Okay, Becca, I've reviewed the provided drawing and your initial concerns. Here's a breakdown of my findings, confirming some of your suspicions and highlighting other areas to review

Link to Drawing:

[https://drive.google.com/file/d/1-p956V1vN0hH6v9n8OQ2x1F7L-I8z-Xb/view?usp=sharing](https://drive.google.com/file/d/1-p956V1vN0hH6v9n8OQ2x1F7L-I8z-Xb/view?usp=sharing)NEC Code References (2020 NEC unless otherwise specified)

I'll try to give as many NEC references as possible without getting too bogged down. Keep in mind that exact code interpretations can vary by jurisdiction and inspector. This is intended as a good starting point for review.

1. Grounding Conductor (EGC PUMP)



Your Suspicion: CORRECT. This is undersized. Analysis

The 10 HP motor is supplied by a 20A breaker. NEC 250.122 dictates the minimum size of equipment grounding conductors based on the size of the overcurrent protective device. For a 20A overcurrent device, Table 250.122 requires a minimum of a #12 AWG copper EGC. The drawing specifies a #14 AWG, which is too small.

Recommendation

The EGC for the pump motor must be upgraded to at least #12 AWG copper (or equivalent size in aluminum, as permitted by 250.122).

2. Pump Starter Size



Your Suspicion: CORRECT. Likely should be a NEMA Size 1, not 2. Analysis

We need to determine the full-load amps (FLA) of the 10 HP, 460V motor. Table 430.250 (Full-Load Current, Three-Phase Alternating-Current Motors) indicates an FLA of 14 amps for a 10 HP, 460V motor. NEMA starter sizes are based on horsepower and current ratings. A NEMA Size 1 starter typically handles motors up to 10 HP @ 460V. A Size 2 is often used for larger motors. While a Size 2 starter will work (oversizing is generally permissible), it's likely more expensive than necessary. The proper overload relays should be chosen regardless of the starter size.

Recommendation

Verify the starter manufacturer's specifications for the motor horsepower and current range. A NEMA Size 1 starter is likely sufficient and more economical. Be sure to select the correct overload relay heaters/settings based on the motor FLA (14 amps).

3. Control Wiring Size



Your Suspicion: Possibly Oversized. Analysis

The drawing specifies #14 AWG for the control wiring. We need to calculate the current in the control circuit. You mention 850 Watts. Assuming 120V, the current is 850W / 120V = ~7.08 amps. #14 AWG copper is typically rated for 15 amps. NEC 430.72 (Motor Control Circuit Conductors) generally permits using smaller conductors in control circuits, provided certain conditions are met (e.g., overcurrent protection, type of enclosure, etc.).

If the control circuit conductors are protected at their ampacity (15A for #14), then the sizing is permissible. If this is the intention, this should be noted in the drawings. Recommendation

Confirm the voltage of the control circuit (120V assumed). Verify that the control circuit conductors are appropriately protected by an overcurrent device no larger than the ampacity of the wire.

Consider using #16 or #18 AWG, provided the conditions of 430.72 are met, this could save cost on wiring. Check the specifications of the control components to make sure the terminations will accept the conductor size being used.4. HID Pump Lighting



Continuous Load

You mentioned this is a continuous load. This has implications for the required circuit ampacity and overcurrent protection.

NEC 210.19(A)(1) and 210.20(A)

For continuous loads (defined as operating for 3 hours or more), the branch circuit conductors and overcurrent devices must be rated for at least 125% of the continuous load current.

Action

Determine the total wattage of the HID lighting load. Calculate the current at 460V (assuming that's the voltage). Multiply that current by 1.25 to determine the minimum required ampacity of the conductors and the minimum rating of the overcurrent device.

Example

If the HID lighting is 1000 Watts, the current is 1000W / 460V = ~2.17 amps. 1.25 x 2.17 = ~2.71 amps. This means the conductors and breaker must be rated for at least 2.71 amps.

Review

Make sure the breaker size and conductor size meet the 125% rule for continuous loads for the HID pump lighting.

5. Overcurrent Protection (Breaker Sizes)



Motor Branch Circuit

The 20A breaker for the 10 HP motor needs careful review to ensure it complies with NEC 430.52. NEC 430.52 allows for instantaneous trip circuit breakers (inverse time breakers are not allowed) to protect motor circuits, with settings up to 800% of the motor's FLA (for certain motor types). The 20A breaker seems low to me since the motor FLA is 14amps.

Recommendation

Determine the type of overcurrent device used. A standard inverse time breaker will likely trip upon motor starting. Consult Table 430.52 to determine the maximum allowable size or setting of the overcurrent protective device, based on the motor type and protective device type. This is a critical safety issue and should be thoroughly checked.

Action

Double-check that the overcurrent device is sized appropriately based on NEC 430.52, considering the motor code letter and type of protective device.

HID Lighting Branch Circuit

The breaker size must comply with the continuous load requirements outlined in point #4.

6. Wire Types and Ampacities

Verify that the conductor types used (THHN, etc.) are suitable for the application and environment. Ensure that the ampacities of the conductors are appropriate for the termination temperature ratings of the connected equipment (NEC 110.14(C)). Often, you'll need to use the 75°C column of Table 310.16 for ampacity derating. Confirm the proper derating factors are applied if conductors are bundled or run in conduit with multiple circuits (NEC 310.15).

7. Conduit Fill

Verify that the conduit fill percentage does not exceed the allowable limits specified in Chapter 9 of the NEC.

8. Disconnect Switch

Ensure that the disconnect switch (both for the motor and the HID lighting) is properly rated for the voltage and current. A horsepower-rated disconnect is required for the motor (NEC 430.109). Check that the disconnects are readily accessible (NEC 430.107).

9. Short-Circuit Current Rating (SCCR)

This is a very important aspect of electrical design that is often overlooked.

NEC 110.10

Requires that equipment be rated to withstand the available fault current at its terminals.

Action

Calculate or obtain the available fault current at the location of the motor starter and the HID lighting panel. Verify that the SCCR of the starter, panel, and all other components is greater than the available fault current. If not, you may need to use series-rated components or other methods to increase the SCCR.

In Summary



Definite Need for Correction

The EGC for the pump motor is undersized.

Likely Correction Needed

The pump starter is probably oversized.

Needs Further Review

The overcurrent protection (breaker sizes) for both the motor and HID lighting needs careful examination to comply with NEC 430.52 and continuous load requirements. The control wiring may be able to be downsized, check that it is protected to the ampacity.

Important Considerations

Review SCCR, conductor ampacities, conduit fill, and disconnect switch ratings.

Verify any local code amendments or requirements, as they may be more stringent than the NEC.

This is a good starting point for your review. Take each of these points, research the relevant NEC sections, and double-check the calculations and component specifications. Good luck! Flag for review