Common Pitfalls in New Systems: How to Avoid Early Failures

"All men are liable to error;"

—John Locke

While seasoned systems tend to fail from wear and tear, brand‑new installations often crash because of human error in design or assembly. This section examines the most frequent early‑life failures and offers practical prevention tips.

Wiring Problems

Incorrect connections, caused by assembly mistakes or sub‑standard connectors, are the leading cause of early wiring failures. Short circuits frequently result from accidental bonding of conductors to grounding points or from wires being pinched beneath cover plates.

Another subtle issue is electromagnetic interference that creeps in when signal cables are routed too close to power conductors. Identifying such proximity‑induced noise with test equipment can be challenging, so proper cable separation during design is essential.

Power Supply Problems

Blown fuses or tripped breakers are often the first symptoms, especially when a new system is added to an existing installation. Over‑loading can occur if the anticipated load is underestimated, causing the supply to trip or, worse, to fail permanently.

Defective Components

In freshly assembled systems, the likelihood that a component is faulty "out of the box" is roughly equal for all types—whether active or passive—unless the component is particularly sensitive to transport (e.g., vacuum tubes, electrostatic‑sensitive semiconductors). These defects are not always obvious by visual inspection, so rigorous testing during commissioning is vital.

Improper System Configuration

With the rise of microprocessor‑based controls, configuration errors now extend beyond simple hardware settings. Incorrect time‑delay relay settings, miscalibrated limit switches, or improperly set jumpers can cripple a system. In larger setups, even small errors in power‑rating selection—such as installing a low‑power resistor—can lead to overheating and failure.

Design Error

Design errors are often the most insidious. They surface only when the system is pushed beyond its intended operating envelope, and they can be overlooked because the design is assumed to be sound. A classic example is a turbine control system that used an oil‑pressure switch to shut the turbine down when oil pressure fell. Because the oil pump is driven by the turbine itself, a fresh start cannot raise oil pressure, causing the system to lock out immediately. Correcting such a flaw requires a fundamental change in the logic, not a simple component replacement.

Some design flaws remain hidden until very specific conditions arise—such as an emergency coolant circuit that never activates during normal operation. These “latent” faults are especially dangerous because they can go unnoticed until a catastrophic event occurs.

RELATED WORKSHEETS:

• Basic Troubleshooting Strategies Worksheet
• Basic Circuit Troubleshooting Worksheet