Questions tagged [plc]
Programmable Logic Controller
202
questions
0
votes
0answers
52 views
Industrial Oven Control
I'm working on upgrading an ancient oven that we bought second hand, which came with almost zero documentation.
I have identified two fans one is exhaust fan and the other is a circulation fan.
Is it ...
0
votes
0answers
15 views
Sercos Bus Monitoring
I want to monitor traffic on a SERCOS bus that is controlled by a Schneider/ELAU C600 PACDRIVE
I have a profibus port on the C600 but don't want to impact scan time.
Is there a device/Gateway that I ...
1
vote
0answers
97 views
SPI data lines look identical, but results are different, how is that possible?
I have a golden sample system which consists of 2 devices communicating via SPI.
I swap one of the devices and bit bang the SPI to make it similar to the golden sample.
However the bit banged device ...
-1
votes
1answer
27 views
Hmi normally open or normally closed
Currently i am working on a new project for which im using Unitronics vision oplc ide .This is my first time using unitronics plc .
I have a doubt , while i'm using invertbit,would the object be a NC ...
0
votes
0answers
31 views
Product ID tracking in a sorter machine
I'm writing a PLC program (Q Series Mitsubishi PLC, GXWORKS 2 Software) for a package sorting machine.
The logic of the machine is the following:
Packages are induced in the conveyor. A barcode ...
0
votes
1answer
22 views
Industrial IO board ST X-NUCLEO-PLC01A1 - design features
For a project I want to buy an X-NUCLEO-PLC01A1.
So I studied the schematic and datasheets (CLT01-38SQ7)(VNI8200XP), but there are still some points that confuse me.
What is the purpose of D20 - is ...
0
votes
0answers
49 views
24 Volt system with 2 outputs. Convert to 12 Volt Outputs
What would I need to add to set up to get 2 outputs at 12 volts. Outputs are 0 and 1. I would assume relays.
Signal Outputs. For a 3 Position 12V Solinoid.
Micro 820 2080-LC20-20QWB
0
votes
1answer
32 views
Short Circuit in Allen Bradley Micro850 Output Headers
Unfortunately, I have discovered that the outputs 0 and 1, as indicated by my blue Sharpie marks, have continuity. I have inspected the circuit for hours, and cannot seem to find the source of the ...
0
votes
0answers
26 views
How to pass a DBWx-value 2 block-calls deep on Siemens S7-400/Simatic
I'm working on code that was transported from a Siemens S5 PLC to S7. The code works with an old FC(FC2 in the example) that uses a WORD-input called "BNR" to load/save data. When block FC2 ...
0
votes
1answer
39 views
pt100 RTD transmitters not working - two in a row - am I doing something wrong?
I just tried to use two different ones of these RTD transmitters with a pt100 probe (3 wire) with no success.
I am connecting the transmitter directly to a 4-20mA input on a PLC, as shown in the ...
0
votes
1answer
72 views
how to tell if this proximity sensor is NPN or PNP?
I have a proximity sensor without nameplate . I have done some tests that made me think it is a PNP Normally open .
is my assumption correct ? is there another method to know ?
TEST setup : Supply ...
0
votes
3answers
72 views
Zero crossing detector output to another optocoupler
I will use the configuration below to build a zero crossing detector to connect to a PLC.
I will change the output voltage to 24VDC and the correspondig resistor to 50K.
The problem is that the input ...
0
votes
0answers
27 views
Cold Reset STC125A60S2 PLC Board
I am working on these PLC Board: http://more-suns.com/product/html/?321.html but I cannot contact manufacturer. The fact is to have it programmed I have realized that I can only do it after a cold ...
0
votes
2answers
68 views
Thermocouple troubleshooting
I have a system error pop-up on an HMI of one of my machines. Since it only had a number, I tried to reach the manufacturer for the error code description. They said that this error usually is the ...
1
vote
1answer
33 views
Delay in turning on two different start buttons in Star/Delta starter on PLC
Currently I'm working on a university project based on Star/Delta Starter on PLC.
I wrote program using LD, that switches on the circuit with a motor rotating forward (of course with star/delta ...
0
votes
3answers
56 views
IO link sensors with PLC
This is probably a stupid question but I am new to IO link sensors.
When using IO link technology with a PLC (siemens s7-1200) can you connect devices that are not IO link sensors?
For example say I ...
-3
votes
1answer
56 views
What is the best way to store data from Modbus TCP? [closed]
What is the best way to store all data generated from Modbus TCP in SCADA? it is better to store it in a file or directly to SQL Server?
is data stored every second?
If it store in SQL Server every ...
0
votes
0answers
45 views
Level sensor Transmitter
I have a level sensor and transmitter(4-20mA standard) of Qidian Automation for sensing level of liquid in tank having capacity of 1000 litres. On transmitter it is displayed 0.516 when tank is half ...
0
votes
2answers
56 views
Driving a 12V-24V 20 ohm solenoid from a 24V 0.5A input signal
I had a question about trying to get a solenoid with 20 ohms resistance to power up from a 24V Power supply limited to 0.5 amps.
I tried connecting a 10 ohm resistor in series, to drop the driving ...
2
votes
3answers
167 views
Wiring a simple 24v DC light on an output terminal on a PLC
I am using a Micrologix 1100, part number 1763-L16BWA. I have been able to get the input side working, but can’t seem to figure out the wiring for the output side. I also have an 1762-IQ8OW6 extension....
1
vote
1answer
36 views
I need to understand the circuit diagram of a Klöckner Moeller relay output unit
I am working on the automation of an old servo driven feed system for a mechanical power press. I have come across these relay output units from Klöckner Moeller (machine make year 1980`s) pictures ...
1
vote
1answer
84 views
Using RS485 over CAT5e Foiled Twisted Pair (FTP)
I'm planning a system that has two sub systems that need to communicate with the PLC via RS485. The baud rates are 9600 and 19200 bps.
The cables are static (i.e. not moving) and placed inside of a ...
1
vote
0answers
36 views
EC and pH sensor in plc automation
I am working with automation using pH and EC sensors. Both are of 4-20mA communication standard. When at a time single sensor is placed in liquid(in 1000 litre tank) then everything works fine (...
0
votes
0answers
31 views
How to write a variable from firmware to a PLC address in OpenPLC
I'm using openPLC for my project and this requires sending data from the firmware to OpenPLC. More specifically, I need to send collected data from the embedded program in the firmware to PLC ...
1
vote
2answers
104 views
Max load on analog output
I am planning to connect an Omron ZL1-series 4-20 mA level transmitter to a 0-10V input on a PLC.
To do so, I have to convert the current to a measurable voltage by connecting a 500 Ω resistor to the ...
0
votes
0answers
72 views
Turn Node MCU into a PLC which is integrated Lora module for IoT application
I've built a PLC that supports Lorawan and Modbus protocol using Node MCU. I managed to make it possible with Modbus by using OpenPLC. Everything worked well apart from its limitation in the distance ...
1
vote
2answers
27 views
Testing the accuracy of a PLC current input module - economical approach?
I don’t want to suggest a particular brand or model so to discourage a good universal approach. But let’s say the DUT here would be your typical industrial PLC module, a typical 4-20mA SAR ADC based, ...
1
vote
1answer
75 views
What is the difference between these two ladder logic diagrams?
First ladder logic diagram:
Second ladder logic diagram:
I am trying to implement a toggle switch. On the rising edge of "Change", it should toggle "ToggleThis".
I thought the ...
0
votes
1answer
92 views
Rise time of 6N136 opto-coupler
I am trying to use below circuit for convert 24VDC high speed pulse to 5VDC pulse that can interface to a stepper driver IC.
I have used 6N136 opto-coupler and according to its datasheet it can handle ...
0
votes
1answer
41 views
Low power temperature monitoring
I'm trying to monitor the temperatures at various location inside and arround my house. So far, I used battery powered (18650 Li-Ion) ESP8266 chips with a DHT22 sensor. The ESP wakes up every 5 ...
0
votes
1answer
24 views
Removing STM32F4xxx based HMI from CANBUS puts the network in BUSHEAVY state
I have a CANBUS with 3 devices on it. A PLC (CAN IO 14+, HAWE), a HMI (Barth DMA-20) and a 6 button CAN enabled button panel (Greyhill).
The issue is, when I remove the display from the network (...
0
votes
2answers
456 views
TIA portal - failed to establish a connection
I'm using TIA portal siemens v15.1 for my project when i tried to upload the code to the plc this error pops up. Appreciate anyone can help me in this issue
0
votes
1answer
39 views
Simatic Microbox PC
I just started my research studies and part of it is based on an assembly line which uses a Microbox IPC427E for automation. However, I have never used a microbox before and only have some experience ...
0
votes
1answer
87 views
Regarding PLC and several input/ output modules
I have to use more than 40 servo motors and 20+ load cells using PLC. But the problem is that I have to use many I/o modules ( that is costly and hectic). Can I reduce the no of I/o modules by any ...
0
votes
3answers
756 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
44 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 ...
0
votes
1answer
32 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
32 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
89 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
73 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
50 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
72 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
54 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
162 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
132 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
40 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
110 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
66 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
56 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
50 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 ...
