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AFCI-GFCI Circuit Breaker

Diagnostic Guide

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

Index

1. AFCI/GFCI circuit breaker diagnostic 3

1.1. Facts about arc faults 3

1.2. Facts about ground faults 3

3. Electrical professional diagnostic guide 8

3.1. Arc fault investigation 9

3.2. Arc fault diagnostic questions 10

3.3. Ground fault investigation 11

3.4. Ground fault diagnostic questions 11

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

Turn off the branch circuit breaker

Interrupter (AFCI) and Ground Fault Circuit Interrupter

(GFCI) circuit breakers.

The questions in this document are applicable to all branch

circuits fed by arc fault circuit interrupters (CAFCI or AFCI/GFCI)

or ground fault interrupters (GFCI or GFEP). This document is

to be used by Siemens application engineering, technical

support and sales teams, distributors, electrical contractors

and homeowners/end-users to provide application and

diagnostic feedback.

Guide, a qualified person is one who is familiar with the

installation, construction, and operation of the equipment,

and the hazards involved. In addition, he/she has the

following qualifications:

a) Is trained and authorized to energize, de-energize, clear,

ground and tag circuits and equipment in accordance with

established safety practices.

b) Is trained in proper care and use of protective equipment in

accordance with established safety practices.

c) Is trained in rendering first aid.

been protected by arc fault circuit interrupters circuit breakers.

An arc fault is a high-energy discharge created by current

flowing through an unwanted path. Generally, arc faults

are of short enough duration that they are not detected by

standard thermal magnetic circuit breakers. However, arc

faults can produce high-intensity heat – exceeding 10,000

degrees Fahrenheit – and can initiate fires. To mitigate fires

due to arc faults, AFCIs monitor the branch circuits and

mitigate the effects by de-energizing the circuits once an

arc-current signature is detected.

electrical shock, even in the low milliamps, flowing through a

body can cause injury or death.

The GFCI and GFEP circuit breakers work by comparing the

amount of current going to and returning from a branch

circuit. If the current differs by a defined value the GFCI or GFEP

circuit breaker will trip, thus shutting off power to the circuit.

Siemens offers Class A 5mA GFCI and 30mA GFEP circuit breakers

for their residential load centers. While the GFCI circuit breaker

provides personal protection from shock the GFEP circuit

breakers provides equipment protection from line-to-ground

breaker trips and the reason is unknown. The main sources of

nuisance tripping are wiring issues and incompatibility with

electronic devices. Wiring issues such as damaged wires, loose

connections, or incorrectly wired circuits are some examples

of conditions that can create nuisance trip events. To resolve

nuisance trip events associated with wiring issues the source

of the issue will need to be corrected. Incompatibility issues

can be created by loads that produce excessive noise that

eventually mimics an arc. It is recommended that all installed

electronic devices comply with CSA standard to avoid noisy

the specific circuit the circuit breaker is protecting, per the

load center circuit label (e.g. kitchen, bed room, living room,

lighting, etc.), and while the circuit break is in an ‘OFF’ state,

confirm that there are no obvious issues with the loads on

that circuit follow these steps:

1. Check for any blackened plugs or outlets. If found,

remove all plugs from the outlet and contact an

electrical contractor for further investigation.

a. Cords are pinched in doorways.

b. An appliance or furniture is pushed against electrical

plug or resting on a cord.

c. Cords deteriorated due to proximity to heat source

(e.g: heaters, hot air ducts, sunlight, etc.).

4. Ensure all bulbs are less than or equal to the maximum

wattage rating of the fixture. Higher rated bulbs can

cause excessive heat and damage.

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

6. Reset the circuit breaker by actuating its handle to the ‘OFF’

and then ‘ON’ position. If the circuit breaker trips again, a

a. Turn on and off each light individually, if lights are on

circuit, and observe if circuit breaker trips.

b. Plug in non-defective equipment one at a time, turn

on and off and observe if circuit breaker trips.

that caused a trip event from the circuit before reenergizing the circuit

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

Note: The 1 Pole Gen. 3B CAFCI circuit breaker does not offer ground fault protection.

2.2.2 1 pole Gen. 3B CAFCI circuit breaker trip-indicator LED lights:

2.2.4 2 pole Gen. 3B CAFCI circuit breaker trip-indicator LED lights:

Note: The 2 P Gen. 3 CAFCI circuit breaker does not offer ground fault protection.

2.2.3 2 pole Gen. 1 – 3A CAFCI circuit breaker trip-indicator LED lights:

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

Test

Button

2.2.7 1 pole Gen. 2 GFCI, 2 pole Gen. 1B GFCI, and 1 pole Gen. 2 GFEP

circuit breaker trip-indicator:

2.2.5 1 pole Gen. 1 – 1B AFCI (branch feeder) circuit breaker trip-indicator:

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

2.3 General diagnostic questions

1. *What type of circuit breaker is tripping?

2. *What are the date codes on the circuit breaker?

3. *What LEDs are lit on the circuit breaker after it tripped and is reset?

4. *What action/event caused the circuit breaker to trip? (For example: Turning on/off an appliance/device)

5. What is the load center circuit number and description?

9. Please specify property type – single family home/apartment complex/etc.

If other than single family home, how many units?

Please answer questions 1 through 8 per unit or provide common information such as all the kitchen breakers are tripping.

and reduce the number of visits required to solve the issue. Answers to the questions that are listed with red * are mandatory information needed to

understand the issue and escalate to an clectrical contractor.

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AFCI/GFCI Circuit Breakers | Diagnostic Guide AFCI/GFCI Circuit Breakers | Diagnostic Guide

3.1 Arc fault investigation

Follow the steps below to diagnose the root cause of a

via the ‘TEST’ button. Move handle to the ‘OFF’ and then ‘ON’

position. Reset has been completed, press the ‘TEST’ button

and observe the position of the circuit breaker’s handle. If

the breaker handle moves between the ‘OFF’ and ‘ON’

position, then the circuit breaker is working correctly. If the

circuit breaker does not trip, it needs to be replaced by an

electrical contractor. Observe and record the trip indicator

LED lights.

3. When checking for a loose light bulb, check that the line/hot

4. Check the wiring at the circuit breaker load terminal (line/

hot, load neutral, panel neutral/pig tail). Ensure the load

neutral conductor is properly connected to the neutral

terminal of the circuit breaker and the circuit breaker

neutral/pig tail is properly connected to the neutral bar. In

case you have a plug-on neutral AFCI or GFCI circuit breaker

you will not have a panel neutral/pig tail.

5. Check the wiring to ensure a single pole AFCI circuit breaker

lighting/appliances for loose connections. Siemens highly

recommends using screw connections for wire termination

on all outlets, switches, etc, instead of using the spring-

loaded ‘push-in’ connections. Ensure all screws and lugs

are tightened to specification.

7. Check the installed wiring for damaged insulation that may

expose hot wires to neutral or ground wires.

8. Check all devices for cUL and CSA compliance (LED lights,

9. If the arc-fault trip condition persists after all the wiring has

been verified follow these steps:

a. Disconnect all the loads on the circuit.

b. Energize each load individually until the AFCI circuit

breaker trips.

c. Move the latest energized load before the trip – where

possible – to another circuit to see if the trip condition

follows a specific device.