SmartGauge FAQ

Q 1. What exactly is SmartGauge?

A. Think of it as a fuel gauge for the batteries with a host of other added features.

Q 2. Why does SmartGauge go from 100% to 0% in just 2 hours with only a few lights on?

A. The batteries are faulty (full explanation here).

Q 3. During charging SmartGauge reaches a cartain charge status but never gets any higher no matter how long I leave the charger on. Why?

A. The charge voltage is too low and the batteries simply aren't being charged (explanation here).

Q 4. Can I use SmartGauge to monitor a 12 volt and a 24 volt battery bank?

A. No, because SmartGauge is designed to operate in conjunction with SmartBank which obviously requires both batteries to be the same voltage.

Q 5. On the whole SmartGauge agrees with my amp hours counter, but varies by about 10% to 15% throughout the range. Why?

A. Because SmartGauge shows the charge status as a percentage of the total energy remaining as opposed to the total amp hours remaining (see charge status).

Q 6. I fully recharged and SmartGauge showed 100%. Within 30 minutes the batteries were flat but SmartGauge still showed 50%. Why?

A. The batteries are faulty (full explanation here).

A. You are abusing the batteries with highly excessive discharge rates (explanation here).

Q 7. My battery bank is made up of some gel cells and some wet cells. Which battery type should I set?

A. You can't mix different battery types. SmartGauge won't work, your batteries won't work, your charger won't work

Q 8. Can I power another meter from the same power feed as SmartGauge?

A. No.........

Q 9. What will happen if I do?

A. SmartGauge won't work properly.

Q 10. SmartGauge counts down very quickly when the microwave is on, but then stays at the same charge status afterwards even though we are discharging the battery. What is going on?

A. SmartGauge is synchronising itself. It will catch up and be more accurate next time.

Q 11. Are the alarm terminals connected to anything inside SmartGauge?

A. No, they are completely isolated.

Q 12. When swapping from discharge to charge, or from charge to discharge, it is some time before the charge status starts to move. Why doesn't it move immediately?

A. SmartGauge uses this transitional period to measure the battery charge status and correct it's battery model and algorithm. This is what prevents SmartGauge running out of synchronisation with the batteries. SmartGauge will "catch up". It may also be that the charge or discharge is at a very low rate in which case changes in charge status will be very slow.

Finally it may be that following a charge or discharge, the battery charge status is subject to variation as a result of surface charge or discharge and the changes in charge status as a result of this are balancing the changes in charge status due to the present load or charge rate. See Q14 below.

Q 13. SmartGauge doesn't show the true state of charge of the batteries. What is going on?

A. Assuming you have set the correct battery type then "Says who?" What are you comparing it with? Nothing else works. Assuming you are comparing it with an SG reading then you did remove the batteries and shake them up or vibrate them for 30 minutes didn't you? You did also read the section explaining why and how SG readings will not show you the state of charge? (in FAQ page one - How can we tell the state of charge of a battery?).

Q 14. Why does SmartGauge continue counting up the charge status even after the charger has been switched off? Surely this can't be correct?

A. Yes it is perfectly correct. Immediately after the charger is switched off, there is less available energy in the battery than if you wait a short while before discharging. This sounds ridiculous but it is indeed the case. There is a full explanation here.

Q 15. Why does SmartBank stay connected after I switch the charger off or shut the engine down?

(Note that this reply applies to SmartBank Standard and the SmartBank Advanced/SmartGauge combination)

A. There are two schools of thought on when the relay should be connected. One school is the "I only want the relay connected when I am charging" school. The other school is "I want the relay connected all the time except when I am discharging". A further extension of these are those who wish to use some of the engine start battery capacity to supplement the auxiliary bank but for it to be automatically separated out when the charge level drops down to a certain state of charge to keep enough power for engine starting. In this case, the relay will remain connected even when using the batteries under quite heavy discharge but will still separate out the engine start battery before the level drops to a state where starting the engine may become a problem. Neither school is right or wrong. Though you may personally think the other school is!

The default settings for SmartBank Standard and SmartBank advanced are somewhere between these two extremes as these settings suit the majority of applications. Therefore when the charger is switched off, the relay will remain connected for some considerable time (sometimes days in the case of my own boat), it all depends how much load is put on the batteries following the charge. SmartBank can be set to either extreme simply by increasing or decreasing the connect and disconnect voltages. This is achieved with the physically adjustable presets in the case of SmartBank Standard or in the SmartGauge setup menu for SmartBank Advanced.

SmartGauge FAQ


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Page last updated 02/04/2008.
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