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Saturday, February 29, 2020

New NEC Code requiring Disconnects on Outside Residential Services safer for Firefighter? Not really can be dangerous

Yes NFPA really did not think this one thru when they passed in the 2020 code cycle that all new 100 and 200 amp residential service must now include an outside disconnect.

On its surface its a good code designed to protect Firefighters so they do not have to wait for the power company to  shut off power which can take 15 to 45 or more minutes to arrive.

But are we setting Firefighters up for failure and accidents with this new code ? Absolutely and are we putting public at risk ? again Absolutely.

As you dive further into this new code the outside disconnect can be a breaker rated for switch duty or a pull handle type disconnect.

1st its going to drive up cost of Job by several hundred dollars and they are already going near $2000 mark as it is with all the new requirements for AFCI and GFCI Breakers etc. more money home owner has to spend and less they can contribute to local charities and VFD

2nd it will encourage home owners to change there own breaker panels and do work they previously would not of tried because they could not shut off the meter . This will ultimately result in more fires due to home owner and handyman wiring negligence .Putting Firefighters at risk who repond to these fires.

3rd it will lead to Firefighters accidents because those outside disconnects age they deteriorate especially breakers and 20-30 or more years down line breaker may not shut off properly or can arc and cause explosion hurting Firefighter turning it off .
Also only one side of 220 service could shut off other 120 leg could still be hot and unless Firefighters check with a Hot Stick they could still have power on in home when they think it is off.

Yes another fine example of NFPA passing a code and not thinking it fully thru. and in 20-30-40 years my predictions will come true as usual.



1 comment:

  1. I'm curious with the exterior panel now considered the main service disconnect. The interior load center will required to be a 4wire sub panel. How will the grandfathered 3wire dryer/range ckts be addressed with their 3rd conductor serving as both the neutral and equipment grounding wire? Land it on the isolated neutral bar, you just bonded the neutral and grounding sub panel terminal bars together through the appliance's frame or land it on the sub's equipment grounding bar and you'll have half the appliance's return current flowing back on it to the main service equipment. And take in consideration if the appliance ckt is a SE cable the uninsulated wire can inadvertently touch the load center tub, again think....unintentional bonding.

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