NOTICE: I build these items in batches. Who knows when the next batch will be made. If you are in a rush, you may want to build it yourself.
This small LED voltmeter is designed for my motorcycle. If it is encapsulated in epoxy when done, so should be durable and waterproof and can be 'velcroed' almost anywhere. You will want to mount it low out of direct sunlight to make it more visible.
There are three LEDs, a red, green and yellow. The red only means your battery voltage is too low, red plus green means a little low, green only is normal, green plus yellow is a little high, and yellow only means too high.
You will find that if the red LED stays on it high RPM, you have a charging problem or too much load. If the Yellow LED comes on it is likely that the battery is low on water or you may be overcharging it.
This item sells for $25.
Often motorcycles have marginal charging systems. When you use a number of accessories such as driving lights and a heated vest, it is easy to exceed the charging system output, leaving you with a dead battery. Because I often enjoy fall and winter nighttime rides, I am using an electric vest along with extra lights to spot for any deer. My voltalert (see above) shows if the system is marginal.
This driving light controller may be the answer. It is intended to be connected through a fuse directly to the battery to drive the lights, just as you would a relay (and in fact replacing a relay). The difference is that as the voltage drops, so does the power to the driving lights. At about 13.5 volts, you are getting 100% power to the lights. At about 11.5 volts, you get about 0 power. At 12.5 volts you get 50% power.
You can add a second control input like the horns so your lights will come on when you press the horn button. Because this is a pulse width modulated system, it is very efficient. As the voltage drops and the power begins to switch, excess power should be diverted to the battery as charge current.
This unit will control a maximum of 110 watts (two standard 55 watt driving light bulbs).
NOTE: There is a chance that this system will cause audio noise in an on board radio system. I have not tested it. This package is NOT waterproof. The electronics is coated to prevent corrosion, and has simple heat shrink tubing over it. You need to mount it in a dry location. There is NO GUARANTEE for a water damaged module!
This items sells for $55.
Last update 02/10/09