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TF Instruments, LLC welcomes you to our website.

We figure you are looking for a 240VAC switch device for your electric vehicle (EV) charging because you already have an electric dryer 240VAC outlet as shown in the below picture.

Tired of straining the arm to unplug-then-plug your electric dryer 240VAC outlet to charge the electric vehicle ? Worrying that the good old 240VAC outlet may wear out ... ?

Perhaps you would like a switch device that can plug into your existing 240VAC outlet to time-share it between the electric dryer and the charging of your electric vehicle? One that is safe, reliable, and economical ?

You have come to the right place.

TF Instruments, LLC specializes in the design and manufacture of safe and reliable AC switch devices for 240VAC outlet load time-sharing purpose.

We offer a complete line of smart design and quality AC switch products.

But what exactly is "load time-sharing a 240VAC Outlet" and how is it done  ?

Answer : basically, it is to use the same existing 240VAC outlet for more than one electric device / AC load. It can be done safely by using the TFI-1xx automatic AC switch or the TFI-2xx manual AC Switch to select an electric device / AC load for use one at a time. With the TFI-2xx AC Switch, the user needs to manually move a switch while the TFI-1xx employs a fast microcomputer and solid-state electronics to constantly monitor the AC input at the higher priority (dryer) side then swiftly, safely and automatically switches off the electric device / AC load at the lower priority (EV) side whenever the dryer side is active. This precludes any chance of an overload condition and/or a fire hazard. After the dryer side is inactive for more than two minutes, the EV side is automatically re-connected to the 240VAC source for EV charging task.

Click here TFI AC Switch Set-up Examples for set-up examples.

Since the electric dryer is typically used for only 2 to 6 hours per week, the 240VAC outlet can, through time-sharing, be used for electric vehicle (EV) charging or any other work during the remaining hours of the week.

Time-sharing of 240VAC outlet is completely safe. On the other hand, "splitting" an outlet, i.e., using the same 240VAC outlet for two high current/power AC loads at the same time is NOT safe since it may lead to an overload condition and a fire hazard.

And what are the benefits of time-sharing a 240VAC outlet ?

Answer : After a homeowner buys one or more electric vehicle(s), they need to find a way to charge it/them at home during the hours when the utility rates are most favorable. Depending on the size of their house, their current electric usage and the electric panel (60A or 100A) of the house, the homeowner with an existing 240VAC that is already used for an electric dryer may have to upgrade the electric panel to safely add another 240VAC outlet to support an EVSE (EV supply equipment) Level2 for the additional EV charging need. Such upgrade can be costly and averages a few thousand dollars in most USA regional markets. Click link For Electric Panel Upgrade Cost.

Time-sharing an existing 240VAC by using TFI AC switches can safely eliminate this upgrade cost entirely (when the existing 240VAC outlet is already used for an electric dryer) or minimize it by allowing the homeowner to only upgrade minimally. For example, a house with a gas dryer and no existing 240VAC outlet can just add one 240VAC outlet at minimal cost, then use the 240VAC outlet time-sharing approach to charge several electric vehicles in one session.

The savings are more substantial when there are two or more electric vehicles to charge since the upgrade cost depends on the capacity of the new electric panel. Higher capacity electric panel to support several 240VAC outlets for multiple EVs charging in one session costs significantly more.

In summary, the TF Instruments AC switches can safely turn any 240VAC outlet into two or more (when connected in series) 240VAC outlets for load time-sharing purpose. This offers a simple, safe, and economical way to fulfill the EV home charging need.

Our products support all EV with EVSE (EV Supply Equipment) Level2 that plugs into 3-prong 10-30R or 4-prong 14-30R receptacles.

Please browse through to select the 240VAC switch that fits your need the most. Click here for Buyer's Guide.

Here is our product differentiation Why Choose Us?.

We hope our products will fill your need and help save your hard-earned money while we all do our part for a greener environment. (Our products are green since they enable the sharing / (re-)use of existing resources which can mitigate the need to upgrade / expand the power grid / infrastructure as home EV charging becomes more widespread).

Thank you for visiting our website.