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Thumbwheel Switches

Terms for Configuration and Structure
Explanation of Common Terms

Output Codes


Thumbwheel Switches

+/- Dial Display ("-PM" Models)


It is possible to produce 06-type models (binary coded decimal code) that display "+, -, +...-" instead of "1, 2, 3...9". The model numbers used for this type of Switch are A7[]-206-PM and A7[]-206-PM-1. Below is an example of the A7BS-206-PM. The Switch's output terminal 1 and common terminal are used for binary output.


A7BS-206-PM Thumbwheel Switch


Thumbwheel Switches
Example of A7BS-206-PM
Thumbwheel Switches

Example of A7BS-206-PM

Stoppers are mechanisms for preventing the wheels rotating outside set ranges. There are internal stoppers that are set at setup and external stoppers that can be set as required at any time. For example, a wheel that normally displays any number in the range 0 to 9 can be restricted to the range 0 to 5 using a stopper.

  • Add -S[][] to the suffix, specifying the range in the blanks.
    •      Example: A7PS-203-S05
  • Units to which stoppers can be attached are the A7DP, A7D, A7BS, A7BL, A7PS, A7PH, and A7AS. Consult your OMRON representative for details on individual model numbers.
  • On the outside of the A7BS-[]-S is a Stopper Pin with which the user can make any setting.
  • The A7CN-2, A7CN-1, A7CN-L2, A7MD, and A7MA cannot be equipped with stoppers.


    • Example of A7BS-206-PM
    Thumbwheel Switches

    Note: The A7MD has special specifications (anode common). Be sure to connect the terminals with the correct polarity.


    The configuration for the A7MD-106-P-D is shown below.
    Thumbwheel Switches

    Note: The diode (DAP202K, made by Rohm) is installed inside the case.