Inductive loads, such as TVs and stereos, require more current to operate than do resistive loads with the same wattage rating. Induction motors, as well as some TVs, may require two to six times their rated wattage to start up. Because the MAXX SST™ inverters have a peak watt power rating, many such appliances and tools may be safely operated. The equipment that needs the highest starting wattage are pumps and compressors that start under load. This equipment can be safely test- ed. If an overload is detected, the inverters will simply shut down until the over- load situation is corrected. Use the front panel switch to turn OFF the inverter, then ON, to reset the inverter.
CAUTION: NO
4.2 DETERMINING BATTERY SIZE:
To determine the minimum battery size that you will need to operate appliances from MAXX SST™ Models, follow these steps:
1.Determine the wattage of each appliance and/or tool you will need to simultaneously operate from the inverter. To do this, read the labels on the equipment to be operated. Usually, power consumption is shown in watts. If it is shown in amps, multiply by 110 to determine the wattage.
2.Estimate the number of hours the equipment will be in use between battery recharges.
3.Determine the total
To get an estimate of the current (in amps) that the battery must be capable of delivering, divide the load consumption power (in watts) by (10). Keep in mind that most appliances are not operating for long periods of time. For example, a typical
4.3 BATTERY OPERATING TIME
FIGURE 6 is a set of curves that show how appliance load in watts or in amperes affects operating time. These curves are only estimates of operating time, dependent upon:
•The condition of the batteries
•The state of charge on the batteries
•The amount of other DC appliances drawing current from the batteries
Three curves were developed for a battery of 50 Ampere Hours (AH) capacity, and three for multiple batteries in parallel. The higher capacity curves are for 120 AH, 200AH and 400AH capacities. These large capacity batteries clear- ly extend operating time at full load. To extend operating time in general, reduce the heavy appliance load to a minimum. Remember, you are operating on stored energy and probably under power loss conditions. All operating time curves assume permanent installation with the correct DC input wire (See Specs Page 18) and a full charge on the batteries.
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