petey are you saying that this wire can't hanlde the 120 volts or that it is just not compatable with the standalone smokes?
The cable is intended for use in a power-limited system. A residential 120 V 15- or 20-A smoke detector circuit is not a power limited circuit. I think some strobe circuits using the teflon cable are 70 V at maybe 1 A, and the annunciator circuits I think are 24 V. Don't quote me, it's been a while since I have touched any fire alarm. But regardless, on a 120 V branch circuit, that is not the cable to use.