odyssey 3 alarm fault relay output?

hi there, i am in the process of connecting a second bellbox (texecom odyssey 3) to my alarm system. on the sounder there is a fault relay output. there is only 1 cable from the panel (8 core) which connects to the first sounder. i have ran an 8 core from the first sounder to the second. everything is connected apart from the fault relay output. the manual does not show how to connect it when using both sounders.

is it just a case of connecting the fault relay outputs in series with both sounders then connect to spare zone in the panel?

thanks in advance