The modbus node gives you back an array reply for the range of modbus registers you requested.
Its up to you to make calculations later and with the use of Buffer-parser to convert them to the correct type depending on the manufacturer.
See a post from Steve regarding the calculations he made in that example as to what registers to read and what offset to use.
1 register = 2 bytes = 16bits
32bit values need 4 bytes and from the device docs you'll see that you need to read two registers to calc. them.
