Questions tagged [plc]
Programmable Logic Controller
171
questions
1
vote
0answers
16 views
Electromagnetic Interference and Compatibility? [closed]
What does it mean for a device (like a controller) to have an EMC < 150 V/m?
0
votes
2answers
47 views
Communication between PLC and Arduino using IO-Link
I have a small device based on an Arduino and I want to send some data to a PLC that has no RS232 port but can have an optional IO-Link master card. I looked around but found no info about Arduino and ...
0
votes
1answer
27 views
Drive stepper motor with potentiometer in Siemens PLC
It is difficult for me to drive a stepper motor with potentiometer (position stepper motor with position potentiometer).
I've done program, to see the value from potentiometer with NORM_X.
I am using ...
-1
votes
1answer
51 views
Interfacing I2C with Siemens PLC [closed]
I have a Siemens S7-1200 PLC. Is there a good way to interface with an i2c sensor? I found that SIMATIC IOT2020 has an i2c extension board. But then I don't understand how to interface the SIMATIC ...
0
votes
1answer
20 views
STEP7 MICROWIN PLC Ladder Diagram
I draw like the first figure in the program, but when I save the program it automatically becomes the second shape. Do the two mean the same thing?
0
votes
1answer
28 views
How can I cycle through 4 LEDs with Timer Off Function (TOF)?
I have 4 LEDs that need to be turned on and off sequentially and cyclically. This is my code from code warrior:
...
1
vote
1answer
62 views
Exactly what is an RTU (Remote Terminal Unit)?
I find the Wikipedia article and other sources ambiguous and I find that the definitions are so broad that I don't know how and when to use the term "RTU". I would like to figure this out because I ...
0
votes
1answer
38 views
TLP LogixPro PLC Simulator
This is my second day of learning PLC online. I am doing a simple ladder diagram, and I came up with the following diagram:
The process I have in mind is as follows:
As the switch is closed, the ...
0
votes
2answers
49 views
How to convert high impedance / ground output to 24V / ground output
My background is from software development so please forgive my ignorance. I have an Adam 6156EI device I can control via Ethernet, it has 16 digital outputs. When I programmatically set an output ...
1
vote
1answer
66 views
Control Board with simple logic
We are using an old electrical system in industry. My task is to digitalise it. As i saw, PLC is too expensive and large scale for our operation. Also, microcontroller needs programming which makes ...
0
votes
1answer
51 views
what is the logic behind these ladder lines
I have a ladder diagram for timing porpose.(keyence KV-24DR)
some instructions are repeated many times but I dont understand what are these for.
can anybody help me?
the confusing thing is that the ...
0
votes
2answers
48 views
A very basic question about PLC field input switches
Below shows two simple ladder logic examples written for a PLC:
As far as I understand, the -| |- and -|/|- above are the symbols we write for the PLC not the actual input switches.
But we also need ...
1
vote
1answer
63 views
Creating ladder PLC logic using force inputs and outputs
I am currently using Allen Bradley PLC and RSLogix Micro to program it. The problem is:
Create a ladder logic diagram for the following problem in which pump #1 and pump #2, alternately or
...
0
votes
1answer
36 views
E3JK-R2R3 wiring
Hi, this is E3JK-R2R3, brown and blue connect to power supply. I wanted to know is it either black or brown connect to +load and the white connect to 0V?
If is it so, I don't see the electric flow.
1
vote
1answer
41 views
What do the letters and numbers mean in the addresses of Allen-Bradley PLCs?
I am using Allen-Bradley Programmable Logic Controllers. And using the Logixpro as a simulator.
In PLC we are talking about counters, timer, math operations( addition, subtraction, greater than, less ...
1
vote
2answers
35 views
Storage bit in OSF and best way to detect falling edge
I was looking for a way to detect falling edges and I encounter two ways:
|--XIO---ONS------------OTE--|
and
|--XIC------------------OSF--|
|--OSF.OB---------------OTE--|
My colleagues told me ...
1
vote
0answers
48 views
Connect DC/DC Conv Isolated Ground
I'm developing a modular equipment device aimed for industry, very similar to a PLC in terms of electronics. For all field interfaces I am using isolators and ESD protection for robustness and to pass ...
1
vote
1answer
37 views
Choosing controller/processor when real time feedback control system is required
Currently, I am planning to work on a system, in which we will be gathering the data from the multiple sensor for more than 15 parameters, based on the sensor value we will be controlling the ...
0
votes
2answers
77 views
A question about PLC architecture and ladder logic
I guess a PLC is programmed and run by a micro-controller at its centre.
But normally we use C language to program micro-controllers.
When we program PLC, is the ladder logic first converted to C or ...
0
votes
1answer
150 views
Interfacing 24VDC output with 5V TTL input
I have a project which requires me to interface a 24VDC output module (PLC) with a rather outdated 5V TTL input module.
From the schematics of the old module I can draw the conclusion that it uses +...
0
votes
1answer
17 views
Access device commands on Lenze 9400 Highline driver via Twincat3
I want to access the device commands on a Lenze 9400 Highline driver via CANoverEthercat(Twincat3). Is that possible and how can I do it? Specifically, I want to access the Device command 51: Identify ...
0
votes
1answer
140 views
JL1N PLC re-purposing for home automation
I own a JL1N-20MR (supposedly FX1N-20MR clone) based on STM32F103RCT6 CPU.
I figured that I might be able to re purpose this PLC for home automation by altering it's firmware to use something more ...
2
votes
2answers
191 views
Open source IO-Link
I have been looking at designing a solution around an IO-link master.
Does the IO-link Consortium allow for open source implentations of both the master and slave?
The documents online seem to give ...
0
votes
1answer
56 views
fully operational PLC with old pc using parallel port for inputs and outputs
hey there I am looking all over the internet for something like an OS (operating System) or either a software that can be programmed as we program a PLC. and for inputs and outputs we use parallel ...
-1
votes
1answer
36 views
How to controll position of a FeeTech FS90 RC Servo motor using a Mitsubishi FX5U PLC?
I want to control the position of a FeeTech FS90 RC Servo motor using a Mitsubishi FX5U PLC. The datasheet for the FS90 can be accessed through this link: https://www.pololu.com/file/0J1435/FS90-specs....
0
votes
1answer
42 views
Handling cyclic and acyclic UART messages
I'm looking into designing an IO-Link slave on page 35 of the IO-Link spec they mention Communication Channels. I have received an IO-Link device stack from TEConcept (ST/STM IO-Link partner), I ...
0
votes
0answers
30 views
Update an Automation Direct PLC Program without DirectSoft?
I tried to find an answer on the internet, buy didn't have any luck searching. I'm fairly new to PLC programming/development (Android/iOS guy, been doing PLC work for the past ~year off and on).
I ...
0
votes
1answer
81 views
PLC ST programming
I have a mathematical model of two dynamical systems which I need to implement in PLC. But I don't know how to implement differential equations in structured text language.
Any suggestions on that ...
0
votes
2answers
66 views
Connecting PLC with sinking output to PWM analog converter
I am using this pwm converter with this PLC. The PLC digital out is sinking transistor type.
I changed the pwm converter jumper switch to 24V and connected +24VDc from PSU to PWM terminal and one of ...
1
vote
3answers
58 views
Trigger PLC multiple times with delays
I am brand new to PLC's (don't even have a single device in use yet), but I have been programming for more than 20 years and haven taken classes in electrical controls, so I understand machine logic ...
1
vote
1answer
74 views
How to Test Allen Bradley PLC Analog Output Scaling?
I have an Allen Bradley ControlLogix 11756-L72S PLC with a 1734-OE2V 2-Point Analog Output card connected to a SMC pressure regulator that takes a 0-10 V input signal to set the pressure setpoint.
I ...
0
votes
1answer
37 views
4-20mA PLC analog output ground referencing for other devices
I'm currently using a PLC to control an induction heating coil.
I'm using a chinese induction driver that allows 4-20mA PID input. This device runs off standard australian 230v AC 50hz.
I've ...
1
vote
0answers
55 views
Why hasn't the industry standardized sink/source according to sensor/plc component type?
I know quite enough to understand how sink/source works when connecting sensors and PLCs, as well as how it works concerning the electronics components and circuit diagrams. What I don't understand is ...
1
vote
2answers
127 views
24V signal to drive led
I have a PLC which gives 24V DC output. I would like to drive an external LED using 24V.
Is this the correct way to drive an led?
Which is the right method let me know any changes needed.
simulate ...
0
votes
1answer
128 views
Help me choose the communication protocols that I need
I am developing an industrial sensor using a sensor IC and an ARM MCU which communicate via I2C. The data size is 3 bytes. Because the environment in which the sensor is located is harsh ( high ...
0
votes
2answers
181 views
Splitting 0-10V Analog signal from 1 AO to two different set of Ventilators to regulate speed?
Is it possible to take 0-10V signal from analog output and split it in parallel to two different Analog inputs ..to regulate speed of two different sets of ventilators? Or do i need some special ...
0
votes
2answers
142 views
How to connect multiple sensors to single PLC input?
Hello. I have a scenario where I have multiple PNP "error signal" from several sensors (let's assume 3 for now). If the sensor output is HIGH, then there is error. If the sensor output is LOW, then ...
-1
votes
1answer
346 views
In practical, what really is a memory word in PLC?
I came across some plc code (structured text) being used in an industrial company. When I asked the question, I got a blurry answer. However, what I picked up is that it has something to do with the ...
3
votes
1answer
62 views
What does the % symbol mean on plc addresses?
I've seen contacts assigned with a % symbol on ladder diagrams and plc structured text. For example a normally open start button would be %I1.02 and a coil would be %Q5.3
I understand the I and Q is ...
1
vote
2answers
74 views
Sensor to focus a robot on a welding line. (PLC robotics)
I'm searching for a way to recognize a welding line in an area. When the line is recognized, a small robot needs to follow the line.
I searched the web already and spoke with some sensor suppliers. ...
0
votes
2answers
86 views
PLC ladder-logic equation stabilization
I have worked with PLCs in the past. Now, I'm working with devices called 'vital-logic controllers'. The vital logic controllers are similar to PLCs, but I'm wondering about a subtlety of how the ...
0
votes
1answer
79 views
How should I match the impedance?
I have a problem for getting the 4-20mA input via 1769-IF8 I/O module. My field device is in good condition, but my AI card doesnāt respond. When I have been browsing about it, most of them said, the ...
0
votes
1answer
19 views
Unable to access the module error while trying to simulate a simple PLC Lad program
I am learning PLC and trying to simulate a simple program on Schematic Manager. But I'm having this error that says ...
0
votes
1answer
57 views
When using mA on analog devices, does the other wire go to 0V or Earth?
On the Schneider analog input module (link) we have IC, IV, IS, 0V and Earth terminals for a single channel.
I've seen people connecting the signal wire from a transducer to the IC terminal and the ...
0
votes
2answers
132 views
LED Matrix Light Leakage
I am controlling a 6x6 matrix of LEDs using a PLC with sourcing outputs and sinking outputs (24V). However, there is an issue with current leaking through to other lights.
For example, in the ...
0
votes
3answers
123 views
Why is there a negative value on the scada when the analog input wire is disconnected from a field instrument?
I'm an apprentice electrician at an fmcg company.
I've been seeing a trend recently, at the plant, where the scada actually reads a negative value instead of zero when a field device such as a ...
3
votes
1answer
145 views
Legal for trade weighing using a PLC
We have a project where we need to weigh product material for selling to customers. This is a project installed in Europe.
This is an industrial product line performing material manufacturing, ...
0
votes
1answer
76 views
PLC writing Software [closed]
I wanted to create my own PLC and PLC supporting software.
I would like to know how to get started.
Is there any software available to create background software?
What is a recommended ...
0
votes
1answer
74 views
Amplifying Current from 0-20mA to 3A
I would like to drive a pump with a PLC. The PLC generates analog output signal of 0-10V with 0-20mA and the pump runs at the same voltage but 3A current. Is there any solution to this problem?
Thank ...
0
votes
1answer
110 views
PLC hardware interface for BCD input
I am looking into designing a data converter that must provide data from a Scale (usually referred to as an indicator) to a very old PLC that only accepts data in BCD.
The current device that does ...
