We have a 1200W MSW inverter and use it to run our 900W coffee pot off 4 AGM batteries (440AH). The biggest problem encountered is the voltage drop due to the current draw - it might cut off the inverter. With 4 batteries, we see a .5V drop in the morning when brewing coffee. At that time, we are typically at 75 percent battery charge. The voltage on the batteries drops from 12.5V to 12V then returns to at least 12.4V when the coffee maker is done. Our inverter is set to cut off at 11.9V. The amp usage of the coffee maker during its cycle is 11AH but it pulls up to 100A while brewing. With only two batteries you will probably have a greater voltage drop which may make your inverter shut off.