Question about voltage output and the SH847AA rectifier

PaddyO said:

I will check with a volt meter. I have been watching this occur over the past week since I installed the SH847AA. I believe the CVS works with both lead acid and lithium batteries.

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PaddyO said:

I replaced the stock rectifier on my 2014 R3T with the SH847AA Suzuki rectifier. I have the Clearwater Voltage Sentry also mounted on the bike. The CVS monitors the condition of the charging system. it uses a single LED to indicate the state of the system. From their website:

Flashing Red: Indicates Less than 11.5 volts (12.7 volts on Shorai battery). This is not a good condition for the battery, and could indicate a starved or defective battery. Get a charger on this battery immediately and check to see if it will come back to life.

Solid Red :Indicates between 11.6 and 12.0 volts (12.7 and 12.8 volts on Shorai battery). Weak battery, start and run the engine for a while or get a charger. If this persists after charging, the battery needs to be replaced. If this occurs while the bike is running, your alternator is bad or severely overloaded.

Solid Yellow: Indicates between 12.1 and 12.4 volts (12.9 and 13.1 volts on Shorai battery). This indicates the battery needs to be recharged. If this occurs while the bike is running, it means you are drawing a lot more power than the alternator is generating, and potentially a bad alternator.

Solid Green:Between 12.5 and 13.1 volts (13.2 and 13.4 volts on Shorai battery). Good battery condition with the bike off; poor to weak charging condition with the bike running. This can also indicate your accessories are drawing too much power. Note: some bikes do not generate sufficient power at idle. This can be normal. If you get the solid green light while your bike is idling, run the engine faster and it should start flashing green.

Slow Flashing Green :Indicates between 13.2 and 14.6 volts (13.5 and 14.8 volts on Shorai battery). The battery is charging properly.

Fast Flashing Green: The battery is over 14.6 volts (14.8 volts on Shorai battery). This indicates an abnormal overcharging situation that could indicate a faulty alternator. Get your electrical system evaluated immediately.


With the OEM rectifier, I always had a Slow Flashing Green light on the CVS with the engine running. Since installing the SH847AA rectifier, after starting the bike, the LED will be a Fast Flashing Green. After riding the bike for a while (20-30 minutes?), the LED will change to a Slow Flashing Green. Also, when turning on the bike, the LED will be yellow whereas with the OEM rectifier, the LED was green.

Is my battery going bad? Is it a coincidence that this change occurred after installing the SH847AA? Is the SH847AA causing a problem with my charging system?

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Ted Biggie said:

Sounds like the battery is on it's way out. It's discharging below 12.6 when it sits so when you initially turn the bike on, Yellow. Then you start it and voltage goes high as rectifier works to recover the battery. Fast flashing Green.

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PaddyO said:

Ted, I think you may be right. I have tested the battery several times now after letting it sit either over night or for 1-2 days. When I hook my digital volt meter to the battery before turning on the key, the voltage is from 12.5 to 12.6 volts. When I turn on the key, my volt meter says it is from 12.0 to 12.1 volts. My Clearwater Voltage Sentry (CVS) is a solid yellow indicating it is between 12.1 and 12.4 volts. This is with the LED headlight and running lights on. Upon turning on the engine and letting it idle, my volt meter is indicating 14.6 volts. The CVS is flashing a slow green indicating it is between 13.2 and 14.6 volts. When I increase the idle to 1,500 RPM, the voltage goes to 14.72 volts. The CVS starts a fast flashing which indicates more than 14.7 volts.

From what I have read online, 12.4 volts at rest indicates the battery is at about 75% charged. When I start the bike, the voltage drops to about 9.3 volts. Again, from what I have read online, this should be 9.5-10.5 volts.

According to the Clearwater Lights website, the CVS is appropriate for regular lead-acid batteries and Li-Fe batteries such as the popular "Shorai" batteries.

It appears I need a new battery. Agree? Disagree?

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Bedifferent said:

For me it is a difficult call. I would expect some voltage drop perhaps in the range of what you talk about with the key turned on as well as the lights. I have a little optimate tester that shows voltage before starting and during starting. It has hold LEDs that continue to illuminate after things are running so you can see what has happened and what is happening after the engine us running. A voltage drop down to around 9 volts is considered to be in the acceptable range. Your charging voltage appears to be good, but it does seem strange it doesn't show a full charge after a day or two of setting....Especially if it was charged fully. If something is draining the battery down I guess I would be looking for that. Do you have an alarm system on your bike or some other low current draw device on your bike. You may find this chart helpful.

A new and better battery my be the simplest choice to start with. I prefer a Yuasa myself. This AGM comes dry with the acid you put in so you will know you are starting out fresh.

Yuasa YUAM620BH YTX20HL-BS Battery

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PaddyO said:

I will take the battery to get load tested. I went into a battery plus store near me and they had a Duracell powersports battery that is the right size, 310 CCA, & 17.5 AH. It is made in the U.S. by East Penn Manufacturing. It comes with a 2 yr replacement warranty if it goes bad in that 2 yrs. Claviger likes it.

I don’t know what would drain the battery. The CVS draws almost nothing with the bike off. I do not have an alarm system. The bike is 4 years old and I do not know the age of the battery.

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