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Disconnecting Means

Discussion in 'Charging Standards and Infrastructure' started by Cottonwood, Jun 28, 2015.

  1. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    Colorado
    Being an EV person, I have been asked to consult with adding EV charging to a new community center in my town. We are installing conduit from the electrical room to 4 spaces in the parking lot. For a cost effective, general solution, we will probably install one of the ClipperCreek Dual HCS-60 devices. This a nice setup with a pair of the HCS-60 EVSE's on a mounting pedestal offering a 48 Amp J1772 to each of two parking spaces. Because these are not more than 60 Amps and not more than 150 Volts to ground (each leg of the 208 Volt circuit is only 120 Volts above ground), the setup does not need a "Disconnecting Means," which simplifies installation.

    For background, here are two quotes from the 2014 NEC:

    625.42 Disconnecting Means. For electric vehicle supply equipment rated more than 60 amperes or more than 150 volts to ground, the disconnecting means shall be provided and installed in a readily accessible location. The disconnecting means shall be lockable open in accordance with 110.25 .

    110.25 Lockable Disconnecting Means. Where a disconnecting means is required to be lockable open elsewhere in this Code, it shall be capable of being locked in the open position. The provisions for locking shall remain in place with or without the lock installed.

    For the other two spaces, we will probably apply to the Tesla Destination Charging program for a couple of HPWC's to set up for 80 Amp charging; also, I have a 70 Amp ClipperCreek J1772 that I may donate to the cause. Both of these options will need a "Disconnecting Means" for currents over 60 Amps. I have found devices like the GE 100 amp 240-Volt Fusible Outdoor General-Duty Safety Switch-TG4323R from Home Depot. Does anyone know of any smaller, better looking, and/or less expensive solutions for a "Disconnecting Means?"

    Any other advice or suggestions are appreciated.

    Thanks ahead of time, TMC!
     
  2. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    #2 FlasherZ, Jun 28, 2015
    Last edited: Jun 28, 2015
    If you're on NEC 2014, you're lucky because a breaker lock may suffice. If you're still on NEC 2011, they have that specific language in art 625 that says no breaker lock-outs. Ask the local authority what his/her interpretation on "readily accessible" means in your case - it may be the case that a breaker in the electrical room is just fine and you won't need any special equipment.

    If the AHJ requires a disconnect near the HPWC's, a load center with a locking tang can suffice. I use a Cutler-Hammer BR816L125RP on the outside of my pool house for the pump and equipment. It's a square-ish box, 13" by 11" by 2" or so. A locking tang hangs out the bottom of the cover to which you could attach a lock for lock-out.

    Eaton 125-Amp 8-Space 16-Circuit BR NEMA 3R Main Lug Load Center-BR816L125RP - The Home Depot
    Eaton 100 Amp Double-Pole Type-BR Circuit Breaker-BR2100CS - The Home Depot

    Box is $40 and BR2100 breaker is $40, for total of $80.

    Here's what it looks like:
    344074bccab1dcdbd57e8aa672055055.jpg

    You can hang a lock on that tang at the bottom and it won't open.

    Another simple option is a mobile home disconnect:
    GE 100 Amp Outdoor Circuit Breaker with Enclosure-TQL100REP - The Home Depot

    That would be ~$65 per HPWC ($58 for disconnect plus $6.26 for hub on the top). You can even use this for your 70-amp Clipper Creek provided that your breaker in the electrical room qualifies as your 90A OCPD for the 70A load - you'd consider this merely a disconnect.

    The other option you have is to use a larger panel, a 200A panel per two spaces that has a similar lock-out provision, but 200A panels tend to be large because of the assumption for lots of breakers. You could use one of these per two HPWC's, fed with 3/0 CU or 250 kcmil AL.

    Eaton 200-Amp 12-Space 24-Circuit Type BR Main Lug Loadcenter NE mA 3R-BR1224L200R - The Home Depot
    (See above for BR 100 amp breaker link.)

    Cost would be $100 for panel plus $40 each for 2 100-amp breakers, or $90 per HPWC ($180 total).

    Or GE Q series:

    GE PowerMark Gold 200-Amp 12-Space 24-Circuit Outdoor Main Lug Circuit Breaker Panel-TLM1220RCUP - The Home Depot
    GE Q-Line 100 Amp 2 in. Double-Pole Circuit Breaker-THQL21100P - The Home Depot

    Cost would be $66 for panel plus $44 each for 2 100-amp breakers, or $77 per HPWC ($154 total).

    All of those options have the locking tang that would qualify as a lock-out. Don't forget the grounding bars. :)
     
  3. Rocky_H

    Rocky_H Member

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    @FlasherZ, In those boxes you're talking about, you're referring to being able to lock the boxes, so they can't be accessed. But that doesn't seem to be the lock-out that the NEC code is talking about. From those code descriptions: "The disconnecting means shall be lockable open in accordance with 110.25" "it shall be capable of being locked in the open position." I think this is talking about where you have a switch that can disconnect a circuit, and then you can physically padlock the position of that switch so that it cannot be flipped back on to activate the circuit again. In electrical safety classes, this is part of the "lock-out, tag-out" procedures.
     
  4. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    #4 FlasherZ, Jun 29, 2015
    Last edited: Jun 29, 2015
    The AHJ's I deal with have found that a panel door lock is sufficient for the "lock open" requirement of 110.25 - because you can turn the breaker off, then lock the door shut - which locks the switch from being closed (turned on). I've used this justification a few times without hassle. (Lock-out, tag-out permits a lock on a cabinet door to secure a switch in the open position as well. I used to tag the breaker and the panel door and apply the lock.)

    Note that you can also buy specific types of handle locks for breakers themselves. 110.25 requires that they be able to remain in place when not in use, so you must use one that allows for you to switch the breaker without removing the device. Escutcheon-mounted and screw-mounted locks work for this in BR panels.

    Of course, Code interpretation differs per AHJ and you might have someone who insists upon a specific breaker/switch lock (usually, this is due to familiarity of the older language used in the motor section of the Code, prior to 2014's centralization to 110.25 - it specifically said the switch or breaker must be locked for motors). My recommendation is to escalate and appeal.
     
  5. Rocky_H

    Rocky_H Member

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    Oh yeah, I guess I was thinking too directly, but that makes sense that it practically satisfies the condition, since the locked box will make sure the breaker inside stays in whatever position it's currently in.
     

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