1. 双击OB1，出现30：503和34：175错误。（30：503）There are no parameter and local variable names available because their des cription is not available or cannot be assigned。（34：175）The opened block does not contain any symbol information。
这两个错误没关系的,因为不是源程序，上载上来的所以丢失符号。复制源程序块显示就对了，不会影响程序的执行的。
使用FB2要用NCVAR软件做个连接的，并注意以下：
FB 2 can read NC variables only if basic program parameter NCKomm ="1" has been set (in
OB 100: FB 1, DB 7). The call is permitted only in cyclic program OB1. An assignment for all
parameters with Req = 0 is also permitted in OB 100.
When channelspecific
variables are read, only variables from one and the same channel
may be addressed via Addr1 to Addr8 in a job (FB 2 call).
In areas V and H, different logic axis numbers must not be assigned in one job. (Failure to
observe this rule results in Error:= TRUE, State:= W#16#02).