> Under certain special conditions, the device connects the fax machine > directly to the PSTN by means of an electromechanical relay that also > disconnects all ground-referenced SELV circuitry that is connected to the > fax machine at other times.
David, This is a "switch-through" application, as were the old electromechanical PBXs and KTSs. Hence, the device will have to meet all the requirements of CS-03/P68 in Canada and the USA, when "switched-through". You may have to provide evidence that the mechanisms used to switch the machine are such that it is unlikely that the device will do strange things such as half switching through, when it is not supposed to, and under those circumstances offer an unacceptable interface. Ciao, Vic
