OPERATION
BATTERY CHARGING WITH MULTIPLE INVERTERS
The inverters can operate in parallel as battery chargers from the same AC source connected to the same battery. The AC input terminals and DC terminals would all be in parallel. The inverters will synchronize individually to the AC source and then connect.
When multiple inverters are connected to the same battery and operated as in battery charger mode, the settings of the inverters are best set to the same settings. Only when a system is being operated in automatic generator control mode should staggered settings be used.
The most significant problem with multiple inverters charging the same battery is the voltage ripple caused on the battery. This causes the chargers to not reach their full output - two battery chargers on the same battery may not provide twice the charging rate to fill the battery in half the time. The higher the charger rate and/or the smaller the battery, the more pronounced this problem would be. The only way to reduce the problem is to individually cable each inverter and to connect them at opposite “corners” of the battery bank. Keeping the cable size as short as possible also helps.
Since the inverters will all be charging the same battery, one inverter may taper off first and finish the bulk stage before the others. When a single inverter has reached the float stage, it is best to turn off the generator at this time. It may take a longer period of time for the remaining inverters to reach the float stage. Running the generator to only power an inverter that is float charging is very inefficient and should be avoided.
If multiple Battery Temperature Sensors are installed, ensure they are all connected to the same location (battery). This will also help prevent one inverter from tapering off first.
AUTOMATIC GENERATOR CONTROL WITH MULTIPLE INVERTERS
Several considerations must be taken into account when using the automatic generator controlling system with multiple inverters. The inverter that controls the generator – referred to as the “generator controlling” inverter - along with the other inverter which does not control the generator - referred as the “non- generator controlling” inverter - must be programmed differently to achieve the best results. The two inverters should be programmed with the same BULK VOLTS DC and FLOAT VOLTS DC settings, but with the ABSORPTION TIME on the
The same consideration should be made if you are trying to equalize the batteries. The two inverter/chargers should be programmed with the same EQUALIZE VOLTS DC settings, but with the EQUALIZE TIME on the
If you manually equalized your batteries – by using a manually started generator or utility power - the FLOAT LED will come on to indicate that the equalization process has finished. You must return the cursor to the OFF position in the SET GENERATOR menu item on both inverter/chargers once the equalization period has been completed.
If the automatic generator control system is used to equalize your batteries, the equalization process will begin during the next - automatically started - generator run period. When the equalization period has been completed, the generator will automatically stop and the cursor under the SET GENERATOR menu item will return to the AUTO position on the “generator controlling” inverter. At this time, you must manually return the cursor in the SET GENERATOR menu item on the
2001 Xantrex Technology, Inc. | Telephone: | SW Series Inverter/Charger |
5916 - 195th Street N. E. | Fax: | Part No. |
Arlington, WA 98223 | www.traceengineering.com | Rev. C: February 2001 |
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