Code Change of the Week

This section gives us a date to stop making connections to an equipment grounding conductor on January 1, 2020, at switch locations that have electronic dimmers or controllers installed.  After that date we need to be using a neutral conductor to make these devices work,  no longer allowing the equipment ground to be used for this purpose.  Although a neutral is not necessary at all switch points section 404.2 C instructs us when and where a neutral is needed. And with all good Code changes there are exceptions,  this does not apply to replacements or retrofits, and has a limit of 5 (five) devices per branch circuit and 25 (twenty five) per feeder connected on the load side in the system or main bonding jumper. A neutral busbar in compliance with 200.2 B has no limits as to the number of electronic devices connected to it.

Can’t see the whole picture just click on it.

Have a question email me at jleccemail@hotmail.com

Till next time be safe work safe.

Jake

New to this section the reinforcing steel that forms a swimming pool shell.  A swimming pools’ steel cage is not to be used as part of our grounding electrode system.  I have heard stories where the inspector required that the contractor run the pool bond back to the ground rod?  This practice a “violation” and could endanger the occupants of the pool with stray currents or ground-fault current introduced on this grounding electrode system.

Can’t see the whole picture then just “Click” on it.

Till next time be safe work safe.

Jake

This week we will start a series of Code Changes found in the 2017 NEC.  Every couple of weeks we will explore one of the changes.  If you have questions please email me at jleccemail@hotmail.com.  REMEMBER THESE ARE NOT IN USE BECAUSE THE FLORIDA BUILDING COMMISION HAS NOT ADOPTED THE 2017 NEC YET!!!!!

The first one we will look at is in Article 110.14(D) Installation (of devices outlets, switches etc., etc..).  This new section requires us to torque all connections that require torqueing which would now include switches and receptacle outlets, or any equipment that has a numerical value on the device or in the instructions provided by the manufacturer.  A couple of manufacturers have come out with devices that come with a snap in tails which would not require torqueing.  See the slides below, if you can not see the entire slide just click on it to make it bigger.  

But for those who don’t have the snap in tails , you will need a torqueing screw driver.

Till next time be safe work safe.

Jake

Question came up this week in reference to having a service outlet near the service equipment.  I referred them to section 210.64 and told them one was required, except at a one-family and two-family dwelling. This would be for service equipment installed both inside or outside of a building.   If you install a 480 volt service make sure to put in a small step down transformer in order to comply with this section………..

Till next time be safe work safe

Jake

First of all for today I hope you all enjoyed the day off to celebrate the annual Labor Day holiday.  You all work so hard an a day off to celebrate that hard work is deserved.

Todays news letter has to do with Arc Flash reduction, which is a requirement of the Code to help reduce an arc flash incident if one was occur when someone was working on a live “Hot” piece of switch gear.  The methods described in the article would allow someone to work on a main switch or disconnect that is hot and set the breaker or by-pass switch to maintenance mode so that if an incident was to occur it would clear almost instantaneously reducing the incidents arc flash. Thereby giving the worker added protection from a possible disastrous arc flash incident. 

This section first introduced in 2011 has been updated in the 2014 giving us some additional ways to reduce the hazard for workers who are working within the Arc Flash Boundary as defined NFPA 70E.  Based on the 2014 guide lines for mitigating the hazards of working on energize switch gear, there are now several ways to limit the time a circuit breaker will  take to shut off reducing the arc flash incident. All of these methods will require you to research the methods to find the one that works for your installation. 

A few contractors have asked about ways to work around this code article, especially ones who are working on high end residential projects.  Homes with 1200 ampere services or larger.  One way would be to have multiple mains smaller than 1200 amperes or use fused disconnects for mains, both which are not covered by this article. 

When designing and building a service this large you would have to have an engineer involved because of Florida statute 471.003 h which only allows an electrical contractor to design and build a residential services up to 600 amperes at 240 volts, and commercial services up to 800 amperes at 240 volts.. So next time you encounter a large service (1200 amperes or larger) commercial or residential maybe you can suggest a couple of smaller mains rather than going with the larger one.   

See the Code section 240.87 below:

240.87 Arc Energy Reduction

Where the highest continuous current trip setting for which  the actual overcurrent device installed in a circuit breaker is rated or can be adjusted is 1200 A or higher, 240.87(A) and (B) shall apply.

(A) Documentation. Documentation shall be available to those authorized to design, install, operate, or inspect the installation as to the location of the circuit breaker(s).
(B) Method to Reduce Clearing Time. One of the following or approved equivalent means shall be provided:

(1) Zone-selective interlocking

(2) Differential relaying

(3) Energy-reducing maintenance switching with local status indicator

(4) Energy-reducing active arc flash mitigation system

(5) An approved equivalent means

All of the ways to minimize an arc flash incident will have to be done under engineering supervision in order to meet one of the five methods required in the above Code section.

Till next time be safe work safe.

Jake

Out in the field we do it all the time, we back feed a transformer with 208v and boost it up to 480v to feed a piece of equipment, or to use it to help with voltage drop in a long run, but now the Code has made it a requirement to be done in accordance with the manufacturer’s instructions.  Not all transformers have these instructions.

Have a question you like answered, email me at jleccemail@hotmail.com

Till next time be safe work safe

Jake

This is a new requirement in the 2014 Code that has already been amended in the 2017 Code.  In the 2014 it requires a 15 or 20 ampere receptacle

to be installed within 50’ of the service area.  Then in the 2017 Code they amended it so that a receptacle will not be required if the voltage of the service

is above 120 volts to ground for services in and around Electrically driven or controlled irrigation machines or near natural or artificial bodies of water in

articles 675 and 682 .

2017 NEC 210.64 Exception No. 2: Where the service voltage is greater than 120 volts to ground, a receptacle outlet shall not be required for

services dedicated to equipment covered in Articles 675 and 682.

So in the picture below you would have to add a transformer and panel to feed a 120 volt GFCI protected receptacle unless it is a service for equipment

covered in articles 675, and 682..

Till next time work safe be safe……

Jake

This weeks comments comes from a recent inspection where the inspector asked the contractor to show a listing for the fixture that he was using next to a pool, that would meet the requirements of this new Code Section 680.22(B)(6). His request was to show that the two (2) wire fixture did not need grounding.  The fixture was listed as a low voltage luminaire but did not specifically show that it did not need grounding.  The fixture had only two wires and nothing in the manufacturers instructions show grounding the fixture. I asked the contractor if the inspector checked out the type of transformer he used and he said he did not.

The second part of this new section was the use of a transformer that met the requirements of section 680.23(A)(3) which means it is list for use as a pool or spa as a power supply to a fixture. (isolated winding type with an ungrounded secondary that has a grounded metal barrier between primary and secondary or an approved system of double insulation between the primary and secondary windings)  The transformer would also have to have specific low voltage contact limits as laid out in 680.2 definitions. (15 volts (RMS) for sinusoidal ac, 21.2 volts peak for nonsinusoidal ac, 30 volts for continuous dc, and 12.4 volts peak for dc that is interrupted at a rate of 10 to 200 Hz.)

This is a new change which allows us to install Low Voltage lighting right next to a pool, the fixture not being grounded is a requirement of this section but only one of three requirements of this new section, so you have to pay attention to the total section when installing lights next to a pool or spa.  Make sure that you are complying with all the requirements of this section.

Click on the picture below to see the whole slide

Till next time be safe and work safe.

Jake

Got a question?  Send it in, I will try and get you an answer.