The article explores techniques for implementing arithmetic operations in the system of residual classes (SRC). Examples of determination of positional characteristics of numbers which are presented in the residual class system are given. In particular, the determination of the rank of a number can be carried out in the dynamics of a computational process, i.e. without stopping calculations for the duration of non-positional operations of transferring numbers from the system of residual classes to the positional number system and vice versa. The method of determination of positional characteristic of non-positional code – rank of number in SRC is considered in the article. Examples are given to show that determination of the rank of number can be implemented without stopping the calculation process. This gives the opportunity to fully use the main feature of the RC, which is high-speed of performing arithmetic operations.