No Trumpy. I could not find the answers for all. For example I don't know how they take service factor into account, the basis for continuous and non continuous operation(based on duration of operation). I noted one thing, for most of the times they use dual element breakers for branch circuit protections which give overload protection capabilities as well. Additionally they use separate overloads for all the motors above 0.37 kW(IEE 16th edition). Therefore the dual element breaker acts as a back up protection for the overload. Further if the motor consumes say 12 amperes they select the next(15A) breaker with type 3 (or Type D if BSEN) characteristics where their magnetic settings are around 10-20 times their ratings. Therefore those breakers are capable to be used for motor starting. Most of the breakers they use have dual elements and short time long time pickups can be adjusted. When the feeders or branch circuits are calculated what I have noted is, they derate for the ambient temperature correction, grouping, insulation correction. I could not find any article how they classify the motors based on their duty ratings and use the factors like 1.25(as used in NEC and Canadian standards). I appreciate If somebody could give me the hints.
