Breaker & Circuit Troubleshooting

A breaker is designed to protect the circuit. When it trips repeatedly, OTC wants to know what condition is making it trip before replacing anything.

Common causes can include:

• Circuit overload

• Short circuit

• Ground fault

• Failed breaker

• Damaged conductor

• Loose connection

• Water intrusion

• Equipment failure

• Improper breaker sizing

• Shared or incorrectly configured neutrals

Simply installing a larger breaker does not solve the problem and can create a much more serious electrical hazard.

The way a breaker trips can provide useful information.

A circuit that operates for a period of time and then trips may be experiencing an overload or equipment-related problem.

A breaker that trips immediately when energized may indicate a more direct fault somewhere downstream.

OTC isolates loads, tests the circuit, and works through the system to determine which condition actually exists.

Breakers can fail.

They may:

• Trip when they should not

• Refuse to reset

• Overheat

• Develop poor connections to the panel bus

• Become mechanically unreliable

• Fail to trip when they should

If the panel and bus remain in good condition, replacing a failed breaker may be all that is required.

If the breaker connection has already damaged the bus, the repair may become a panel replacement instead.

Many breaker trips are caused by something outside the panel.

OTC may trace the circuit through:

• Receptacles

• Junction boxes

• Equipment

• Exterior wiring

• Underground conductors

• Tenant modifications

to locate the actual failure.

This is especially important in older commercial buildings where circuits may have been extended or modified several times over the years.

OTC frequently sees general-purpose circuits overloaded by equipment such as:

• Microwaves

• Refrigerators

• Printers

• Copiers

• Space heaters

• Coffee equipment

• Appliances

• Specialty tenant equipment

The correct solution may be a dedicated circuit rather than continuing to reset the existing breaker.

Shared neutrals and multi-wire branch circuits can make troubleshooting more complicated.

If these circuits have been modified incorrectly, they can create:

• Unexpected voltage

• Backfeed conditions

• Nuisance trips

• Difficult circuit tracing

OTC verifies how the conductors are actually connected before assuming two breakers represent completely independent circuits.

Exterior and underground circuits frequently develop problems because of water.

OTC may find:

• Wet junction boxes

• Damaged underground conductors

• Failed splices

• Ground faults

• Deteriorated insulation

Where appropriate, insulation-resistance testing can help determine whether conductor insulation has been damaged.

Repeatedly resetting a breaker without identifying the cause is not a repair.

If the breaker continues to trip, it is telling you that something on the circuit needs attention.

OTC recommends troubleshooting the problem before repeated resets lead to:

• Heat damage

• Damaged conductors

• Damaged equipment

• Larger electrical repairs

Depending on the problem, OTC may:

1. Review what happened before the failure

2. Identify recent electrical or equipment changes

3. Inspect the breaker and panel

4. Remove or isolate connected loads

5. Test voltage and current

6. Trace the circuit

7. Inspect downstream wiring

8. Test equipment where appropriate

9. Repair the actual failure

10. Verify the circuit operates correctly before leaving

The goal is not to guess which part might be bad.

The goal is to prove where the problem is.