Question 31
Which of the following is a common symptom of a loose neutral connection on a multi-wire branch circuit?
Question 32
In a multiwire branch circuit using a shared neutral, what is one important safety requirement?
Question 33
A 120/240 V single-phase panelboard serves a dwelling. Two 20 A single-pole breakers are used to supply a multi-wire branch circuit (MWBC) sharing a neutral. What is required for these breakers?
Question 34
During troubleshooting, an electrician finds a shared neutral (multi-wire branch circuit) feeding two 120 V circuits on the same phase. What is the main concern with this condition?
Question 35
A multiwire branch circuit shares a neutral between two hot conductors. To safely reduce neutral current and meet code, how should these ungrounded conductors be connected?
Question 36
On a commercial blueprint, multiple branch circuits serving office receptacles are marked with different circuit numbers but share the same neutral conductor in a multiwire branch circuit arrangement. What critical condition must be met for safety and code compliance?
Question 37
A grocery store has several refrigerated display cases fed from a panel located in a mechanical room. The manager reports that cases lose power whenever maintenance staff locks out one disconnect. You discover that several circuits share a common neutral. What design issue is most likely present?
Question 38
A multi-wire branch circuit (MWBC) shares a neutral between two ungrounded conductors on opposite phases. How should the breakers for the ungrounded conductors be arranged?
Question 39
On a multi-wire branch circuit feeding kitchen receptacles, an electrician observes lights dimming and brightening when appliances are switched on. What is a likely cause?
Question 40
A multi-wire branch circuit shares a neutral between two ungrounded conductors. Which condition is important to avoid overloading the neutral?
Question 41
A multiwire branch circuit (MWBC) serves two small-appliance circuits in a kitchen using a shared neutral. The breaker handle-tie has been removed, leaving two independent single-pole breakers on different phases. What is the PRIMARY safety concern with this condition?
Question 42
During an inspection of an older commercial building, you find that many neutrals and equipment grounding conductors are landed under the same terminal screw in a panelboard. What is the best corrective recommendation?
Question 43
A multi-wire branch circuit supplies two 120 V loads on opposite phases that are both drawing 10 A. Ignoring harmonics and imbalance, how much current flows in the shared neutral conductor?
Question 44
In a standard 120 V residential branch circuit in the US, which conductor color is typically used for the grounded (neutral) conductor?
Question 45
A large office building has multiple panelboards supplied from a main service. Nuisance tripping occurs on several 20 A, 120 V multi-wire branch circuits using shared neutrals. Which improvement best addresses objectionable neutral currents and harmonics from nonlinear loads?
Question 46
A multi-wire branch circuit supplies two small-appliance circuits in a kitchen. The shared neutral is loose in a junction box. What condition could this create at the receptacles?
Question 47
Which color is strictly reserved for the grounded conductor (neutral) in a branch circuit?
Question 48
For a 120V/240V 3-wire single-phase service, how is the neutral conductor typically sized relative to the ungrounded conductors?
Question 49
The 'neutral' conductor of a service drop is also known as the: