# What is minimum clearance for a service of 240 volts above the roof?

## What is minimum clearance for a service of 240 volts above the roof?

8 feet
In general, overhead service conductors must maintain a minimum vertical clearance of 8 feet above the surface of a roof for a minimum distance of 3 feet in all directions from the edge of the roof [230.24(A)].

What is the minimum clearance from final grade for service drop conductors where the voltage does not exceed 150 volts to ground?

10 feet
10 feet above finished grade, sidewalks, or platforms/projections from which they might be accessible to pedestrians for 120/208V (or 120/240V circuits where the voltage doesn’t exceed 150V-to-ground).

### How much clearance must communication conductors have in a roof with a 4/12 Slope 4 inch rise and 12 inches horizontally )?

1] Where the roof has a slope of 4 inches (102 mm) in 12 inches (305 mm), or greater, the minimum clearance shall be 3 feet (914 mm).

What is the minimum clearance to a residential electrical service drip loop?

When the drip loop is over the ground, it must be a minimum of 10′-0” above the grade, which is the same minimum clearance as the rest of the service drop.

## What is the minimum size THWN conductor that can be used for a 100 A Service?

100 amps X 83% = 83 amps. This is the minimum required service conductor. Take 83 amps and use the 75°C column in Table 310.15(B)(16) to determine that the service requires 4 AWG copper, type THWN overhead service entrance conductors.

What size riser do I need for a 200 amp service?

Schedule 80 PVC plastic, EMT, or RIGID steel conduit service riser with 1 ½” minimum diameter for 100 or 150-amp service, 2″ minimum diameter for 200-amp service, or 2½” minimum diameter for 320-amp service.

### Does service entrance cable have to be in conduit?

You do not have to use conduit, you may use a service entrance cable of sufficient size. You may not run single wires without conduit. If you use conduit, I would recommend EMT.

Which is a reference to NEC Chapter 2?

Figure 230.1 graphically shows which parts of NEC Chapter 2 apply to the various parts of the power distribution system. This figure should be your “road map” to applying the requirements of NEC Chapter 2. Why is it a reference to Chapter 2, and not just Article 230?

## What are the NEC codes for direct buried conductors?

Where direct-buried conductors and cables emerge from the ground, they are required to be protected from physical damage by enclosures or raceways (schedule 80 PVC) that extend from the minimum cover distance (18 inches) to

What does 230.24 of the Electrical Code mean?

230.24 (very briefly) discusses clearances. “Overhead service conductors shall not be readily accessible….” (A) details the clearance above roofs, plus the exceptions. (B) details the clearance from ground, plus the exceptions.

### What does the NEC say about overcurrent devices?

For example, “no overcurrent device shall be inserted into a grounded service conductor except a circuit breaker that simultaneously opens all conductors of the circuit” [230.90 (B)]. The first four Chapters of the NEC apply to all installations.