elec. requirements for generator @ house ?

[chris rose]

I have an existing overhead electrical service but iam interested in using a back up generator for power outages do i need a special (transfer switch) switch or disconnect. And can i connect a cord to the switch for the removal of the generator.

 

[iwire]

You are required to use some type of transfer equipment listed for the purpose.

Take look at all of Article 702.

 

[bphgravity]

Here is some additional guidance:

When installing generators to be connected to household electrical service, obtain proper Building Department permits and hire professionals
State officials are encouraging Floridians to depend more on their own resources should a hurricane strike. Hearing that message, many have begun purchasing generators and transfer switches that allow those generators to be connected directly to the household electrical service panel.
If you are planning on having such a system installed, you must first apply for a permit from the North Port Building Department, and the work must be inspected by the City upon completion.
Because installing a generator is very complicated, the Building Department strongly recommends that a licensed and insured electrical contractor and qualified generator installer be hired to do the job.
If you are planning on installing a generator to be connected directly to your home’s electrical service, refer your installer and/or electrical contractor to the following North Port Building Department guidelines.
Please don’t hesitate to contact the Building Department at 423-3186 if you have any questions.
Application Permit Requirements
A standard City of North Port permit application for installing a generator connected to a home’s electrical service costs $40.00, plus any applicable surcharges. Documents required at time of application include:
1. A site plan showing the generator’s location;
2. The location of the generator’s fuel source and the type of fuel to be used;
3. Manufacturer’s specifications;
4. An itemized list of the electrical loads to be served, including any motor loads using motor startup current;
5. Diagrams of feeders, including the size and type of conductors to be used.
Contact Florida Power and Light before installation
If it is necessary for the electrical service to be turned off, or if access is required inside the meter enclosure, the homeowner or installer must contact to arrange for disconnection of the electrical service. The toll-free telephone number for FPL is 1-800-226-3545.
After the installation
After installation, contact the North Port Building Department at 423-3186 for the required final inspection of the work. PLEASE NOTE that the City must approve the work before FPL will restore power to the premises.
Guidelines for Portable Generators with Manual Transfer Equipment:
Permanently installed equipment for the connection of a portable generator must comply with Section 702.6 of the 2002 National Electrical Code (NEC). The manual transfer equipment will require an interlock device suitable for the intended use. This device must be installed to prevent the inadvertent interconnection of the normal and the optional system supply. The connection device must be a UL Standard 231 Listed Power Outlet. The back-feeding of electrical outlets within the home is not permitted.
Guidelines for Permanent Generators with Manual Transfer Switches:
Permanently installed generators with permanently installed manual transfer equipment must comply with the provisions for portable generators or use a Listed Transfer Switch or Panel Board. The equipment must be installed so as to allow the user to select the connected loads upon manual transfer.
Guidelines for Permanent Generators with Automatic Transfer Equipment:
Permanently installed generators with automatic transfer equipment must comply with the provisions of Section 702.5 of the 2002 National Electrical Code. The calculated load as determined by Article 220 of the 2002 NEC must not exceed the rating of the generator output. Please note that a “Demand Load” will not be accepted in lieu of the calculated load.
ALL load calculations must be included with the approved permit documents and must be available on site with the permit placard at the time of the inspection. All transfer equipment must be listed. Automatic transfer equipment installed on the supply side of the method of disconnecting the service must be listed as suitable for use as service equipment.
Required permanent signs for all installations
Permanent signs must be posted at all of the above-described installations that comply with Section 702.8 of the 2002 National Electrical Code. The required signs must indicate the type and location of the on-site optional standby power source, and must be permanently installed and located at the service disconnection point and at the meter enclosure.
All equipment must be installed according to the manufacturer’s instructions.
Portable generators with built-in power receptacles
Generators that supply power to connected equipment through built-in receptacles mounted on the generator DO NOT REQUIRE PERMITS OR INSPECTIONS.
However, they must be placed well away from a home or any air intake to prevent the danger of carbon monoxide poisoning.
As with any of the equipment listed above, be sure to read and follow all safety precautions in your user’s manual.

 

[iwire]

A standard City of North Port permit application for installing a generator connected to a home?s electrical service costs $40.00, plus any applicable surcharges. Documents required at time of application include:
1. A site plan showing the generator?s location;
2. The location of the generator?s fuel source and the type of fuel to be used;
3. Manufacturer?s specifications;
4. An itemized list of the electrical loads to be served, including any motor loads using motor startup current;
5. Diagrams of feeders, including the size and type of conductors to be used.
Contact Florida Power and Light before installation

Tough area, here I would probably just tell them the KW so they could determine the cost of the permit.

Here is what I would have to fill out.

Massachusetts Uniform Electrical Permit Application pdf

 

[chris kennedy]

Bryan, is that based on Tarry Baker's policy #06-01? Doug has been looking for that and I can't access that through Browards website. I remember you saying you had that. I have hard copy only. Any chance of posting up?

 

[bphgravity]

I actually wrote ours before I received Mr Baker's, but they are both based on the same principle:

Here is the first half:

Permanent Installed Residential Optional Stand-By Systems
in accordance with 2002 National Electrical Code


I. Article 702 Optional Stand-By Systems

702.1 Scope.
The provisions of this article apply to the installation and operation of optional standby systems.
The systems covered by this article consist of those that are permanently installed in their entirety, including prime movers, and those that are arranged for a connection to a premises wiring system from a portable alternate power supply.

The scope of Article 702 was revised for the 2002 NEC to clarify that it applies not only to permanently installed generators and prime movers, but also to portable alternate power supplies that can be connected to an optional standby system. For example, upon failure of an optional standby generator at a frozen food processing plant, a vehicle-mounted generator can be brought in and connected to the plant's optional standby system, which has provisions for such a connection.
Optional standby systems are those in which failure can cause physical discomfort, serious interruption of an industrial process, damage to process equipment, or disruption of business.

702.2 Definition.
Optional Standby Systems. Those systems intended to protect public or private facilities or property where life safety does not depend on the performance of the system. Optional standby systems are intended to supply on-site generated power to selected loads either automatically or manually.
FPN: Optional standby systems are typically installed to provide an alternate source of electric power for such facilities as industrial and commercial buildings, farms, and residences and to serve loads such as heating and refrigeration systems, data processing and communications systems, and industrial processes that, when stopped during any power outage, could cause discomfort, serious interruption of the process, damage to the product or process, or the like.

702.3 Application of Other Articles.
Except as modified by this article, all applicable articles of this Code shall apply.

702.5 Capacity and Rating.
An optional standby system shall have adequate capacity and rating for the supply of all equipment intended to be operated at one time. Optional standby system equipment shall be suitable for the maximum available fault current at its terminals. The user of the optional standby system shall be permitted to select the load connected to the system.


II. Optional Calculations for Computing Feeder and Service Loads

220.30 Optional Calculation — Dwelling Unit.

(A) Feeder and Service Load. For a dwelling unit having the total connected load served by a single 3-wire, 120/240-volt or 208Y/120-volt set of service or feeder conductors with an ampacity of 100 or greater, it shall be permissible to compute the feeder and service loads in accordance with this section instead of the method specified in Part II of this article. The calculated load shall be the result of adding the loads from 220.30(B) and (C). Feeder and service-entrance conductors whose demand load is determined by this optional calculation shall be permitted to have the neutral load determined by 220.22.




(B) General Loads. The general calculated load shall be not less than 100 percent of the first 10 kVA plus 40 percent of the remainder of the following loads:

(1) 1500 volt-amperes for each 2-wire, 20-ampere small-appliance branch circuit and each laundry branch circuit specified in 220.16.
(2) 33 volt-amperes/m2 or 3 volt-amperes/ft2 for general lighting and general-use receptacles. The floor area for each floor shall be computed from the outside dimensions of the dwelling unit. The computed floor area shall not include open porches, garages, or unused or unfinished spaces not adaptable for future use.
(3) The nameplate rating of all appliances that are fastened in place, permanently connected, or located to be on a specific circuit, ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and water heaters.
(4) The nameplate ampere or kVA rating of all motors and of all low-power-factor loads.

(C) Heating and Air-Conditioning Load. The largest of the following six selections (load in kVA) shall be included:

(1) 100 percent of the nameplate rating(s) of the air conditioning and cooling.
(2) 100 percent of the nameplate ratings of the heat pump compressors and supplemental heating unless the controller prevents the compressor and supplemental heating from operating at the same time.
(3) 100 percent of the nameplate ratings of electric thermal storage and other heating systems where the usual load is expected to be continuous at the full nameplate value. Systems qualifying under this selection shall not be calculated under any other selection in 220.30(C).
(4) 65 percent of the nameplate rating(s) of the central electric space heating, including integral supplemental heating in heat pumps where the controller prevents the compressor and supplemental heating from operating at the same time.
(5) 65 percent of the nameplate rating(s) of electric space heating if less than four separately controlled units.
(6) 40 percent of the nameplate rating(s) of electric space heating if four or more separately controlled units.

220.31 Optional Calculations for Additional Loads in an Existing Dwelling Unit.
This section shall be permitted to be used to determine if the existing service or feeder is of sufficient capacity to serve additional loads. Where the dwelling unit is served by a 120/240-volt or 208Y/120-volt, 3-wire service, it shall be permissible to compute the total load in accordance with 220.31(A) or (B).

(A) Where Additional Air-Conditioning Equipment or Electric Space-Heating Equipment Is Not to Be Installed. The following formula shall be used for existing and additional new loads.

Load (kVa) Percent of Load
First 8 kVA of load at 100
Remainder of load at 40

Load calculations shall include the following:

(1) General lighting and general-use receptacles at 33 volt-amperes/m2 or 3 volt-amperes/ft2 as determined by 220.3(A)
(2) 1500 volt-amperes for each 2-wire, 20-ampere small-appliance branch circuit and each laundry branch circuit specified in 220.16
(3) Household range(s), wall-mounted oven(s), and counter-mounted cooking unit(s)
(4) All other appliances that are permanently connected, fastened in place, or connected to a dedicated circuit, at nameplate rating


(B) Where Additional Air-Conditioning Equipment or Electric Space-Heating Equipment Is to Be Installed. The following formula shall be used for existing and additional new loads. The larger connected load of air-conditioning or space-heating, but not both, shall be used.

Air-conditioning equipment 100
Central electric space heating 100
Less than four separately controlled space-heating units 100
First 8 kVA of all other loads 100
Remainder of all other loads 40

Other loads shall include the following:
(1) General lighting and general-use receptacles at 33 volt-amperes/m2 or 3 volt-amperes/ft2 as determined by 220.3(A)
(2) 1500 volt-amperes for each 2-wire, 20-ampere small-appliance branch circuit and each laundry branch circuit specified in 220.16
(3) Household range(s), wall-mounted oven(s), and counter-mounted cooking unit(s)
(4) All other appliances that are permanently connected, fastened in place, or connected to a dedicated circuit, including four or more separately controlled space-heating units, at nameplate rating

 

[bphgravity]

Here is the second half - same document:

220.35 Optional Calculations for Determining Existing Loads.
The calculation of a feeder or service load for existing installations shall be permitted to use actual maximum demand to determine the existing load under the following conditions:

(1) The maximum demand data is available for a 1-year period.

Exception: If the maximum demand data for a 1-year period is not available, the calculated load shall be permitted to be based on the maximum demand (measure of average power demand over a 15-minute period) continuously recorded over a minimum 30-day period using a recording ammeter or power meter connected to the highest loaded phase of the feeder or service, based on the initial loading at the start of the recording. The recording shall reflect the maximum demand of the feeder or service by being taken when the building or space is occupied and shall include by measurement or calculation the larger of the heating or cooling equipment load, and other loads that may be periodic in nature due to seasonal or similar conditions.
(2) The maximum demand at 125 percent plus the new load does not exceed the ampacity of the feeder or rating of the service.
(3) The feeder has overcurrent protection in accordance with 240.4, and the service has overload protection in accordance with 230.90.















Electrical Riser Diagram:
Provide electrical riser diagram. These plans shall indicate the service, panel(s), transfer switch(s), main disconnect(s), generator installation, overcurrent protection, grounding , conduit sizes and wire sizes.

Generator:

1. Provide load calculations for the generator. NEC Article 220 (See Above) shall be used to calculate existing loads. Where the generator is connected to the load through a cord-and-plug (Exposed metal parts shall be non-current carrying.), the receptacle shall be sized for the corresponding overcurrent protection at the generator or other overcurrent protection device in front of the receptacle.
2. Generator shall be sized for the load served. NEC Article 220 (See Above) shall be used to calculate the existing load.

Transfer Switch: Required for all generators shall be rated for the connected load.

Manual Transfer Switch: (Options)

1. Sized for the intended load on the electrical service or
2. Sized for optional standby panel(s) which may be built into the panel(s) and transfer switch(s).

Automatic Transfer Switch: (Options)

1. Size to transfer the entire load on the electrical service or
2. Pre-select the loads to be served with an optional standby panel(s) and transfer switch(s) or
3. Provide Automatic load shedding equipment to reduce total load imposed on generator.

Sign:
A. A permanent sign shall be placed at the electrical service entrance equipment that indicates the location of on-site optional standby power sources.
B. A permanent sign shall be placed at the transfer switch location indicating the sequence of operation to start the generator and to transfer the electrical loads.

Other Requirements Non-Electrical

Site Plan:
Indicate generator and fuel tank locations.
Indicate location of all operable windows and operable doors near generator exhaust (Generator spacing from the building shall meet manufacturer’s specifications from all openings and operable doors, including those in the neighbors house). The location of the generator shall conform to local zoning requirements and shall be mounted above the base flood level. Provide dbA sound ratings if required per local ordinance. Additional permits for Mechanical, Plumbing and Structural may be required.

Slab Drawing:
Provide applicable structural plans. These plans shall indicate, as a minimum:
A. Provide the size and depth of the slab and type of reinforcement use
B. Provide generator anchoring details.






The optional method described in Section 220.31(A) or (B) allows an additional load to be supplied by an existing service.

Example

An existing dwelling unit is served by a 100-ampere service. An additional load of a single 5 kVA, 240-volt air conditioning unit is to be installed. Because the exiting load does not contain heating or air-conditioning equipment, the existing load is calculated according to 220.31(A). The load of the existing dwelling unit consists of the following:

General lighting, 24 ft ? 40 ft = 960 ft2 ? 3 VA per ft2 2,880 VA
Small-appliance circuits (3 ? 1500 VA) 4,500 VA
Laundry circuit at 1500 VA 1,500 VA
Electric range rated 10.5 kW 10,500 VA
Electric water heater rated 3.0 kW 3,000 VA
Total existing load 22,380 VA

Step 1.
Following the requirements of 220.31(A), calculate the existing dwelling unit load before adding any equipment:

First 8 kVA of load at 100% 8,000 VA
Remainder of load at 40% (22,380 – 8,000) = 14,380 ? 40% 5,752 VA
Total load (without air-conditioning equipment) 13,752 VA
13,752 VA ? 240 V 57.3 amps

Step 2.
Prepare a list of the existing and new loads of the dwelling unit.

General lighting, 24 ft ? 40 ft = 960 ft2 ? 3 VA per ft2 2,880 VA
Small-appliance circuits (3 ? 1500 VA) 4,500 VA
Laundry circuit at 1500 VA 1,500 VA
Electric range rated 10.5 kW 10,500 VA
Electric water heater rated 3.0 kW 3,000 VA
Added air-conditioning equipment 5,000 VA
Total new load 27,380 VA

Step 3.
Following the requirements of 220.31(B), calculate the dwelling unit total load after adding any new equipment.

First 8 kVA of other load at 100% 8,000 VA
Remainder of other load at 40% (22,380 – 8,000) = 14,380 ? 40% 5,752 VA
100% of air-conditioning equipment 5,000 VA
Total load (with added air-conditioning equipment) 18,752 VA
18,752 VA ? 240 V 78.13 amps

The additional load contributed by the added 5-kVA air conditioning does not exceed the allowable load permitted on a 100-ampere service.

 

[iwire]

A site plan so I can install a simple residential generator?

I am so glad I work here.

The power company would not be involved in it either.

 

[bphgravity]

It may seem a little overbearing, however, the state of Florida has had a huge problem with generator installations over the last few years. (huricanes of 2004 and 2005)

Tarry Baker sat on Panel 13 during this period and also served as a consultant to the Florida Building Commission on this matter. As a prominent member of the IAEI and as chief electrical code compliance officer for the Broward County Board of Rules and Appeals, Tarry commands a great amount of respect by the electrical community here in Florida.

Plus he is a really nice guy and a grreat friend!

 

[chris kennedy]

Thank you Bryan, I'll give Doug a heads up.

 

[brother]

Here is the second half - same document:

I search for that article 220.31 and i do not see it in the 2005 nor the 2008 code. I know its in the 2002 code. Is there a REASON they deleted this section??

 

[roger]

I search for that article 220.31 and i do not see it in the 2005 nor the 2008 code. I know its in the 2002 code. Is there a REASON they deleted this section??

No, there is no REASON because they didn't delete it, it was relocated, see 220.82

Roger

 

[jrannis]

A site plan so I can install a simple residential generator?

I am so glad I work here.

The power company would not be involved in it either.

Yes its quite a big deal. Dade County is worse. Forces the moonlighters to not get a permit

 

[BryanMD]

(I'm generally in the let the HO do what he wants in/on his own property camp)

Yes its quite a big deal. Dade County is worse. Forces the moonlighters to not get a permit

This is a GoodThing.

Aside from the practical aspects of assuring the "installer" actually understands what is needed to be understood for a given job (and especially one as complicated and critical to get right as Gensets/transfer switches...)

 

[Pierre C Belarge]

In the local counties around lower NY, there are so many different jurisdictions who mostly have their own requirements for generator installations.
Some are as strict as what Bryan posted, some are more strict...leading to the fact that some homes do not qualify to install a generator and some of those have gone to battery systems (GIAI).
The utility companies are also very interested in generator installs.
It has come to the point that the smarter electrical contractors are hiring a generator company to do all the leg work and the EC only installs the electrical.


It is not like the "old" days anymore.