r/PLC 16h ago

Customer Demands

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77 Upvotes

Customer demanded everything be in 0.75mm² (18awg)

🤨😳🥺😭😠😡🤬


r/PLC 2h ago

Structured Text

76 Upvotes

I have to admit, I was wrong multiple times on this sub. I have been writing a program in ST on a Codesys platform the past week, cause that's what my customer wanted. ST really is the superior programing language... I'm sorry for doubting all of you nerds, I have joined you in the autism. I need not explain myself, if you know, you know. I am prepared to be downvoted by the non-believers and uncultured.


r/PLC 21h ago

Programming Question: Why are my outputs firing together?

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18 Upvotes

I have been working on a Click PLC panel for a project where I’m filling tanks and moving water with a fill valve, a pump and a drain valve. I’m self taught, built the entire panel and am so close to perfect, and I have everything working in the PLC cabinet (relays, indicator lights, inputs all work) but I’m stuck on the very last detail I need to make this right. Currently my only issue is that my output for my fill valve and my output for my drain valve turn on and off at the same time. Pics show my addresses, data sets and the logic. Can anyone take a look and see what I’m missing here?

Order of operation on input button push:
1) drain valve on tank 2 closes, full light turns on
2) fill valve for tank 1 opens for 30 seconds, closes
3) pump comes on after waiting 10 seconds and stays on for 25 seconds to move water from tank 1 to tank 2, shuts off
4) after 40 seconds the drain valve opens back up (ready light comes on) and drain valve stays open until the button is pushed again


r/PLC 8h ago

PLC jobs & classifieds - Sep 2026

8 Upvotes

Rules for commercial ads

  • The ad must be related to PLCs
  • Reply to the top-level comment that starts with Commercial ads.
  • For example, to advertise consulting services, selling PLCs, looking for PLCs

Rules for individuals looking for work

  • Don't create top-level comments - those are for employers.
  • Reply to the top-level comment that starts with individuals looking for work.
  • Feel free to reply to top-level comments with on-topic questions.

Rules for employers hiring

  • The position must be related to PLCs
  • You must be hiring directly. No third-party recruiters.
  • One top-level comment per employer. If you have multiple job openings, that's great, but please consolidate their descriptions or mention them in replies to your own top-level comment.
  • Don't use URL shorteners. reddiquette forbids them because they're opaque to the spam filter.
  • Templates are awesome. Please use the following template. As the "formatting help" says, use two asterisks to bold text. Use empty lines to separate sections.
  • Proofread your comment after posting it, and edit any formatting mistakes.

Template

**Company:** [Company name; also, use the "formatting help" to make it a link to your company's website, or a specific careers page if you have one.]

**Type:** [Full time, part time, internship, contract, etc.]

**Description:** [What does your company do, and what are you hiring people for? How much experience are you looking for, and what seniority levels are you hiring for? The more details you provide, the better.]

**Location:** [Where's your office - or if you're hiring at multiple offices, list them. If your workplace language isn't English, please specify it.]

**Remote:** [Do you offer the option of working remotely? If so, do you require employees to live in certain areas or time zones?]

**Travel:** [Is travel required? Details.]

**Visa Sponsorship:** [Does your company sponsor visas?]

**Technologies:** [Required: which microcontroller family, bare-metal/RTOS/Linux, etc.]

**Salary:** [Salary range]

**Contact:** [How do you want to be contacted? Email, reddit PM, telepathy, gravitational waves?]


Previous Post:


r/PLC 2h ago

When to use Managed Network Switches vs. Unmanaged

5 Upvotes

Hello, I'm a bit of a noob when it comes to this level of networking so looking for some help.

I have a project coming up with an Allen Bradley PLC with 5 AENTR IO racks in their own remote panels, 60 VFDs and 10 Modbus/TCP devices. I assume at this point I would need a Managed switch/switches to help deal with the traffic. All the VFDs will be setup with explicit messaging and the Modbus/TCP will be the built in AB AOI.

My main question is how important is it to have a managed switch in this instance? What would be the possible downfalls on going completely unamanged? On previous jobs and at other factories I've seen similar setups with nearly as many connections with all unmanaged switches and things seemed fine even after several years.


r/PLC 2h ago

Schneider PacDrive to AB L81

4 Upvotes

Looking for insight/suggestions. We have a customer who has a schneider PacDrive LMC201C currently running their system. They want to eventually get rid of it completely and switch to the AB. However they want to do it in a phased approach. So Phase one is replacing their current HMI software with Ignition. But we need to duplicate the aprox. 2300 tags the current HMI is using over in the AB plc. Which means you need a data connection from the Schneider to the AB. How would you recommend doing that? In later phases we would be stripping control from the schneider and start controlling from the AB.


r/PLC 14h ago

Intrinsically safe barriers.

4 Upvotes

I’ve got a project coming up which requires around 15 intrinsically safe barriers for equipment in a hazardous zone. Some are digital outputs and some 4-20ma.
What’s the best way to do this, would you have 15 individual barriers or is there a better solution?


r/PLC 8h ago

Alguien sabe qué sucede

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3 Upvotes

Es mi primera vez trabajando con este variador de LS electric, referencia LS-100 ya leí el manual como 3 veces y no encuentro el error o si falla algo más


r/PLC 4h ago

Jogging with keyboard input in Tia Unified V20

2 Upvotes

I want to jog a portal forward, backwards, up and down by pressing the corresponding button in the HMI when opening a screen in pop up. To do this faster i want to couple these buttons to the keyboard input z,s,q and D using the "hotkey" function. Apparently this does not work because i defined the jog by setting it on "press" event and resetting it on "release" event. The hotkey only works with the "click left mouse button" event (why Siemens...). But then the bit stays high... using the "press/release key" events also does not work because the botton must first be "focused" or something. I have not found a way to make this work, i think i have to script this but i have not much experience with that. Can somebody help me going in the right direction.


r/PLC 13h ago

Allen-Bradley 1734-AENTR + Spectrum Controls 1734sc-IE4CH showing Connection Request Timed Out (16#0204)

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1 Upvotes

Hi everyone, I’m troubleshooting an Allen-Bradley POINT I/O system and I’m stuck with a communication issue.

Hardware:

Allen-Bradley 1734-AENTR Ethernet adapter

Spectrum Controls 1734sc-IE4CH 4-channel HART analog input modules

Controller: 1769-L18ER-BB1B

RSLogix 5000

The AENTR is configured with IP address 140.168.0.165.

Initially, the AENTR had communication issues. After a power cycle, the AENTR LEDs are green and the device responds to ping. I can also access its web interface through the IP address.

However, Studio 5000 still shows the I/O modules as Faulted.

The main error I’m getting is:

16#0204 Connection Request Error: Connection request timed out

For example, one of the 1734sc-IE4CH modules shows this error under the Connection tab.

The physical AENTR shows:

Module Status: Green

Network Status: Green

PointBus Status: Green

System Power: Green

Field Power: Green

The 1734sc-IE4CH modules also appear powered, but Studio 5000 still reports them as faulted.

I also tried:

Power cycling the complete POINT I/O system

Using Reset Module from Studio 5000

Refreshing communication in Module Properties

Checking connectivity with ping

One thing I noticed is that the physical Spectrum Controls module has Series A / Rev C markings, while the Studio 5000 module definition shows:

Series: A

Revision: 1.001

Electronic Keying: Compatible

Connection: Data

Data Format: Analog with HART

Should I be changing the module revision/AOP configuration, or is this revision unrelated to the hardware Rev C marking?

What would be the correct way to troubleshoot the 16#0204 Connection Request Timed Out error when the AENTR itself is pingable and its LEDs are green?

Any help would be appreciated. Thanks!


r/PLC 14h ago

ABB ControlMaster CM15/30/50 Password Reset

1 Upvotes

Hi,

Does anyone know how to reset the Basic and Advanced level menu password for ABB CM15, 30 and 50 process controllers?

The menus are password protected, which means no new configurations can be uploaded or downloaded. This also means the password reset menus are unavailable.

I have access to the mainboards, but I don't see any jumpers or switches for a factory reset.

Happy to lose the existing config if it comes to that as I can load a backup, but without advanced menu access that won't be possible.

Nothing in the manual or on the ABB website about this situation either.

Thanks.