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GE Integers, ZCL, Jump Commands. MAIN 222 Industrial Controllers. Jump and MCR sometimes known as a ZCL. Master Control Relay aka Zone Control Logic. Used in pairs to create a zone. Nonretentive outputs can be turned off Retentive Outputs will retain their state.
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GE Integers, ZCL, Jump Commands MAIN 222 Industrial Controllers
Jump and MCR sometimes known as a ZCL Master Control Relay aka Zone Control Logic. Used in pairs to create a zone. Nonretentive outputs can be turned off Retentive Outputs will retain their state. Thus –()- output will go low and –(/)- will actually have an output on Drives all of the logic in between zone high even though power is “turned off” Safety issue maintains contacts without energizing them Works only in the forward direction Must have an end MCR zone
Examples of MCR • Classic Examples include: • Holding a PLC until a recipe loads • Waiting for an action at a prior point of a system to complete then continue
Jump • Jump Command is similar to MCR • However, Jump completely jumps through a section of programming • We can have multiple programs functioning and only let one function • Different from an MCR logic will not execute with negative logic. (see examples from Lab) • Jump commands must to addressed • A name must be associated with a Label • Each Jump must have the same name as its label • There must be an end jump LABEL • There has to be an area of the jump to get to • However, it can be forwards or backwards combatable • Can be multiple jumps • Jump verse Jumpn • Are the same function except jumpn is more used for all GE types • Jump seems to be used for more advanced GE series PLCs • Jumpn means jump within a nested PLC logic
MRC JUMP Handout • Notice MCR and ENDMCR • EXECUTE without power • MCR has not outputs • Jump needs a label • The label corresponds to the jump command
BLOCKS • Blocks are the PLC logic • GE uses blocks to identify a written logic area • Notice on the right hand side of software package there is a block • It is one section that makes up the file of the program you are writing • We can use a multitude of blocks to do accomplish a lot • Example: Trimming assembly • Block one drives the conveyor system • Block two drives the cutting sequences • Block three drives raw material tanks and goods bins
Always on function • The always on function is a necessity for the 90micro PLCs. • It is for the Counter and Timer Operations • It is not necessary for the GE ADD MOVE or COMPARE functions though it will not hurt if they are in either.
Add Integers • This command will add two integers, numbers and places the stored value in Q • In example from handout • %I1 causes %R2 to increment up 1 • It is added to %R2 • The output is %R3
Using Add Integers Parking Lot Example • Using the up down counter was ok in solving the problem. Ok it was all that we had • Using 1 address %R1 we can increment up or down • To do this we need to initially set the • IN 2 • Why is IN 2 set the way it is? • Notice the Full Parking Light is on when what condition occurs?