Electrical systems in older commercial buildings can develop unusual faults over time that may be difficult to diagnose. As the building electrician, it is my job to methodically troubleshoot these issues to restore power and prevent safety hazards. In this article, I will share my approach for tracking down tricky electrical gremlins in aging electrical infrastructure.
Understanding Common Electrical Issues in Old Buildings
Older commercial buildings often use outdated electrical systems that were installed decades ago per older electrical codes. Common electrical issues include:
-
Frequent circuit breaker tripping - Outdated breaker panels may not handle modern power loads. Short circuits or ground faults can also trip breakers.
-
Flickering lights - This indicates a loose neutral wire connection. Vibration over time can loosen wiring connections.
-
Equipment malfunctions - Motors, HVAC systems, and appliances may malfunction due to unstable voltage or frequency from a faulty power source.
-
Corroded connections - Heat, moisture and corrosion can degrade connection points leading to high resistance faults.
-
Rodent damage - Mice or rats may chew through wire insulation causing dangerous shorts.
-
Overloaded circuits - Outdated circuits may not support added loads from new equipment and devices.
Knowing these common issues will help me diagnose unusual electrical faults explained in the following sections.
Conducting a Thorough Electrical Inspection
My first step is always to thoroughly inspect the building's electrical system:
-
Check the utility service entrance and meter for damage. Signs of corrosion, heat stress or physical damage can indicate issues with the supply power.
-
Inspect the main distribution panel and all subpanels, looking for corrosion, cracked insulation, signs of arcing/burning or heat damage.
-
Remove each circuit breaker cover and inspect for loose, broken or corroded connections. Test operation of each breaker.
-
Follow each circuit by its conduit or wiring through the building, checking condition and connections.
-
Identify all connected equipment and receptacles. Check for damage, signs of overheating and other anomalies.
-
Use a multimeter to check voltage, frequency, and current draw on all circuits and connected devices while operating.
-
Carefully inspect all conduit connections, junction boxes and visible wiring for damage. Vibration can degrade connections over time.
-
Check for evidence of rodent damage. Look for droppings, chewed insulation or nesting materials.
Thoroughly inspecting the electrical system provides clues to locate faults causing unusual issues. I make detailed notes and take photos to document anomalies.
Using Diagnostic Tools to Pinpoint Problems
Visual inspection provides the first clues to unusual electrical issues. To further isolate problems, I use diagnostic tools:
-
A digital multimeter checks voltage, resistance, continuity, frequency, amps - critical data for troubleshooting.
-
A clamp meter measures current flow through cables without breaking connections. Useful for detecting overload faults.
-
A megohmmeter tests insulation resistance between conductors and ground. Low values indicate insulation breakdown.
-
Socket testers check outlets for proper wiring, grounding, polarity and GFCI function.
-
A fuse puller tool helps safely remove and test fuses.
-
An infrared camera detects hot spots from high resistance connections and overloads.
-
A circuit breaker finder identifies which breaker corresponds to each circuit.
Methodically using these diagnostic tools provides vital data to pinpoint faults causing unusual electrical issues. I isolate problems down to specific circuits or devices.
Systematic Troubleshooting for Unusual Electrical Faults
With inspection findings and diagnostic data, I follow a systematic process to zone in on unusual electrical gremlins:
1. Correlate findings to electrical issues
-
Match up noted anomalies with electrical problems to identify probable fault locations.
-
Assess which findings are directly related versus coincidental.
2. Isolate affected circuit(s)
-
Use circuit breaker finders and wiring diagrams to identify affected circuits.
-
Inspect/test components only on suspect circuit(s) to limit possibilities.
3. Divide circuit into segments
-
Mentally divide circuit into sections using junction boxes and branches.
-
Test each segment individually to pinpoint fault location.
4. Replace components selectively
-
Replace inexpensive parts like contacts and fuses in suspect segments first.
-
Only replace expensive parts if testing conclusively indicates failure.
5. Verify proper operation
-
After repairs, thoroughly retest repaired circuit segments.
-
Operate connected equipment to confirm normal function.
-
Retest previously affected circuits - fixing one fault may reveal others.
This systematic process narrows down unusual faults and prevents replacing good parts. I focus repair efforts only where testing and inspection data points.
Gaining Experience Identifying Obscure Electrical Anomalies
Finding and fixing unusual electrical issues in old buildings involves detective work. Every case provides learning experiences identifying obscure anomalies like:
-
A fan motor malfunction caused by radio frequency interference from a rooftop antenna.
-
Burned out igniter on a HVAC unit from voltage spikes on the circuit.
-
Corroded ground rod causing stray voltages on metallic equipment like ducting and railings.
-
Rodent nest inside a wall chewed through wires shorting hot to neutral.
These examples illustrate the value of inspecting the entire system, looking for patterns and correlating findings across circuits. Experience gives me an intuitive sense where to search for elusive electrical gremlins.
In summary, methodically troubleshooting unusual electrical faults requires thoughtful inspection, diagnostic testing and correlating findings across the entire system. Isolating problems to specific circuits or components avoids unnecessary repairs. Experience and intuition also play a key role identifying obscure anomalies. Using this approach, I can solve difficult electrical faults and maintain safe, reliable power in aging commercial buildings.