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I-T-E Modular Metering

Discussion in 'North America' started by physicsfita, Apr 23, 2016.

  1. physicsfita

    physicsfita Member

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    #1 physicsfita, Apr 23, 2016
    Last edited: Apr 23, 2016
    Apologies if this has been covered elsewhere, but my searching turned up nothing...

    I reserved a Model 3 (yay, me!), and mow my attention is turned towards what I may need to ask my HOA for when installing an EVSE. I live in an apartment-style condo where each building has 4 units with shared garage space (with assigned parking) in the basement. Conveniently for me, the DTE feed for my building (and half of the neighboring building) is in a utility room in the basement level -- I don't think it would be a big deal to run a line to the pillar next to my garage door and mount an HPWC on the pillar.

    What I don't understand is how the power gets split coming in to the building. The feed from DTE comes in to the box on the left in the photo, and the label says it is rated for 800 A. The boxes in the center and right each have 3 meter pans with 100-A master breakers under them. The panel in my unit on the 2nd floor is a subpanel with no master breaker. Since everything in the unit is electric except for the furnace, I suspect I need to increase capacity. Ideally, I'd like to get a second meter from DTE so I can take advantage of their EV rate plan (a separate meter is required).

    What options are available to me with this setup? Any advice is much appreciated so I can get my proposal to the HOA in order (I know this is a couple of years out, but I want to start navigating the politics sooner than later). Thanks in advance for any help/ideas!

    image.jpeg
     
  2. AEdennis

    AEdennis Active Member

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    Your rights in shared housing situations vary state to state (much like ordering a Tesla). There was a thread (California based) recently started called "I Won" or something like that may offer hints (found it), as well as many other threads of the strategies others have done. But it seems that things can get contentious.

    Good Luck and Congratulations
     
  3. GSP

    GSP Member

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    Physicsfita,

    Congratulations on your reservation!

    Depending on how many miles you drive per day, almost any 240 V circuit will be enough, even just a 20 A breaker. I would get an electrician to do a load calculation on your panel and tell you how much load you can add for your HPWC. Also get a quote for installing the HPWC. You may want to get 2-3 quotes, since they can vary a lot.

    The HPWC can be installed with just about any breaker size from 15-100 A. If you want more than what the load calc says you can add, consider reducing your load by converting an appliance to gas.

    If you haven't already read FlasherZ's charging FAQ, I recommend it (see link in his signature).

    Good Luck,

    GSP
     
  4. physicsfita

    physicsfita Member

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    Thanks -- I have read the FAQ, and it's awesome. My commute is 120 miles round-trip, with no charging available at work. This is in Michigan, so I need margin for winter weather.

    The hot water is already gas (forgot to mention that earlier), and my neighbors say there's something funny about the gas line runs that makes the HOA turn down requests to make anything else gas, so converting the dryer or stove seems out of the question. Also, with the subpanel two floors up, the wiring back down to the garage would be a mess (unless there's another way to do that).

    That's leaving me with dropping in another meter pan -- there's space, but I'm trying to figure out if it can be done with this system. If that can't happen, could the 100-A breaker be made bigger, and another subpanel daisy-chained in somehow? I would have to pay full-price for the electricity, but the extra price per kW-h might be ok if the other options are prohibitive to install.
     
  5. physicsfita

    physicsfita Member

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    Thanks for the good wishes! Although Michigan doesn't have anything to force an HOA to allow charging (that I'm aware of), I've been told mine's pretty good about allowing owner-paid projects (as long as it doesn't involve the natural gas -- something weird is up with that).
     
  6. FlasherZ

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

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    Hi,

    There are a few different options that you likely have there.

    1. You could ask that a second set of lugs be attached to the base of your meter to feed a second service panel immediately adjacent to that 100A breaker. That panel would then be metered by your own meter (cutting down on service charges). This is similar to how my second HPWC is set up - I have 3 lugs at the base of my meter - one goes to the generator-protected ATS for a service disconnect, one goes to the grid-only panel serving the remainder of my home (including HPWC #1), and a third goes to a 100A disconnect for HPWC #2. Upside is that you get a single bill. Downside is that with your appliance situation, if the meter pan is only rated at 100A per meter, you probably can't make load calculations work out.

    2. If that's not acceptable, they can add another 3-meter cabinet to the right there and supply you with a second meter. Downside is that you'll pay two meter/service fees on two different accounts. Upside for the HOA is that it keeps things segregated a bit better - dwelling units are all consistent, no special configs, and the add-on is a completely separate account. This is also advantageous because of your appliance situation, it won't take away from your 100A. There may still be some load calc issues, though - they may only have provisioned all units with 600A service total.

    3. If that's not acceptable, you can ask them if they would be willing to place a subpanel on the wall there. You'd feed that subpanel from the 100A breaker, and move the feeder from your dwelling unit into that subpanel along with a branch circuit for a NEMA 14-50/6-20/EVSE or something that would work with your car. They would likely reduce the breaker size that feeds your unit in the subpanel, though, and load calculations would have to work out. You may end up having to install an HPWC with current down to 20 or 30A to fit your load calculations.

    4. The final - least desirable - approach would be to run a circuit from your panel inside your unit. Lots of cost to do the homerun, but it might make the HOA happy because it keeps all common infrastructure the same and can be ripped out easily if/when you move.

    Does this help?
     
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  7. physicsfita

    physicsfita Member

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    Thanks! That does help a lot. It seems (if DTE and the HOA go along) that the second choice would be the best. DTE's service charge for the special EV-charging account is only $1.50/mo, so connection fees aren't a big deal. I drive a lot of miles (120 round trip on my commute days and 40,000 per year). Factoring in winter weather, it seems like a 20- or 30-A solution is suboptimal, if I've done my charging math correctly. Considering that the house meter for parking-area electricity is on the sister installation on the opposite side of my building (along with 6 more dwelling meters), there must be enough to at least support that. (I don't have the key to that party of the building, so I don't know what was done there.)

    Thanks so much!
     

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