Overview
Smart Distribution Panel with ATS 9
Fuel monitoring/runtime calculation
Fuel monitoring is a unique feature of the InfraStruXure Power Generation System. Fuel level is
monitored at the generator (if purchased through APC) and load is measured at the ATS. These
measurements are used to calculate runtime, as explained in the following paragraph.
Fuel is monitored by a level sensor in the generator fuel tank (calibrated to the bottom of the fuel
tank) that changes readings every 12.7 millimeters of fuel level change. From these fixed level points,
the ATS counts the number of liters of fuel used (based on load over time) and subtracts this from the
fixed-level fuel amount to give an accurate estimate of fuel level. The remaining runtime is then
calculated based on the fuel usage rate at the current load and the remaining fuel in the tank. Once a
new fuel level point is reached, the value of the calculated fuel used is reset and the computation
begins again.
The Fuel Level and Runtime Estimate are displayed on the Generator Status screen on the ATS
display interface, and you can set the following Fuel Alarm Limits in the Alarms menu of the
display interface:
Percent Fill: If the amount of fuel as a percentage falls below this value, an alarm condition
exists.
Runtime: If the estimated runtime falls below this value, an alarm condition exists.