Determine the minimum current for conductors required to connect four motors in the same circuit. The first motor has a full-load current of 11 A; the second and the third motor have a full-load current of 26 A. The fourth motor has a full-load current of 16 A.

To determine the minimum current for conductors required to connect four motors in the same circuit, the approach is as follows:

1. **Sum the full-load currents**: 
   Add the full-load currents of all motors.
   - Motor 1: 11 A
   - Motor 2: 26 A
   - Motor 3: 26 A
   - Motor 4: 16 A

   \[
   \text{Total Full-Load Current} = 11\, \text{A} + 26\, \text{A} + 26\, \text{A} + 16\, \text{A} = 79\, \text{A}
   \]

2. **Apply the NEC (National Electrical Code) multiplier**: 
   According to the NEC, when multiple motors are connected in a circuit, the minimum current rating for the conductor is based on the sum of all motor currents, plus an additional 25% of the highest full-load current of any motor.

   The highest full-load current is 26 A (for Motor 2 or Motor 3). We calculate 25% of 26 A:

   \[
   25\% \times 26\, \text{A} = 6.5\, \text{A}
   \]

3. **Calculate the minimum current**:
   Add this 25% to the total full-load current:

   \[
   \text{Minimum Current} = 79\, \text{A} + 6.5\, \text{A} = 85.5\, \text{A}
   \]

Thus, the minimum current rating for the conductors required to connect the four motors is **85.5 A**.

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Would you like further details or have any questions?

Here are some related questions to expand on this:
1. How do different motor protection devices affect conductor sizing?
2. What is the NEC code reference for motor circuit conductors?
3. How do voltage drops impact the sizing of conductors in motor circuits?
4. How would you calculate the conductor size if the motors were three-phase?
5. How does ambient temperature affect conductor sizing for motor circuits?

**Tip**: When calculating motor circuit conductors, always account for the highest full-load current to ensure safety and compliance with electrical standards.

Find out how to determine the minimum current for conductors required to connect four motors in the same circuit. The motors have full-load currents of 11 A, 26 A, 26 A, and 16 A. Using the NEC (National Electrical Code) guidelines, this solution explains how to calculate the total current and the necessary 25% adjustment for the highest current motor, resulting in a total of 85.5 A.

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