The delimiter is placed between all numbers to make them easier to read, however the converter ignores the delimiter and only sees a string of digits. Hence all hex numbers need to be 2 digits and all binary numbers 8 digits. Decimal works by assuming all numbers are between 25 and 255.
When converting to characters from dec/hex/bin anything below 32 will be set to 32 (space). Using a delimiter that contains any hexadecimal digits [0-9A-Fa-f] will cause strange things to happen when converting from characters/bin/dec as they convert to hex first. You have been warned!