:text=A%20DC%2FDC%20charger%20installed,to%20lower%20voltage%20starter%20batteries.

YES we are offering the Mike Sokol discount on all of our CarGenerator Allweather models including the larger ones. With your truck and alternator you could go with the 1500w (or the 2000w if you are able to put your truck in high idle mode)

Use the code below at checkout to save $150

MIKESOKOL150

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the most accurate and reliable method to determine precisely how much idle output capacity has been engineered into any vehicle, is the following. using a DC amp clamp meter measure the current on the alternator wire with the engine running but all vehicle accessories off. Then switch on all vehicle accessories, fan, lights, etc and measure again. the difference between these two numbers is exactly how many amps are available safely and with zero risk of strain to the alternator. SO then you can simply switch off all those vehicle accessories and instead pull out that same amount of power safely. Here is a good video demonstration. https://youtu.be/Js4K6N5rMCg

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Better than losing food or heat in an extended outage. Just wish it didn't require burning fossil fuel to do is job.

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True, but if you have solar and the sun doesn’t shine for a few days you’re kinda stuck…

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I couldn’t make it to your webinar but watched the replay last night and enjoyed it. Thanks Mike!

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