Installing a Bosch EL-51253 Power Max 30A Level 2 charger:

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studio460

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Bosch EL-51253 30A EVSE: [Note: The original post has been edited for improved accuracy.]

Based mainly on price and appearance, I purchased a Bosch EL-51253 Power Max 30A Level 2 charging station with an 18' SAE J1772 connector/cable from Amazon ($569.55, with free two-day Amazon Prime shipping).

Bosch%20EL-51253-1.png


It's a good-looking unit, though not as pretty as the Schneider EVlink (which is only rated for indoor use). My installation is outdoors, so I chose the Bosch instead, since it's rated for both indoor and outdoor use. As other Amazon customers have noted, it's actually bigger than it appears in photos. The white plastic housing is nearly pure-white, and has a clean, modern look. I'm mounting this outdoors on the front porch (though it's still in a covered area), where it will only be a few feet from the car's charging port.

New 240V service:

When I upgraded our service panel for a kitchen re-model a few years ago, I had a 200A, 40/40 Cutler-Hammer panel installed by a professional electrician. This is a large panel with plenty of extra space for the new service (if you have an older, smaller panel, with a lower total amperage rating, you may need to upgrade your panel first). The job will entail running about 65' of metal conduit from the panel, under the eaves, through the garage, and finally to the front porch, onto an exterior wall, where I've already installed the mounting plate.

Circuit-breaker: 40A/dual-pole.

Apparently, a 40A breaker is what you need to accommodate a continuous, 30A-draw (to comply with the necessary 20% minimum safety margin). So, I bought a 40A/dual-pole, Cutler-Hammer breaker from Home Depot for about $10 (according to code, you're supposed to install breakers from the same manufacturer as the service panel).

Bosch%20EL-51253-6.png


Wiring: #8 AWG

I finally was able to determine the proper wire gauge to use for a 240V/30A Level 2 charger (it's not in the manual). The correct gauge is #8 AWG, copper, stranded (for easier installation), for a continuous 30A current-draw (even though our cars don't draw that much). This is for runs under 100'. For runs over 100', #6 AWG is recommended (to avoid voltage-drop) by the industry site I referenced.

Wiring diagram:

So, not a lot of information in the Bosch manual (e.g., all it says is to, "connect each [wire] to the correct terminal."). Small relief markings above the post terminals indicate a ground symbol, and the letters, 'N' and 'L'. Assuming that 'N' stands for "neutral," this is incorrect, since the neutral isn't used in a 240V hook-up. This is likely meant for the 120V version of the Bosch EVSE (which does use a neutral), and Bosch just used the same mold for the 240V version of the product.

However, the wiring diagram in the Bosch manual correctly labels these same terminals as 'G', 'L2' and 'L1'. This made immediate sense to my electrician, where 'L1' and 'L2' indicate "line 1" and "line 2," meaning the two "hots" (again, the neutral isn't used in single-phase 240V installations, only a ground and two "hot" lines).

Here's a close-up of the post terminals:

Bosch%20EL-51253-7.png


Note that the sticker says to use copper conductors only. The manual also indicates the proper terminal-post, screw-tightening torque specification (4.6 lb.-in.). Here's the Bosch instruction page on terminal wiring connections (note that the manual is printed in black-and-white):

Bosch%20EL-51253-2.png


Post terminals:

The Bosch instructions say to attach the wiring to the terminal posts using terminal rings. Initially, I bought the wrong terminal rings (designed for #12-#10 AWG), which are too small for #8 AWG wire. Note that most terminal rings carried by home improvement stores are designed for smaller-gauge wiring, and those that aren't have a ring size too large to fit onto the Bosch post terminals. So, instead, what you want are "mechanical lugs," made out of copper (with stainless steel screws). Note: DO NOT use aluminum terminal rings; see post later in thread for recommended copper lugs, available from Home Depot: (e.g., Burndy KA8CBAG2R or equivalent).

Bosch%20EL-51253-5.png


Conduit size:

As for the conduit size, I found this online at some electrical industry site:

conduit2.png


Knock-out:

One last thing . . . Bosch wants you to drill a hole in the bottom for the conduit access (indicated by the green arrow). They say, "be careful," so that you don't damage the plastic housing (it would've killed them to provide a knock-out?). Also, since I have to drill a hole for the conduit, why is there a molded plastic fitting right next to it? What's that for? All drawings in the instructions show the user-drilled hole next to the molded fitting, with no mention what the fitting is for:

Bosch%20EL-51253-4ARROW.png


Security:

Sorry, one more thing . . . Bosch recommends using a flexible conduit for the last few feet to make mounting easier. I've asked my electrician to just run the metal conduit right up into the box for an added layer of security against theft. Also, the provided screws which attach the unit to its mounting plate are Torx #30 screws. I may also fasten metal 'L' plates to the house siding to prevent access to the Torx screws (any would-be thief would first have to unscrew the metal plates).

I welcome any further comments, corrections, or suggestions!
 
Looks like you've thought it out pretty well. One thing I would suggest would be to run 3/4" conduit so that you can run 6 AWG in the future. (I would run the 6 AWG now, but that's up to you.) That way, if you get an EV in the future that pulls 40A, it's a simple EVSE and breaker swap. If you run 1/2", you're stuck.
 
Thanks for your reply, sefs. Yeah, I think I'll run 3/4" conduit so that I can also stick some 120V wire in there to power Xmas lights or something. I don't plan on buying a Tesla anytime soon (or, ever, actually--nice cars--just running out of money to buy cars!), so the #8 AWG should be fine until my FFE dies in eight years. Wait . . . actually, according to the chart, I would have to run 1" conduit to use #6 AWG, since the 3/4" conduit is only rated for two #6 AWG conductors, right?
 
No, 3/4" you're fine.

Your current setup would be:
2 8AWG
1 10AWG Ground
2 12AWG

Your possible future setup would be:
2 6AWG (Could do 3 also if you wanted to do something like a NEMA 14-50R)
1 10AWG Ground
2 12AWG

Both of these setups are fine with 3/4". I always suggest going 12 AWG and doing a 20 amp circuit minimum for any new branch circuit you're adding in.

Here is the raceway fill calculator I use: http://www.electrician2.com/calculators/rf_calculator.html
 
Notes above seem good. Reminds me of things I saw in the [similar?] EL-50600 I bought 2 years ago, when supplied through spx (now Bosch, I think).
Point to watch for, over time: I recommend that you feel the area where J-1772 connector meets the car, after it has been running for an hour or 2. OK to warm up slightly, but not get hot. (I checked right after turn-off and disconnect. Still do that now.)
That EL-50600 device worked great for me, BUT I think the connector deteriorated. Ran it at 24 A for year or so, then switched it to 16 A when I felt the connector at the car was warmer than I liked ... within half a year more, it Still got quite warm, so I bought a different EVSE (by Clipper Creek).
Your device Might use same REV-1-30C / REMA cable + connector as my original.
 
Thanks for the head's up! I'll keep an eye on it. What do you think caused the added resistance? Corrosion? Poor materials/assembly/design of the Bosch connector?
 
I don't know the cause. Could be thin or poor material that led to reduced contact pressure, or corrosion, or ...? New device feels much less warm to my touch. Might look for a replacement cable, if see how to disassemble / repair the connections inside the EVSE (the basic spec's and performance are good).
 
studio460 said:
Bosch EL-51253:

So, I'm planning to buy a 2014 FFE next week, so I wanted to have a Level 2 charging station ready by the time I got the car. So, based mainly on price and appearance, I just purchased a Bosch EL-51253 Power Max 30A Level 2 charging station with an 18' SAE J1772 connector/cable from Amazon ($569.55, with free two-day Amazon Prime shipping).

It's a good-looking unit (though not as pretty as the Square-D EVlink), that's rated for both indoor and outdoor use. As other Amazon customers have noted, it's actually bigger than it appears in photos. The white plastic housing is nearly pure-white, and has a clean, modern look. I'm mounting this outdoors on the front porch (though it's still in a covered area), where it will only be a few feet from the car's charging port.

Electrical hook-up:

I considered installing a new 240V circuit myself, but then decided to call an electrician, who's now scheduled for next weekend. The job will entail running about 65' of metal conduit from a 200A service panel, under the eaves, through the garage, and finally to the front porch, onto an exterior wall, where I've already installed the mounting plate. Since the Bosch instructions are completely void of any "instruction," I thought I'd jot down what I've found here. If anyone sees any errors, please feel free to point them out.

How did your EVSE installation end up?
About how much was the total electrician cost including permits, etc.

Schneider-Electric-EVlink-30-amp-indoor-outdoor-EVSE-90x90.jpg

I purchased the Schneider Square-D EVlink EVSE 240v/30a model myself ordering thru Home Depot (90 day return policy) since they have had a $100 coupon code discount on that model for the last few months and continues this month as well bringing the total price down to only just under $500 + tax and free shipping.

I'm getting local electrician quotes now for installing the EVSE including adding a 40A breaker in my existing breaker panel, and using about 30feet of #6 or #8 wiring to get 240V to the other side of the garage. First quote the electrician estimated $600 minimum (thats if the EVSE is like a foot away from the breaker panel) but with my custom distance it would be $720. That seems a bit high to me, I was hoping for under $500 since I purchased the EVSE myself, trying to get the entire thing to under $1000 total.
 
studio460 said:
Note that the sticker says to use copper conductors only. Well, the only ring terminals I could find are made of aluminum (what are the posts made of?)
Mixing copper and aluminum is a big no-no. Aluminum in contact with copper will deteriorate due to galvanic corrosion, and eventually cause problems (including potential dangerous overheating) with the connection.

In general, you either go all-copper or all-aluminum in home wiring. There are special techniques to combine the two if necessary (i.e., hire an electrician who knows what they are doing in this regard) but, for the DIY-er, it is probably highly advised to simply avoid mixing the two.

http://homeguides.sfgate.com/problems-aluminum-copper-wire-electricity-86313.html
 
Awesome! Thanks! I've been wondering what to do about this since I couldn't get to an electrical supply store today and the electrician's coming tomorrow morning. So, you have the same Bosch EVSE, and those were able to fit onto the Bosch's terminals?
 
NightHawk said:
I purchased the Schneider Square-D EVlink EVSE 240v/30a model myself ordering thru Home Depot (90 day return policy) since they have had a $100 coupon code discount on that model for the last few months and continues this month as well bringing the total price down to only just under $500 + tax and free shipping.
Yes, that's the unit I would've preferred but it isn't rated for outdoor use. Prettiest EVSE there is. Super deal you got!

NightHawk said:
How did your EVSE installation end up? . . . First quote the electrician estimated $600 minimum (thats if the EVSE is like a foot away from the breaker panel) but with my custom distance it would be $720. That seems a bit high to me, I was hoping for under $500 since I purchased the EVSE myself, trying to get the entire thing to under $1000 total.
It didn't yet--it's happening tomorrow morning. I got a quote from a electrician of $450 for a 50'+ run of 3/4" conduit under the eaves, through the garage, and around the porch. This, going through two walls. He's going to add a 120V box mid-run for Xmas lights for an additional $150. So, he's more on the "reasonable" side, I think.
 
WattsUp said:
Mixing copper and aluminum is a big no-no. Aluminum in contact with copper will deteriorate due to galvanic corrosion, and eventually cause problems (including potential dangerous overheating) with the connection . . .
Yeah, I thought applying anti-corrosion grease was the answer, but I guess not. But thanks to noflipping's post I think I have the appropriate solution now.
 
studio460 said:
Yes, that's the unit I would've preferred but it isn't rated for outdoor use. Prettiest EVSE there is. I got a quote from a electrician of $450 for a 50'+ run of 3/4" conduit under the eaves, through the garage, and around the porch. This, going through two walls. He's going to add a 120V box mid-run for Xmas lights for an additional $150. So, he's certainly more on the "reasonable" side.

Did your electrician do all the required docs for permits (cost over $100 or so just for that I believe) and schedule an inspector to look over the final installation? Some lowball quotes from electricians I'm concerned might not include that and I might get hit later by the city and/or electric company if I didn't have the required permits and inspection? One electrician that gave me an estimate does all that, but another who came by today didn't think they are required - so that had me concerned about some of them.
 
All quotes I get from tradespeople do not include permit fees. For any permitted work, I just supply any required drawings myself and pay for the permit myself at the city. I'll schedule the inspector also. All very easy once you've done it. But if that quote includes all that, that saves you the trouble.
 
Ha! That's why I'm not an electrician! I thought 'L1' and 'L2' meant "Level 1" and "Level 2" charging. These indicate the two hot legs in single-phase 240VAC power:

Line, single-phase: L1= BLACK
Line, single-phase (i.e., "second hot"): L2= RED

What I don't understand is polarity. One leg is +120V, and the other is -120V, and when summed, equal 240V [the neutral (white) has 0 potential, and is unused].

[Don't quote me on any of this, because I don't really know what I'm talking about.]
 
studio460 said:
Circuit-breaker: 40A

Apparently, a 40A breaker is what you need for a continuous-draw connection rated at 30A for a safety margin. So, I bought a 40A/dual-pole [corrected], Cutler-Hammer breaker from Home Depot today for about $10 (according to code, you're supposed to install breakers from the same manufacturer as the service panel).
I don't know if it was a typo, or a mistake. I originally spec'd a 40A/single-pole breaker--it should be a 40A/two-pole breaker (which is what I bought, and is what was pictured).
 
cwstnsko said:
We are talking about AC power which stands for Alternating Current. Each leg of the the "hot" wires alternates between +120V and -120V 60 times per second. The 2 legs alternate out of phase, so that when one is a +120V, the other is at -120V, so there is 240V difference between them.
I realize that alternating-current "alternates" at 60Hz, out-of-phase, resulting in the "summed" 240V total potential. But, does that mean polarity doesn't matter in 240V single-phase applications? Only in hot-neutral 120V applications? In other words, it doesn't matter which terminal (L1 or L2) the black wire goes to, and which terminal the red wire goes to, since they're both, alternating "hots?"
 
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