Hello everyone, I am currently working on a ladder logic rung that involves controlling motor C4 based on conditions C1, C2, and C3. Attached is the ladder diagram displaying the current rung for your reference. I am looking to incorporate an additional condition into this rung: a contact from another output. The goal is for the motor C4 to either run if this new condition is 1 or not run if it is 0. I would appreciate your input on whether I am taking the correct approach. Should I include this new condition as a Normally Closed (NC) or Normally Open (NO) contact in the rung? Any guidance on the optimal placement for this contact would be greatly helpful. Please note that C4 and C5 share the same addressing. Thank you in advance for your assistance!
When deciding whether to add a new condition as a Normally Closed (NC) or Normally Open (NO) contact in the rung, consider how the switch is wired and the desired reaction. You can experiment with different options using PLC Fiddle to find the best configuration.
Insufficient information is available to provide a direct answer. In dealing with boolean logic, it is essential to understand the three primary operators: AND, OR, and NOT. The current logic can be represented as follows: IF (either c1 OR c5) AND (NOT c2) AND (NOT c3), THEN the value of c4 is set to 1; otherwise, it is set to 0. Karlsmith has suggested the addition of a new condition, cNEW, to the existing logic. According to Karlsmith, if cNEW equals 1, motor C4 should run; if cNEW equals 0, motor C4 should remain inactive. The interpretation of this statement may vary: it could mean replacing the existing logic entirely, adding cNew in series with the logic, or adding cNew in parallel with the logic to determine when the motor should run. More clarification is needed to understand the precise relationship between the new condition and the existing logic.
The description provided is unclear, stating that C4 and C5 have the same address which is not typical in PLC programming. Most PLCs do not allow for different symbols to have the same address. In this scenario, if C4 and C5 share the same address, it implies that C4 is latched in by C5, and will only unlatch when either C2 or C3 become true. On the other hand, if C5 has a different address, the condition is that C1 OR C5 are true, and C2 & C3 are false, then motor C4 runs. If either C2 or C3 are false, it will stop. To clarify this further, if C4 should only run when a new output is active and the existing logic is true, simply add a new contact in series with the top of the rung as a normally open contact.
"Geniusintraining recommends using PLC Fiddle to test how the switch is wired and how it reacts. Thank you for the response! I am looking to include a 'memory bit' that is a result of a set of conditions in another logic. When deciding between a Normally Closed (NC) or Normally Open (NO) contact in the rung, it is important to consider the relationship between the new condition and the existing logic. There are three boolean operators to consider: AND, OR, NOT. The existing logic can be summarized as IF (EITHER c1 OR c5) AND (NOT c2) AND (NOT c3) THEN c4 value is 1 ELSE c4 value is 0. Let's refer to the new condition as cNEW. The context of the statement may be ambiguous, leading to different interpretations. It could mean replacing the existing logic with a two-instruction statement or requiring both the existing logic and the new condition to evaluate to True for the motor to run. Alternatively, it may indicate that if ANY of the existing logic or the new condition evaluates to True, then the motor should run. Thank you for the comprehensive explanation and clarification of the possible scenarios. I value your assistance and will make the necessary changes based on your recommendations. I will provide an update after testing the program to share the outcome with you."
Is the new motor in operation functioning as an interlock system?
Hey, with the current information provided, I'd suggest including the command as a Normally Open (NO) contact. If you set it as NC, the motor would run when the condition is not satisfied (0), which is not what you aim to achieve. Regarding placement, place this new condition contact just before the motor C4 output coil in the rung. This way, the condition check will happen right before an attempt to activate the motor. But remember to double-check your existing logic to ensure no interference between this and other conditions in your ladder logic. Good luck with your project and keep us updated!
Based on what you've shared, adding the new condition as a Normally Open (NO) contact might be the most suitable approach. This way, when your new condition holds a value of 1, the circuit completes and the motor C4 will run. Conversely, if it's 0, the open contact will break the circuit, thus stopping the motor. As for the placement of this new contact, it largely depends on the specifics of your operation. However, typically a good start would be to place it in parallel if you want the motor to run under additional condition, else place it in series to stop the motor when the new condition is not met. It may require some trial and error to find the optimal placement. Always remember to properly address and document the new contact for future troubleshooting!
From the details given, your approach seems to be on the right track. If the motor needs to run when the new condition is 1, you may want to consider introducing this as a Normally Open (NO) contact. As for the placement, since C4 and C5 share the same addressing, the new condition should be placed parallel to the conditions controlling C5. This way, the rung will evaluate to true if either the previous conditions for C5 or the new condition is true, ensuring that both C4 and C5 are handled correctly. Be sure to carefully cross-check your logic to prevent any unintended operation.
It sounds like you’re on the right track with integrating that new condition! If the goal is for motor C4 to run when the new condition is 1, you should use a Normally Open (NO) contact for that output. Placing the NO contact in series with your existing conditions (C1, C2, C3) will allow motor C4 to run only when all conditions are met, including the new one. Just make sure to clearly label everything, especially since C4 and C5 share the same addressing—it’ll help avoid any confusion down the line! Good luck with your programming!
It sounds like you're on the right track with your ladder logic! If you want motor C4 to run when this new condition is 1, you'll want to use a Normally Open (NO) contact for that condition in your rung. Place it in series with your existing conditions (C1, C2, C3) so that all must be true for C4 to activate. If the new condition is false (0), it will open the circuit, preventing C4 from running. Just remember to keep an eye on the addressing for C4 and C5 to avoid any conflicts. Good luck, and I'm sure it will come together nicely!
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Answer: - To add an additional condition to control motor C4, you can incorporate a contact from another output. This new condition can determine whether the motor runs based on its state (1 or 0).
Answer: - The decision to use a Normally Closed (NC) or Normally Open (NO) contact depends on your specific requirements. A Normally Closed contact will allow the motor to run when the condition is not met, while a Normally Open contact will enable the motor to run when the condition is met.
Answer: - The optimal placement for the new condition contact in the ladder diagram depends on the logic flow and interaction with existing conditions C1, C2, and C3. Consider the sequence of operations and ensure that the logic is structured logically to achieve the desired control of motor C4.
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