[Nai3t]

My home charging project is close enough to completion that it's time to share it. This thread is a bit of an installation walk-thru, but I'll start with the finished product.

The EVSE I chose is a Clipper Creek HCS-50, but I've modified it by separating the charging cable from the box.

The 25-foot long, 40 amp charging cord discretely tucks into the outside alcove of the garage. The holster / cable hanger is from OpenEVSE and mounted to a piece of oil-rubbed mahogany to match the garage doors. The EVSE itself is installed inside the garage to keep the installation looking clean.

My original intent was to mount the complete EVSE box in this alcove (hence the patched bolt holes you can see on the stucco), but this last minute inspiration to separate the cable from the box won the day.

Since 2019 I've been happily Level 1 charging my BMW i3 mainly at work, or infrequently at home either L1 or sometimes L2 (Duosida dual voltage 16A EVSE), running an extension cord either to an outside 120 volt receptacle, or through the doors to a 240 volt socket I installed inside on the back wall of the garage. I didn't really "need" 40A capability for that car's relatively tiny battery, and knew the Clipper Creek was going to be an effort to install (as detailed in this thread). So the HCS-50 sat untouched on my workbench for 9 months.

Upon the addition of the ID.4 to our household, the time had come to install the Clipper Creek HCS-50.

We park on the street — my detached garage is more of a workshop than any place to store a vehicle, and we don't have a driveway. So while I had some flexibility with the extension cord I use to charge the i3, the HCS-50's 25 ft. cable constrained my installations options.

With the L2 charging cord extending from the square gray electrical box down low (photo), I've maximized its 25-foot length for the greatest reach out to the street. I also added a 240 volt / 20 amp receptacle (photo: brown weatherproof cover — note it's a split receptacle with 240v up top / 120v on the bottom) to this more convenient location outside of the garage, so I can simultaneously charge my i3, without having to open the garage doors and run the cord to the back wall. I'm really happy with how tidy this turned out.

I generally don't have to worry about our driveway being blocked, so the primary charging position is a given. Both cars have their charge ports on the right side, so I needed to maximize the available 25 feet of the charging cord. Had I stuck with my original plan -- mounting the EVSE box outside in the alcove and high up -- the cord would have been too short by a few feet, and I'd need to purchase a longer cable or an extension. Twenty-five feet with no extensions is the maximum permitted length by electrical code, but more importantly, it would be costly. To protect the cord and prevent a tripping hazard, I lay down this heavy rubber door mat (photo) where it crosses the sidewalk. I'm considering routing open the sidewalk joint to give the cable a deeper place to nest, but this current arrangement seems adequate.

About two months ago, having already purchased the wire and some of the other materials, I kicked off the project. The entire installation wasn't a true two months' effort — some of it was waiting for parts to arrive, or me just getting busy with work-work, plus an unforeseen setback or two. I'll walk through that further down.

I'm not a licensed electrician and am sharing this with the caveat that I've been doing my own electrical for quite a while and am comfortable with the work I did, but also know that I'm not 100% code compliant (I'll point those areas out that I'm aware of). I welcome to any criticism / critique as I, too, am always learning. For instance, in the second photo, I'm supposed to label this box "“For Use With Electric Vehicles" and I need to install a placard indicating where the shut-off switch is located, since it is not in view of the charging cable. The holster should be no greater than 4 feet off the ground, and the gray box should be at least 24" off the ground (my interpretation as the code refers to "outlets" not "receptacles"). For your reference, I'm using a guide from my utility that summarizes NEC and state code (https://www.pge.com/includes/docs/pdfs/about/environment/pge/electricvehicles/ev5pt3.pdf).

Let me mention some of the tools I used opening the concrete which I consider could be "less common" than what might be on the typical workbench.

First and foremost my eager 9 year old helper held the garden hose while I cut concrete, he vacuumed, cleaned out the trench, pulled wire while I pushed it from the other end, and cut and shrank the heat shrink. He's holding a Bosch Bulldog hammer drill for coring the concrete and cutting larger holes in concrete and stucco. He's sitting next to a cheapo Harbor Freight demo hammer which isn't great but gets the job done busting concrete, a pneumatic chipper for breaking up the smaller concrete chunks, and an oversized angle grinder with a 9 inch concrete wheel.

First item of work was what I was dreading most: opening up 6 feet of concrete sidewalk to run conduit from my main panel to the fence. The concrete cutting is messy once water is on the blade, so I put up plastic sheeting. After cutting the opening with a 9-inch angle grinder, I used the demo hammer to bust up the concrete. I got lucky with the rebar and didn't cut it. I also knew I had drain pipe and an existing electrical conduit down there, so proceeded carefully around them both.

Electrical conduit should be set at minimum 6" below a concrete slab, but with drain line in the way here and a lateral electrical conduit crossing on the other end of the trench, this is as deep as I'm willing to set it. I'll nest it with sand and compactable gravel, so if I ever need to open the concrete again, the conduit won't be embedded. The run straight across from the electrical panel to the other side will be obvious, so I'm not worried about somebody aka my future self "accidentally" finding it.

For the drop in, I used a box elbow off the panel to a pre-bent aluminum elbow, then a liquid-tight transition to PVC for the under-slab. My intent with the liquid tight (which is flexible) was to decouple the house-mounted conduit from the sidewalk-mounted conduit, to minimize the chance of cracking or pulling apart, since the two surfaces move independently. I probably need more of an 'S' bend in the LT conduit for this to work as intended, but I'll know in a few years if my plan worked, or needs to be revisited.

The metallic liquid tight conduit is galvanized steel inside with a thermoplastic jacket. It isn't extremely flexible — this here is about its tightest bend for the 1-inch size. It's easy to cut with a recip saw, and the end fittings simply screw on internally.

 

[Nai3t]

Coring the hole 13 inches down into the curb for the riser run was a challenge. Very slow going, an inch or so of drilling followed by a little bit of chipping to break up the concrete and extract it. Then I had to core in from the side and locate the bottom of the vertical hole, and open their intersection wide enough to slide in the PVC elbow.

Speaking of PVC, don't do what I did! Instead, use EMT or aluminum for a riser. Repairing this broken PVC adapter sucked! This happened after I already had the circuit in service for a few days. I had to send my wife back to Electrify America, open my wire splices, pull back about 10 feet of wire, trim the PVC conduit about 3 inches down in the hole, and add a transition coupling to aluminum. But I'm so glad I broke it before I poured the new concrete.

From the riser, a 6 foot surface run of aluminum conduit (the trash bins are normally parked along this curb, so not much of an eyesore), and another transition to liquid tight. The conduit and the replacement aluminum nipple coming out of the curb were the only "custom" pieces which I had my electrical supply cut and thread. I further "customized it" with my foot to follow the not-straight profile of the curb.

I decided to mount the conduit to roof blocks rather than attach it to the fence. Fences need to be replaced from time to time, they wiggle and get climbed on, and it may have resulted in a few more elbows rather than this relatively straight 2-turn run. I'll strap the conduit to the fence at the far end near the garage to prevent it from being pulled away, but this arrangement seems reasonable.

This was my first time splicing anything as heavy as 6 gauge wire. At the box on the garage wall, I transitioned from UF "underground feeder" to NM-B (aka Romex). Split bolts require a little bit of time it install, torqueing properly and safely taping. I started with a single layer of 1" heat shrink tube, followed by wraps of 3M "electrical repair tape" which bonds to itself, then finished with electrical tape. The finished built-up protective coat of insulation is supposed to be at least 1.5x the thickness of the insulation that came on the wire. I've safely exceeded that. I also took a Dremel to the extra wire and bolt threads sticking up to make these a little less pointy, and to shrink the whole taped-up package. I should have used a larger wall box for these splices and entry point.

UF wire is suitable for direct burial, but not recommended for conduit work due to its width and stiffness. Individual THWN wire would have been a better choice. But I had 20 feet of UF so I used it (...and I was one foot short -GAH! - and as such I've got ugly splices hiding inside the main breaker panel).

The box itself sits too close to the wall to directly screw in the liquid tight fitting, so I installed an offset nipple to provide the necessary space. This style female liquid tight fitting is apparently uncommon -- my two go-to electrical supply houses didn't stock them -- so this was an ebay order.

If it's metal, GROUND IT!

Transitioning between PVC and metal, let me stress this point. There is no electrical continuity through PVC. Any steel or aluminum enclosure must be grounded to avoid the risk of electric shock. When I was assembling this box the second time (following my repair of the broken PVC adapter), I stuffed the box too vigorously / carelessly. Two thin steel plates with pointed edges are screwed into place across the box opening (small plates that have threaded holes for the box cover to screw in to). The edge of one of the plates was pressed into the insulation of one of the wires, and it broke through the protective coating.

With everything assembled, I closed the breaker, and it tripped immediately with a violent BANG!, smoke wafted from the conduit, and when I opened the box saw all-too-obvious signs of a hot arc and damage to the wire and the plate, with black soot coating everything. Had I not grounded this isolated box, the breaker would not have tripped, and the box, the LT conduit, and the aluminum conduit would all have been carrying 120 volts, looking for a victim.

I shortened the cable (I had left it unnecessarily long), and I packed it more carefully the third time. However, as I commented above, this box is undersized for what I am using it for and I should have gone with the double-gang size like I used at the front of the garage. I also would have done myself a favor by cutting a larger hole into the stucco and installing my wire clamp properly on the back side of the box, taking up less space inside of the box. I wanted the smaller diameter hole in the stucco behind this narrow box for waterproofing reasons, but a larger (wider) box would have negated this concern.

Anyhow, make sure your metal parts are grounded.

Some of the tools I used for this portion of the installation: The yellow circuit sniffer is useful to verify there's no stray voltage in the wires. I use my smaller hammer drill for tighter spots and smaller holes in stucco. The two core bits -- one for stucco and one for wood -- were used for penetrating the exterior wall. Heavy duty cable cutters for working with large gauge wire. The roll of tape is rubber mastic "repair tape" that goes by different names, used to insulate the split bolt splices. The cable ferrule crimp tool puts a cap on the ends of wire to keep it from fraying when connecting under a terminal screw. I used the monkey wrench and pipe wrench for tightening up the conduit and fittings. The torque wrench got used on the split bolts to ensure proper assembly. And of course the heat gun for heat shrink tubing that was the first layer of insulation on the split bolts.

Here's an overview shot of the run from the main panel on the house to the entry into the back wall of the garage.

 

[Nai3t]

From the back wall of the garage, the wire enters the stud bay and begins a 40 foot run through two walls to the front. These photos show the wire unceremoniously entering from the back near the hose spigot, an access hole I cut under the sink to exit the garage to the front electrical box, and one of the crowded corners I had to pull the wire through a few inches at a time.

The 6 gauge wire is a bit of a chore to pull, especially around corners. I recommend a helper to minimize frustration. I followed the 6-2 with a run of orange 10-3 Romex, to supply the 240 volt secondary receptacle I added to the outside alcove. You can see the yellow pigtail hanging out of the wall in the photo below, which I rigged up to occasionally plug in to when I needed a slightly faster boost for my i3. Much more convenient with this receptacle out front, not having to run an extension cord through to the back wall!

The smaller circuit begins with a GFCI breaker (yellow Test button in photo below -- $100 breaker, yikes!) It runs to the right to an On-Off-On switch to select between the outside receptacle or the air compressor, then from there doubles back to the left along with the new 6/2 to run to the front of the garage.

BTW that's a 60 amp sub-panel in the photo servicing the garage. Its spots are all full, and it feeds a 30A air compressor (shared with the smaller EVSE circuit) and a modest 40A on-demand water heater. It would have been too much of a compromise — or just as much effort — to rearrange breakers, or swap in a larger panel to feed the new EVSE. In fact, had I done a better job planning this all out years ago, I likely would have still elected to feed the EVSE separately from the main distribution panel -- and would have had installed spare conduit under the concrete!

The tools for this phase of the work were minimal: close quarters drill, rotary saw, razor blade, and some magnets for locating drywall screws under drywall compound. I also used a wire fishing tape and rod to pull wire at a couple of locations.

I tacked a 1x2 piece of wood trim along the path where I wanted to open the drywall, and traced it with the zip saw, then ran a razor blade to finish the cut. This left me with fairly even openings, which will be easy to patch. I used the magnets to help me locate hidden drywall screws.

I'm sure Clipper Creek will tsk-tsk me for modifying their HCS-50 EVSE. I neatly cut a hole into the unit's back panel and supplied power directly into their box from the wall. Upon entering the box, power goes directly to their contactors as it normally would for a hardwired installation. However, instead of CC's 25-foot "charging cord" being connected to the output side of the contactors, I continued the NM-B wire run back out through the aforementioned hole, down the wall cavity, and out through the stucco to the back of the square gray box shown in my first photos in this thread (basically replicating the cable entry on the back side of the garage). Inside that box, I again used the split-bolt splice connections to connect to Clipper Creek's charging cord.

This wasn't the easiest setup to implement because the HCS unit has all of the electronics mounted to the face of the box.

• first I determined where I could run my wires into the wall, then located a suitable framing member to mount to
• I installed the two black 3/8 hanger bolts into the stud to mount the assembled EVSE
• using double-sided carpet tape on the back cover of the HCS-50, with the assembly screws removed, I fitted the EVSE to the hanger bolts
• when I pulled the EVSE away, the "loose" back plate remained adhered to the wall with the foam tape
• I drilled two pilot holes into the cover and drove screws to mount the cover plate to the wall
• from here, I determined the location of the wire access and drilled a 1-3/8 hole into the back plate
• when I mount the "face" of the HCS-50 onto the hangar bolts, it fits over the back plate to create a sealed enclosure without the backplate screws

It was also necessary to extend the blue pilot line from the EVSE box to the gray box outside. Code says not to combine power and signal wires in the same box, but I didn't really see a way around this as the pilot wire is encased in the charging cable that goes to the car, so they all travel together as a package through the wall space between the EVSE and the gray box.

Although I initially got it working as shown below, the five strands of 6 gauge wire proved too stiff to easily reassemble this box. So I devised an alternate plan shown in the following photo.

This was my take two! I installed a terminal block on the backplate (drilled through to the stud) so the stiff feeder wires could just be bent into position, connected, and not touched again, nor accordion-folded into the box in such a way that they might exert pressure against any internal components. I then used supple 6 gauge "battery / welding wire" to make the final connections form the terminal block to the contactor.

The ferrule crimping tool is great for ensuring any wires under a terminal screw are making good contact and not creating a high resistance hot spot, particularly on these thin-strand battery cables.

As an alternative to the terminal block, I could have relocated the EVSE's contactor to the back plate, and extended the control wires as necessary, negating the need for the extra battery cables.

I found a couple of black plastic knockout plugs to close up the former in-and-out holes on the bottom of the EVSE, plus some black nuts to give it a finished appearance.

With this flexibility of decoupling the charging cord from the EVSE I was able to mount the box high on the wall and out of the way. It even makes a nice place to hang an extension cord. But I'm most pleased with its visible absence outside the garage, which would have entailed an extra length of conduit and added clutter to the alcove. I've got enough clutter inside!

Finish up work will be mainly drywall and concrete patching. I also set myself up to run 240v to the other side of the front of the yard through buried conduit, to give myself one more curbside 20A charging option. I'm reasonably optimistic that what I did here isn't overly specific to the Clipper Creek unit, and should the need arise I can swap in a different brand or model down the road without much fuss.

The question comes up all the time on various EV groups: How much should a Level 2 EVSE installation cost? If I was an electrician quoting this job, I know the answer; "A Lot!"

 

[Drew]

From the back of the garage, the wire enters the wall cavity and begins a 50 foot run to the front.

View attachment 3971

I opened the garage wall with a palm router. To get straight cuts, I tacked a strip of 1x2 trim along my path, and followed it with the router. This will make cutting drywall patches easy, when I eventually get around to that step. This portion of the wiring was relatively uncomplicated: drill holes, pull wire. 6 gauge wire is a bit of a chore to pull, especially around corners, and I installed a run of 10-3 alongside it for my 240 volt secondary outlet.

View attachment 3969

I doubt Clipper Creek will be excited that I modified their EVSE. I neatly cut a hole into the unit's back panel and ran directly into it from the wall. The wire runs directly to the contactors as it normally would for a hardwired installation. However, instead of the 25-foot "charging cord" being connected to the output side of the contactors, I continued the NM-B wire run back into the wall, down to the little gray box shown in my first photos in this thread. Inside that box, I replicated the split-bolt spliced connections to connect to Clipper Creek's charging cord.

It was also necessary to extend the pilot wire from the EVSE box to the box outside. Code says not to mix high voltage and signal wires in the same box, but I didn't really see a way around this, and they all travel together as a package.

With this flexibility of decoupling the charging cord from the EVSE, I was able to mount the box high on the wall and out of the way. It even makes an nice place to hang an extension cord. But I'm most pleased with its absence outside the garage, which would have entailed an extra length of conduit and added clutter to the alcove. I've got enough clutter inside!

View attachment 3970

View attachment 3972

Wow, that's quite a setup. Nice work.

 

[Nai3t]

Since posting this 2 weeks ago I've been fiddling with the installation, as well as the text and pictures in this thread.

Today may be my final edit, after installing a terminal block inside the EVSE box to clean up the wiring. The unit's been humming along just fine this whole time.

I'll update if something starts smoking!

 

[TriangleID4]

Filing this under "Do-it-Yourself Legends"

 

[Huey52]

Yes indeed, one of my favorite threads as well. Truly inspired and very well done work!!

Filing this under "Do-it-Yourself Legends"

 

[Nai3t]

Thanks fellas. I wish I had something interesting to add, but it's been out-of-sight, out-of-mind, working reliably and free of fuss.

I haven't repaired the concrete yet — I have some concrete work to do coming up or might clean up the cut and place a row of pavers over it instead, but I'm thinking I ought to replace that second PVC riser with aluminum before I do anything.