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Logixpro Dual Compressor Exercise 2 -

At 2:30, Maria Chen, the shift electrician, pulled up the LogixPro simulation on her laptop—the training software she’d mastered years ago. But this wasn’t a classroom exercise. This was Exercise 2 for real.

Maria’s fault wasn’t random. It was molten metal and fried bearings.

The plant floor at Apex Bottling was a cathedral of stainless steel and hydraulic hiss, but its heart was pneumatic. Two massive air compressors, Titan and Atlas, squatted in the corner, responsible for breathing life into the filling heads, capping machines, and labeling jets. If the air pressure dropped below 90 PSI, the entire line screeched to a halt. If it dropped below 80 PSI, safety interlocks would fire, locking the plant down entirely. logixpro dual compressor exercise 2

In LogixPro’s “Dual Compressor Exercise 2,” the goal was simple: maintain 90–100 PSI with two compressors, handle duty cycling, and prevent both from running simultaneously for too long to avoid overload. The twist? A random “fault” could disable one compressor, forcing the other to handle the load within strict time limits.

For the next forty minutes, Maria stood guard. Every 11 minutes, Atlas’s thermal overload would creep toward its limit. She’d manually cycle it off for 90 seconds—just long enough for the header tank’s stored volume to keep the line alive—then restart it. It was brutal, improvisational, and exactly like the simulation’s hardest setting: Manual Fault Recovery. At 2:30, Maria Chen, the shift electrician, pulled

In the LogixPro simulation, you had ladder logic timers: T4:0 for the “minimum run time” and T4:1 for the “anti-cycle delay.” Maria had no time to program. She had to become the PLC.

Maria’s mind flashed to the exercise rubric: “When a compressor faults, the alternate must take over within 2 seconds. Pressure must not fall below 80 PSI.” Maria’s fault wasn’t random

She sprinted to the MCC (Motor Control Center) and yanked the disconnect for Titan. The massive screw element ground to a halt with a mournful groan. The plant pressure gauge needle wobbled at 92 PSI and began to fall.

“Atlas, you’re up,” she whispered, hammering the HMI start button.

When the maintenance crew finally replaced Titan’s fan at 4:00 PM, Maria collapsed into a rolling chair. On the HMI, the pressure trend showed a near-perfect line at 88 PSI, with only one brief dip to 81.5 PSI.

She hit start again.