How to Troubleshoot Obscure Electrical Problems in Older Commercial Buildings

Troubleshooting obscure electrical issues in older commercial buildings can be challenging, but following a systematic approach can help identify problems quickly and efficiently. Here is a comprehensive guide to troubleshooting electrical problems in older commercial spaces:

Gather Information on the Electrical System

Before trying to diagnose issues, gather as much information as possible about the electrical system in the building:

• Review electrical blueprints to understand how the system was originally wired and what changes may have occurred over time. Blueprints give you an overview of the circuits, panel locations, and device connections.

• Inspect the electrical panels and take notes on the circuit breakers/fuses, wire gauges, voltages, and how circuits are labeled. This provides insights into the panel's overall condition and capacity.

• Interview building maintenance staff to learn about any past electrical issues, repairs, or system modifications. Long-time employees often have invaluable institutional knowledge.

• Document equipment nameplate data for motors, appliances, HVAC units, etc. This gives you their electrical load details to help trace circuits.

Thorough background research sets the foundation to systematically diagnose obscure problems.

Check for Basic Faults First

Before getting into complex troubleshooting, rule out some of the most common electrical faults:

• Check for tripped breakers or blown fuses in the panels and reset or replace any found. Frequently cycling breakers/fuses indicate an overload or short circuit.

• Inspect all switches, receptacles, junction boxes, etc. for loose, damaged, or corroded connections that may be causing resistance and heat buildup. Tighten or replace defective devices.

• Check that circuit neutral and ground wires are securely bonded. Loose neutrals can cause intermittent contacts.

• Verify proper voltage and phase rotation for three-phase circuits. Simple voltage issues can cause erratic motor behavior.

• Perform insulation resistance tests to check for leakage or deteriorating insulation in wiring or devices.

Fixing obvious faults first prevents wasting time chasing complex hypothetical issues.

Isolate Affected Circuits

Localizing electrical problems to specific circuits helps deduce root causes:

• Correlate past outage history with circuit maps to identify chronic problem circuits. Focus troubleshooting on those first.

• Categorize issues (outages, flickering lights, tripped breakers, etc.) and match them to circuits experiencing the same symptoms.

• Disconnect suspected circuits at panels and operate them on a temporary feed. This often pinpoints faults to specific circuit sections.

• Check voltages and continuity section-by-section to follow faults along a circuit's path. Voltage drops or open circuits reveal issues.

• Inspect all junction points on suspect circuits for loose or corroded connections impeding current flow.

Methodically isolating the malfunctioning circuit brings you closer to the root cause. Don't waste time troubleshooting properly operating circuits.

Use Clamp Meters to Measure Loads

Clamp meters are invaluable tools for tracking down electrical issues:

• Check individual cable loads against rated ampacities to identify potential overloads causing intermittent faults.

• Measure circuit load changes over time to detect increasing consumption signalling a developing short circuit or motor issue.

• Compare phase loads on three-phase circuits. Imbalances can lead to motor problems or insulation breakdown.

• Correlate loads with equipment operation to associate specific devices with observed electrical anomalies.

• Check seemingly dead circuits for phantom loads indicating a downstream short circuit is still consuming current.

Clamp meter measurements provide vital data for isolating the source of problems. Become very familiar with using them.

Consider Power Quality Issues

"Dirty power" can produce electrical faults resembling equipment or wiring failures:

• Check for voltage fluctuations or dropouts with logging meters. Transient dips can disrupt sensitive electronics or trigger breaker nuisance tripping.

• Scan for harmonic distortion. High frequency harmonics overheat neutral wires and damage electronics.

• Test for electrical noise interference. EMI/RFI noise can disrupt control signals or data networks.

• Detect significant phase imbalance on three-phase feeds. Imbalance strains motors leading to overheating failures.

• Inspect for corroded or oxidized connections. Resistive corrosion causes heat buildup at connections.

Pay close attention to power quality and don't assume consistent "clean" power. Install monitors permanently at suspect panels.

Seek Specialist Support for Complex Issues

For lingering complex electrical gremlins, don't hesitate to enlist specialized technical support:

• Work with an electrical engineer to perform detailed forensic analysis of system issues, especially for large or intricate systems.

• Hire thermographic imaging contractors to scan for hidden connection hot spots or overheated equipment.

• Engage motor repair specialists for diagnosis of motor winding or mechanical problems.

• Consult power quality experts to fully characterize electrical noise, harmonics, or transient anomalies.

At some point your tools and knowledge may not be sufficient - know when to call in the experts rather than spin your wheels.

Properly troubleshooting obscure electrical issues requires methodically gathering data, isolating problems, taking measurements, and being ready to call in speciality expertise when needed. Following these guidelines will lead you to the root cause much faster in those difficult older buildings. Patience and persistence ultimately pays off.