I have installed several generator transfer switches made for 6.5 kw . They are close to $400.00 with tax . A customer I have installed one for wants small 2.2 k gens installed on 2 other locations on property. The prob is the 6.5 kw switch is smallest for sale locally. I hate for the customer to have to buy two of these for small gens. My question is why cant several 3 way switches be used for this. The common goes to the load and one terminal to breaker and other terminal to gen . I have no doubt will work because have done it before on a camper and thats whats inside a tran switch. But im sure code says something about equiptment must be approved for application on trans switch ?