Q 1. What is SmartBank?

A. SmartBank is a "relay based" split charge system. That is to say it is based on the principle of paralleling batteries when they are being charged. An alternative view (they are both correct) is that the system is based on ensuring the batteries are separated when they are being discharged. Both views are correct.

Q 2. Isn't that the same as a split charge relay energised from the alternator?

A. It's similar, but in the case of SmartBank the relay operates wherever the charger is connected so it will split charge from the alternator, or an AC powered charger, or a wind turbine etc. It does this regardless of which battery bank the charger is connected to. Also bear in mind that many modern alternators do not have a suitable terminal to energise a relay from.

Q 3. So it's a voltage sensitive relay (VSR)?

A. It's similar. It works on a very similar principle. Sometimes these are also referred to as "battery combiners". However, SmartBank is far more sophisticated than a VSR which is why it operates so much better.

Q 4. So how does SmartBank know when to operate?

A. A simple VSR parallels the batteries when one of them rises to a certain voltage then disconnects them when they fall back down to another set voltage. SmartBank uses a combination of the battery voltage, the recent battery history and the rate of change of battery voltage.

Q 5. Is it complicated to install?

A. No, SmartBank is very simple to install as can be seen in this wiring diagram.

Q 6. What is the difference between SmartBank Standard and SmartBank Advanced?

A. Both units are physically identical and the installation is the same in both cases. SmartBank Standard is self contained and utilises it's own internal electronics to make the decisions and control the relay. All that is required is the SmartBank Standard control unit and the relay. SmartBank Standard can operate in conjunction with SmartGauge but it is not mandatory.

SmartBank Advanced is installed in the same way but requires connection to the SmartGauge battery monitor in order to operate. The vastly increased processing power of SmartGauge allows some advanced functions and features to be added to the split charge system such as full engine start battery priority charging and more advanced split charge algorithms.

Q 7. 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.

Q 8. Can I use SmartBank Advanced on it's own?

A. No, SmartBank Advanced will not operate without control from SmartGauge.

Q 9. How does SmartGauge control SmartBank Advanced?

A. Via a simple plug in RJ11 lead.

Q 10. I already have a SmartGauge installed and want to add a SmartBank to look after split charging. Which type of SmartBank should I use?

A. SmartBank Advanced gives more functions and is cheaper than SmartBank Standard. The installation is identical in both cases and therefore SmartBank Advanced makes more sense.

Q 11. I already have a SmartBank installed and want to add SmartGauge. What additional features will I get?

A. Remote indication of the status of SmartBank i.e. what it is doing. Remote "emergency connect" to enable engine starting from the auxiliary bank in an emergency. Error reporting if something goes wrong with the installation. Plus all the features of SmartGauge battery monitoring.

A. Alternatively you could modify SmartBank Standard to become a SmartBank Advanced as detailed here to benefit from the more advanced features such as full engine start battery priority charging etc.

Q 12. I have installed a SmartGauge and SmartBank Advanced on a twin alternator installation to allow the unused capacity from the engine start alternator to be diverted into the auxiliary bank. This works well and reduces the recharge time considerably however when the batteries get close to being fully charged one of the alternators shuts down, its charge warning light comes on and the warning buzzer beeps. How can I stop this?

A. Simple. Set the SmartBank high voltage disconnect to just below the voltage at which this happens. The split charge relay will then open and allow both alternators to operate independantly once the batteries are fully charged thus preventing this situation.

Web site and all contents Copyright SmartGauge Electronics 2005, 2006, 2007, 2008. All rights reserved.
Page last updated 14/08/2008.
Website best viewed on a computer of some sort.