Clearwater Voltage Sentry (CVS) Battery Monitoring Device
We and Clearwater wanted a simple voltage monitor for motorcycles to warn of any undercharge conditions. On touring motorcycles, it is important for to know how much power a motorcycle really has available. We and our customers often add many electrical accessories such has heated clothing, GPS units, auxiliary lights, HID lights, heated grips, heated seats, Bluetooth headsets, radar detectors, etc. so it is critical to know and monitor our battery's condition. Simply mount the control unit under the fairing and mount the LED indicator in rider view and you will always know the condition of your battery while parked and while riding. Adventure touring motorcycles, like BMW GS's and many others, can benefit greatly from this voltage monitoring device.
Clearwater Co. recently purchased a Suzuki DR650 project bike. The idea was to outfit the bike with Clearwater lights, heated grips and garment outlets. Clearwater wanted a way to determine when the factory electrical system would be overloaded, so they strapped on a digital volt meter with a bungee cord and rode around town. As this was not a practical solution, Clearwater purchased a few LED volt meters found in auto parts stores and online retailers.
In testing the purchased volt meters, Clearwater found them not only inaccurate, but they were unable to find any that matched results. In fact, none matched Clearwater's calibrated HP power supply - some were 10-15% off. In further testing, Clearwater put them in the freezer and found the accuracy further compromised.
Time for the digital age. Clearwater set out to design the best and most accurate voltage minder for not only motorcycles, but any vehicle with a 12 volt battery and charging system. Clearwater used a microprocessor based system of voltage measurement to illuminate a single LED in three different colors and with six different display voltages.
Clearwaters design goals were to provide a product that had a very low power consumption, would be simple to use, maintain thermal stability, accuracy, reliability, and flexibility. As is the case with most of their products, Clearwater used a digital design where they were able to tailor all aspects of the design in software. Calibration is completed on a lab bench upon initial activation against a very accurate 12.000 volt source. Each processor learns this voltage and makes all subsequent measurements against this programmed value. No varying resistive voltage dividers and wide tolerance transistors here. All of this in a voltage meter the size of a matchbox.
A simple two wire connection is all that is needed. One connects the unit directly to either constant power or switched power. A clever "power down" routine is designed into the device to eliminate any excessive power usage. The indicator LED is only illuminated when either the engine is running (thus indicating a charging system status) or for a short time period after the engine is turned off. After the device determines that the engine is now off, it initiates a timed sequence to display the battery voltage for short period (5 minutes). Then it shuts down the LED (saving what little power is used by an LED). The computer constantly checks for any change in voltage that would indicate a need for a "re-display" of voltage status. The computer uses only microamps of current to perform this "sentry" duty. Far more power is lost in the battery due to natural self discharge. So, when the engine is off, the sentry displays battery voltage. When the engine starts, it displays maximum system voltage. There is no need to make separate battery and alternator connections with our system. If you want to review the battery voltage, just turn on the key for a second and the computer will instantly wake up and light the correct color LED. Now you can monitor both without fear of draining the battery. The simple to mount CVS displays all three colors needed.
Wide temperature variations are common on outdoor vehicles and Clearwaters design is impervious to any "human" survivable temperature. From -40 degrees up to 200 degrees, Clearwaters CVS is dead solid accurate.
Without strapping a high quality Volt meter onto the triple clamp and monitoring voltages around town, the CVS allows instantaneous monitoring of your battery/alternator system. This system is the most accurate voltage monitoring device of its kind anywhere. Accuracy is better than 1/4 of a percent.
The Clearwater Voltage Sentry is a very useful and accurate tool to monitor voltage. If the light is green, you are good to go; yellow means there is a slight cause for attention. A red light conveys that your battery is definitely not charging; shut off accessories one at a time until you get a green or slow flashing green condition. If you are running a pair of Clearwater Krista Lights on your bike (total power usage 72 watts) you might only need to switch off your high beam to lower your power usage while stopped at a light. Once you get moving again (and spinning your alternator faster) you can switch back to high beam or the high setting on your heated garment.
You can very easily tell if additional accessories are drawing more power than your bike can supply. A simple Green/Yellow/Red LED displays 6 stages of battery voltage.
Flashing Red: Indicates Less than 11.5 volts. Not a good condition for any battery. Get a charger on this battery ASAP and check to see if it will come back to life. Chances are, it may need replacing.
Solid Red: Indicates between 11.6 and 12.0 volts. Weak battery, start and run the engine for a while or get it on a charger.
Solid Yellow: Indicates between 12.1 and 12.4 volts. Acceptable battery condition, Poor to weak charging condition.
Solid Green: Indicates between 12.5 and 13.1 volts. A good charging range.
Slow Flashing Green: Indicates between 13.2 and 14.6 volts. Excellent situation. Your alternator is doing it's job.
Fast Flashing Green: Indicates over 14.7 volts. Bad situation. The alternator is overcharging and may damage your battery. Have the alternator and or voltage regulator checked immediately.
All you have to remember is: "GREEN IS GOOD"
Vibration is not an issue as all of our parts are securely mounted directly on a high quality multi-layer PCB. To further improve reliability, each assembly is sealed in epoxy in an injection molded enclosure.
As this product is completely controlled by software, Clearwater can change all the parameters with code. If an application is needed for a different voltage indication range (say Li-ions in your new Tesla) Clearwater can easily make the change. Clearwater also have a voltage "map" for the new Li-Fe batteries such as the popular "Shorai" batteries.