{"id":"click-drum-instruction-time-base","model_id":"CL171 Drum Instruction: Time Base","name":"CL171 Drum Instruction: Time Base","summary":"The Drum instruction simulates an electromechanical drum sequencer. It sequences through 1 to 16 steps and turns ON up to 16 physical outputs or internal control relays in a user-defined pattern. With Time Base selected, each step advances automatically after its specified Duration elapses, and a Completion Flag turns ON when the sequence completes.","study_notes":["Time Base advances each step automatically after the specified Duration has elapsed.","Time increments available for Time Base are milliseconds, seconds, minutes, hours, or days.","Current Step must be stored in a DS-type memory address; Elapsed Time in Step must be stored in a TD-type memory address.","Enable Jog Input adds a rung; an OFF-to-ON transition on the Jog input jumps to the next Step.","Load New Step Number adds a Step No Input rung; an OFF-to-ON transition copies the DS-type new Step Number to Current Step.","Outputs can be physical outputs and/or internal control relays; the number of configured Outputs should match Number of Outputs.","The Output Pattern grid has one cell for each combination of Step number and Output number.","The Output Address Fill Down button enters consecutive output addresses automatically; the Fill Down button helps enter time Durations quickly.","Example: Step durations are 10 s, 20 s, 30 s, and 40 s; C1 turns ON at completion; X002 resets the Drum instruction; X003 jumps to the step number loaded in DS2; X004 jumps to the next step."],"safety_notes":["Number of Steps is limited to 1 to 16.","Number of Outputs is limited to 1 to 16."],"sources":[{"url":"https://cdn.automationdirect.com/static/helpfiles/click/Content/171.htm","title":"Drum Instruction: Time Base","accessed":"2026-10-26"}],"verification":{"status":"source_checked","checked_at":"2026-10-26","values":31,"method":"llm_source_check"},"updated_at":"2026-10-26","type":"instruction","spec":{"language":"ladder","code":"Drum","group":"Drum","parameters":[{"name":"Base","description":"The Drum instruction operates on Time Base, Event Base, or Time & Event Base. For Time Base, choose the time increment: milliseconds, seconds, minutes, hours, or days."},{"name":"Current Step","data_type":"DS memory address","description":"Memory address where the Current Step number is stored."},{"name":"Elapsed time in step","data_type":"TD memory address","description":"Memory address where the Elapsed Time in Step is stored."},{"name":"Completion flag","data_type":"Control Relay (C bit)","description":"Control Relay assigned as the Completion Flag."},{"name":"Enable Jog Input","description":"Selecting Enable Jog Input turns on an additional rung that allows the user to jump to the next Step each time the Jog input transitions from OFF to ON."},{"name":"Load New Step Number","description":"Selecting Load New Step turns on an additional Step No Input rung that allows the user to jump to a specified Step. The new Step Number is held in a DS-type memory address. The Step No Input is edge triggered."},{"name":"Number of Steps","data_type":"1 to 16","description":"Determines the number of steps in the sequence."},{"name":"Number of Outputs","data_type":"1 to 16","description":"Determines the number of outputs available during the sequence."},{"name":"Outputs","description":"Outputs assigned for the sequence; they can be physical outputs and/or internal control relays. The number of Outputs should match Number of Outputs."},{"name":"Duration","data_type":"time duration","description":"Time Duration assigned for each Step. The number of Steps should match Number of Steps."},{"name":"Output Pattern","data_type":"grid","description":"Grid where each cell corresponds to a combination of one Step number and one Output number."}],"related":[],"standards":[]},"url":"https://machineschema.com/instruction/click-drum-instruction-time-base","license":"https://creativecommons.org/licenses/by/4.0/"}