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Bolt/Volt Adapters

The small mobile EVSE that comes with Bolts and 2016 Volts and newer is actually capable of charging more than twice as fast when connected to a 240V receptacle. While this EVSE only comes with a fixed 120V 15A household plug, you can plug it into a "pigtail" adapter and charge from 240V receptacles.

Click here for a store that sells high quality versions of these adapters for all types of receptacles including RV receptacles, electric dryer receptacles, air conditioner receptacles, etc.

These adapters are not hard to make, and the rest of this page shows you how.

Note that there are companies that sell "conversions" to convert your EVSE to a 240V EVSE, but I don't recommend them. In the end, you lose the ability to easily charge from 120V sources, and they'll charge you $200 for permamently converting your EVSE to 240V. This solution here is just an adapter that you can use or remove as you need.

The theory of operation here is simple. Your mobile EVSE has a regular household plug with the bottom round pin being the safety ground, and the two other blades carrying 120V and a neutral return to complete the circuit. These adapters are going to feed 240V onto those two blades. The EVSE is designed to work with 240V, so it will happily draw its rated 12A from whatever 240V source you give it.

Extension Cord

When plugging in your car away from home using a mobile EVSE, it is always a good idea to carry around an appropriate extension cord as receptacles are usually farther away from where you can park your car. For the Bolt/Volt EVSE, a regular 120V extension cord will work as the EVSE has a regular household NEMA 5-15 plug. Just buy a heavy duty one that is at least 12 gauge or better (ie. 12 or lower gauge), and at least 50' long.

Special Settings?

The nice thing about these particular adapters and the Volt/Bolt EVSE is that you don't have to use any special settings when charging from 240V sources. You just plug the EVSE using the correct pigtail and the car will start charging at 240V. You also don't have to worry about charging at too high a current or rate since the EVSE will only draw a maximum of 12A whether it is plugged into a 120V or 240V circuit, and all 240V circuits can supply at least 15A.

NEMA 14-30 and 14-50 Adapter

The NEMA 14-50 receptacle is what large RVs plug into at campgrounds. The NEMA 14-30 receptacle is what modern houses have as their electric dryer plug (older houses have the NEMA 10-30, see below).

The cool thing about these two receptacles is that they can be handled with just one pigtail. To start with, buy a NEMA 14-50 male plug. I like this one since it can easily be modified to work with NEMA 14-30 receptacles too. Then buy a short 14 gauge or better extension cord (NOTE: a 14 gauge cord will only work for Volt/Bolt EVSEs, other EVSEs would need heavier gauge).

The NEMA 14-30 and 14-50 receptacles are similar and if we look at them side by side with the round ground pin on top we see that the only difference is that the bottom pin, which carries neutral for delivering 120V, is either straight or an L. For our purposes, all we need is a ground (top round pin) and the two 240V hots (the two side blades). We do not need to connect the neutral at all. And on the Camco 14-50 plug, it can easily be removed. And if you remove the bottom neutral blade, now the plug can be plugged into either a NEMA 14-50 OR a NEMA 14-30 receptacle. Pretty cool, eh?

To make the pigtail, cut off the plug end of the extension cord, leaving only the receptacle end attached to the 3' cord. Expose the three wires inside the cord (or pull them apart if it is a flat cord) and strip about 1/2" off the insulation exposing the copper wire. You need to identify which of the three wires connects to the round ground pin on the 120V receptacle. The only way to know for sure is to use an ohm meter. Using such a meter, test continuity between the round ground pin on the extension cord and the wire you think is ground. If the meter measures 0 ohms, then you've found the ground wire. Attach this ground wire to the NEMA 14-50 ground pin (the round pin). The other two wires on the extension cord go to either of the two side pins on the NEMA 14-50 (side, assuming the ground is pointed up).

VERY IMPORTANT: When you are done making your pigtail adapter, PLEASE attach a label that says something like: "ONLY USE FOR EV CHARGING". This pigtail will deliver 240V onto a household 120V receptacle which would fry any normal appliance that got plugged into it. So only use it for charging with your 240V rated mobile EVSE and NOTHING ELSE.

Background Information

Here is a forum thread that discusses this and why this works. Make sure that your Volt/Bolt adapter looks like this.

NEMA 10-30 and 10-50 Adapters

The NEMA 10-30 receptacle is what older houses have as their electric dryer plug (newer homes have the NEMA 14-30, see above). Don't confuse the NEMA 10-30 with the similar looking TT-30. See the Receptacle Identification page to see the difference.

To start with, buy a NEMA 10-30 male plug such as this one (pictured is the 50A variant, it also comes with the angled blade for 30A dryer). Then buy a short 14 gauge or better extension cord (NOTE: a 14 gauge cord will only work for Volt/Bolt EVSEs, other EVSEs would need heavier gauge).

The NEMA 10-30 is a three prong plug. The bottom right angle pin is the 120V neutral, and the two angled straight blades are the two 240V hots.

To make the pigtail, cut off the plug end of the extension cord, leaving only the receptacle end attached to the 3' cord. Expose the three wires inside the cord (or pull them apart if it is a flat cord) and strip about 1/2" off the insulation exposing the copper wire. You need to identify which of the three wires connects to the round ground pin on the 120V receptacle. The only way to know for sure is to use an ohm meter. Using such a meter, test continuity between the round ground pin on the extension cord and the wire you think is ground. If the meter measures 0 ohms, then you've found the ground wire. Attach this ground wire to the NEMA 10-30 right angle bottom neutral pin. The other two wires on the extension cord go to either of the two side angled straight blades on the NEMA 10-30.

VERY IMPORTANT: When you are done making your pigtail adapter, PLEASE attach a label that says something like: "ONLY USE FOR EV CHARGING". This pigtail will deliver 240V onto a household 120V receptacle which would fry any normal appliance that got plugged into it. So only use it for charging with your 240V rated mobile EVSE and NOTHING ELSE.

The NEMA 10-50 (often used in older homes for stoves) is very similar to the 10-30, except that the bottom non-angled blade is straight rather than a right angled blade. You can use the same NEMA 10-30 plug I used above since it comes with a straight neutral blade as well. Follow the same instructions as above for the 10-30 to make the 10-50 adapter.

NEMA 6- Series Adapters

The NEMA 6 series receptacles, 6-15, 6-20, 6-30, and 6-50, deliver 240V at 15, 20, 30 and 50 amps respectively. They are easy to make adapters for since they only have three pins, the two 240V hots and a single round ground pin.

To start with, buy a NEMA 6-series male plug such as this 6-15 plug, or this 6-30/6-50 plug (can be used as either a 6-30 or 6-50 depending on which blades you build it with, it comes with extra blades). There is no need for a 6-20 adapter since a 6-15 plug can plug into a 6-20 receptacle as well as a 6-15 receptacle. Then buy a short 14 gauge or better extension cord (NOTE: a 14 gauge cord will only work for Volt/Bolt EVSEs, other EVSEs would need heavier gauge).

To make the pigtail, cut off the plug end of the extension cord, leaving only the receptacle end attached to the 3' cord. Expose the three wires inside the cord (or pull them apart if it is a flat cord) and strip about 1/2" off the insulation exposing the copper wire. You need to identify which of the three wires connects to the round ground pin on the 120V receptacle. The only way to know for sure is to use an ohm meter. Using such a meter, test continuity between the round ground pin on the extension cord and the wire you think is ground. If the meter measures 0 ohms, then you've found the ground wire. Attach this ground wire to the 6-series plug round ground pin. The other two wires on the extension cord go to either of the two side blades on the 6-series plug.

VERY IMPORTANT: When you are done making your pigtail adapter, PLEASE attach a label that says something like: "ONLY USE FOR EV CHARGING". This pigtail will deliver 240V onto a household 120V receptacle which would fry any normal appliance that got plugged into it. So only use it for charging with your 240V rated mobile EVSE and NOTHING ELSE.

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