Iris Technology Operator's Manual
QuietPower 1800 (QP-1800) Doc 287.F701 / 100412
Appendix B
TECHNICAL ADDENDUM
This technical addendum has been prepared to address concerns raised in regards to degraded
inverter performance specifically: shortened runtime - in the field. Root cause investigation has
revealed that in cases where the inverter malfunction is not the cause, vehicle condition and
environmental factors can severely affect the function and performance of the inverter.
B.1 QP-1800 Performance with Vehicle and Environmental Factors
The performance of the QP-1800 inverter can be affect by external factors:
Temperature (battery)
Age and condition of the vehicle battery & charging system
Condition and integrity of the vehicle cabling
B.1.1 Temperature Effects on Battery Performance
Cold temperatures decrease the output and efficiency of the vehicle battery, and thus the ability
of the inverter to draw power from the battery will be limited. Figure 13 shows typical runtime in
hours over various temperature ranges. Users should be aware that the output of the vehicle
battery and inverter will be shorted in cold weather conditions.
Figure 13: Runtime hours vs Amps Over Temperature