Cheng USA T30 T-30 30Amp Transfer Switch

When I turn my inverter on it automatically switches to solar power. When I turn the inverter off (or it shuts down due to low battery or whatever) it switches back to grid power. It has worked flawlessly for over a year. However it is NOT an uninterruptable power supply. It takes a fraction of a second to switch and this will cause electronics to reset and the lights will flicker when it shifts. It has shifted my power (average load about 350 watts) almost every day for a year with no problems. Highly recommended.

just what needed

This switch is made to switch between shore power and the onboard generator seamlessly and safely. I used it to switch between shore power and a 2000 watt inverter, and it works seamlessly. As the inverter comes online and up to power the unit rolls over to that source without ever having both sources connected at once. This is important, since shore power can ruin an inverter.

Easy to install if you know what you're doing. If you don't, hire an electrician. I used this to automatically transfer my RV's 120v electrical source from internal generator power to external utility power, which is its intended use. It works as it should. Good product.

Works as described. Switches good. Easy to install.

I liked the price. All this stuff is from China anyway such that it's a crapshoot if the one you install is better than the one that failed which is also a Chinese import. I laud the uniformity. The only departure was the grommets but they're interchangeable/replaceable. The ad picture tells the story. If it doesn't match exactly look elsewhere. Mind the box, however. Cut sheet metal can be dangerous especially when repacking the wires. Wear gloves and keep the bandaids handy. Cheers!

If you have a WFCO load center in your RV, without making your own, this is the only game in town. That said it does feature a high quality transfer mechanism and the control board does allow option bypass for the 30 second cut over (ie generator stabilization period) if using another source such as an inverter. Plan your installation to permit easy replacement. This is not the case for me due to the location of my load center (near the ceiling above the reefer). Mind the hands while handling; there are some sharp edges that could be better finished. My theory on failure is it needs heat sinks and/or fans. It gets really hot in my installation location as well…

Hooked this up in my RV to separate the shore/portable generator side from the invertor side. Switches over nicely as intended and hasn't skipped a beat. Solidly built, rather rugged and while I haven't had it all that long, I would believe it would last quite awhile based on how it is built.

Attaches perfectly to (WFCO WF-8955PEC-B-LIS Power Center with Lithium-Ion Switch - 55A, Black) and shares the same space. I don't have an onboard generator so I connected shore power to the generator input on the ATS since this is the dominant input. I feed the ATS from my 400AH LifePo4 battery pack via a 3000 Watt inverter connected to the shore power input on the ATS. If I need to use my generator I simply plug my shore power cord into it and it is automatically dominant. It charges my batteries and runs everything in the rig as normal. It seems to me that this ATS is labelled with an onboard generator in mind. All the same, if I had an onboard generator and was able to connect to shore power, I would still expect shore power to be dominant to avoid running the generator????? Labelling aside, it is a perfect setup so far, instant switchover in my setup (turned off the delay since inverter power is instantly available) so nothing turns off or resets. I also have a 400 watt solar charging system when off grid and it provides charging along my WFCO setup. Just remember - you must to turn off the converter/charger breaker to avoid charging your batteries with your batteries. :) Edit: Still going strong. To eliminate the need to turn on/off the breaker for the charger function - I simply connected the AC input for the charger to the shore power input inside the transfer switch to ensure my batteries get charged any time I connect. I included a fuse able link to protect the circuit.

Facile à connecter et fonctionne très bien!

This switch appears well made and is what I needed for my lifepo4 / inverter conversion on our travel trailer. I ran into a problem with it as it is primarily made for a generator setup. When I connected it as described and turned on the inverter it tried to charge the battery from the battery which doesn’t really work as it makes a loop in the system and will eventually run the battery down. I looked on google and youtube for clarity on this and the best advice came from a previous Amazon reviewer who had the same issue. You need to disconnect your CONVERTER input power from the circuit breaker and re-route it to the SHORE POWER input on the switch with a 15 AMP fuse so that it cuts the power to the CONVERTER when the INVERTER is switched on. This works well and everything plays happily together. WFCO should clarify this on their instructional videos as I am sure there are a lot of RVers who are upgrading their units for off grid camping with solar panel systems and leaving the generator at home.

Very simple to install and works as it should.

came fast works great