Depending on ATV type, for example ATV6000, ATV630, ATV930 allows connection of min 1 and max 6 PTC connected in series.
I this case with 6PTC if they are connected in star like:
EP1-PTC1-PTC2-STAR,
EP2-PTC3-PTC4-STAR,
EP3-PTC5-PTC6-STAR
EP means endpoint),
then only 4 PTCs can be connected: ATV(AIx)-EP1-PTC1-PTC2-PTC4-PTC3-EP2-ATV(COM). Star point and third rung with EP3 will remain not connected.
I this case with 6PTC if they are connected in star like:
EP1-PTC1-PTC2-STAR,
EP2-PTC3-PTC4-STAR,
EP3-PTC5-PTC6-STAR
EP means endpoint),
then only 4 PTCs can be connected: ATV(AIx)-EP1-PTC1-PTC2-PTC4-PTC3-EP2-ATV(COM). Star point and third rung with EP3 will remain not connected.