What is the Difference Between a Hardwired EVSE Installation and a Plug-in Installation?
So you’ve done your research and decided on the electric car you’re going to buy, and you’re ready for the next big step: figuring out what kind of charging station to buy.
The first major thing to consider when getting a charging station is making sure you have a
safety-certified charging station and you have the capacity in your electrical panel to install a charging station. To assist you with investigating your panel capacity for safety, check out
our electrician locator tool for a list of licensed electricians near you.
The next consideration will be whether you purchase a hardwired charging station or a plug-in unit.
So, what’s the difference? Let’s start with the plug-in charging stations.
Plug-In EV Charging Stations
A plug-in EV charging station connects to power by inserting the supplied plug into a matching receptacle (outlet). Plug-in units don’t have conduit like hardwired stations, but instead have a
high-quality 240V supply cord that is 12 inches in length. This measurement includes the plug itself and is the longest plug length allowed per National Electric Code.
All ClipperCreek charging stations are safety certified by a Nationally Recognized Testing Laboratory and must meet the requirements of UL 2594 and National Electric Code Article 625. If a charging station is available with a supply plug length of longer than 12 inches the product is likely not safety certified. Visit our “EV Charging Stations: Staying Safe” blog to find out more about why safety certification is very important.
Before you purchase a plug-in model there are few things to consider about plug and outlet safety.
Plug and Outlet Safety
- For personal safety, the circuit breaker MUST be turned off prior to plugging in AND/OR unplugging 240V appliances (including EVSE).
- Residential 240 Volt plugs are specifically designed for occasional relocation, such as moving from one home to another. Most outlets are not rated for consistent plugging and unplugging.
- A dedicated NEMA receptacle (outlet) is highly recommended. NEMA outlets wear out over time particuarly when repeated insertion and removal of NEMA plug occur. It is recommended that plug-in EVSE remain plugged in.
- Check the receptacle to be sure it is not worn. A worn receptacle can cause the plug connection to overheat and become a fire hazard. Do not use a plug that gets excessively hot.
- Have an electrician verify all wiring to the outlet is correct and in compliance with local code requirements before connecting the EVSE.
- Do not use an EVSE with an extension cord or wall plug adapter. Plug the EV charger directly into the receptacle.
- Ensure that the EVSE is mounted to the wall or placed on a support so it does not hang from the receptacle. Receptacles are not designed to support the weight of the EVSE.
For more information on plug and outlet safety please review the manual for the model you are planning to purchase. Click here to view all ClipperCreek manuals.
Plug Types for EV Chargers
If you decide to purchase a plug-in charging station you will also need to decide on which plug type you will purchase. With 240V plugs / outlets there is no standard type which is why ClipperCreek offers a wide variety of 240V plugs with our charging stations to fit your needs. Some homes already have a 240V outlet and you can order the plug that matches what you already have! This allows you to simply mount the station and plug in to start charging your electric vehicle.
If you have a 240V outlet, but are unsure if ClipperCreek carries the matching plug type, please call us at (877) 694-4194 or email us at firstname.lastname@example.org. Our customer service team can help you determine what type of outlet you have and which electric car charging stations would be appropriate.
If you don’t already have a 240V outlet, you can have an electrician install a new outlet which matches the plug you purchase. Once the outlet is installed, simply mount the station to the wall, plug-in, and start charging!
Hardwired EV Charging Stations
Hardwired charging stations can typically be installed indoors or outdoors; check with the manufacturer. All ClipperCreek charging stations, whether they are hardwired or plug-in, are rated for installation both indoors and outdoors.
A hardwired station has three feet of flexible conduit coming from the top or bottom of the station (depending on the model) and service wires that come out of the conduit about six inches for easy installation into a junction box.
When it comes to installation, hardwired units are typically more permanent and are always recommended for outdoor installations as hardwiring the appliance provides a better and more weather resistant connection to power. They can be moved, but you’d probably need to have an electrician come out to uninstall and then reinstall the unit at your new location. With a hardwired station the supply power wires from the station will be connected directly to the power wires coming from the electrical panel (circuit breaker).
Outdoor EV Charging Station Installations
Hardwired charging stations are recommended for any outdoor installation and there are a few reasons for this:
- The 3 foot flexible conduit provides more installation flexibility than the 240V 12 inch (1 foot) supply plug.
- When installing a plug-in charging station outdoors you would typically be required by electrical code to have a “While-in-Use” Weather Proof Outlet Cover installed over the 240V outlet. These covers allow for the 240V supply plug to enter from the bottom which will require the 12 inch supply plug to make a 180 degree bend if the supply plug comes from the bottom of the unit (varies by model).
- With a hardwired charging station you generally do not need to have a GFCI circuit breaker in place whereas you would be required to have this for any 240V outlet used for an electric vehicle charging station per National Electric Code requirements.
- Level 2 (240V) charging stations are high power, continuous use devices and hardwiring will provide the best connection to power. This is consistent with other outdoor high power continuous use devices such as HVAC equipment, sprinklers, etc.
- Using a GFCI breaker to supply a charging station can result in nuisance tripping of the breaker during charging. The trip threshold for a standard U.S. GFCI breaker is 5mA which is relatively low for electric vehicle charging. For comparison, charging stations have 20mA GFCI protection built it. At the 5mA trip threshold you may experience nuisance tripping of the circuit breaker during charging due to noise on the line generated by the vehicle.
A plug-connected charging station must be installed close and to the left of the outlet. The image above shows how a plug-in HCS model could be installed outdoors. Notice the smooth, metallic Weather Proof Outlet Covering.
A hardwired charging station can be installed indoors or outdoors, but is always recommended for any given outdoor installations. Notice the conduit coming from the bottom of the hardwired HCS model and the ridged cord.