First of all while selecting a transfer switch, ascertain the load of the generator which you have. Second, decide whether you need a manually operated transfer switch or Automatically operated transfer switch (ATS). Third, do you need an Open Transition or Closed Transition ATS. Fourth, ascertain the number of circuits & extra provisions needed. Fifth, find out whether the TS meets with the relevant safety regulations. Sixth, controls & accessories provided.
Of course, warranty offered is to be considered.
An open transition transfer switch breaks connection with one source of electricity before connecting to another one to avoid backfeeding.
A closed transition transfer switch makes connection even before transfer of power to the load in cases where zero interruption is desired.
A soft-loading transfer switch actively changes the amount of load accepted by the generator.
A static transfer switch employs semiconductors like Silicon-Controlled Rectifiers (SCRs) to transfer a load between two sources rapidly i.e., within a quarter-cycle of the power frequency.
Homes with standby generators may use a transfer switch for limited circuits or in total.
Different models are available, with both manual and automatic transfer.
Manual Makes:
Reliance, Gen Tran, Generac,Steel Products (SP), Briggs & Stratton, All Power America, Chilton etc.
Automatic Makes:
Generac, Kohler, Briggs & Stratton, Parallax, Siemens, Esco, Generlink, Datakom, APC etc.