Questions tagged [plc]
Programmable Logic Controller
279
questions
0
votes
1
answer
54
views
Meaning of nom. voltage for terminal blocks
If the nom. voltage of a terminal block is i.e. 500 V, will it still function properly with only 24 V? For example this one: PT 1,5/S-QUATTRO - Feed-through terminal block
For a project I need ...
2
votes
1
answer
140
views
Incremental Encoder problem
I have a problem is that it is not possible to specify the direction of rotation in the encoder. Refer to it as in the attached picture.enter image description here.
The problem with the selection is ...
- 21
0
votes
1
answer
432
views
Right Way to Step Down a PWM Signal
I need to control 4 servos using a PLC that operates with 24V. The problem is that servos use only 5V. To accomplish this, I built a simple circuit using some 7805 and a large 1000 µF capacitor to ...
- 103
0
votes
1
answer
285
views
How can I improve my ladder logic diagram of a vending machine?
I am trying to create a coffee and tea machine using a ladder logic diagram. There are small, medium, and large sizes. This is where I am now:
Can you give me any ideas or corrections on how to ...
1
vote
0
answers
330
views
How does the incremental form of the PID controller work?
I have a question regarding the features of the so called incremental (velocity) form
of the PID controller. As far as I understand this form in correct manner it can be
described via this pseudocode
<...
- 1,113
0
votes
3
answers
301
views
Split supply from 24V power supply using uA741 opamp
I want to connect a 0-3V analog sensor output to the 0-10V analog input of a PLC.
In order to avoid losing resolution, I have amplified the sensor signal using a non-inverting amplifier circuit (based ...
- 407
5
votes
4
answers
547
views
SPI signal noisy when contactor switches
I created a Raspberry Pico based PLC board which worked perfectly alone, however once I placed it into a distribution box and started switching a fairly large (7.5kW) contactor, the on-board seven ...
- 61
1
vote
2
answers
629
views
How to improve ADC reading accuracy from 1mV to 0.1mV or better
I want to read a DC voltage from a battery with 0.1mV resolution or better and send the value to a PLC based in Arduino Mega. I selected an ADS1115 (datasheet here) which has enough resolution to do ...
- 407
2
votes
1
answer
247
views
How to calculate the cut-off frequency of a software average filter
I want to read the voltage of a battery using an ADC connected to a PLC. The signal oscillates a bit and I want to smooth it. The ADC samples the signal at 860 samples per second and stores it in ...
- 407
0
votes
0
answers
212
views
PLC output optoisolation with mosfet output
I'm wondering if this circuit i've made is correct.
Basically i want to separate PLC transistor outputs from loads.
I need 500mA output current for LEDs but also for relays etc.
PLC and loads are ...
- 1
1
vote
0
answers
63
views
Is it good engineering practice to share two different 24 VDC SMPS's neutral wires?
Is it good engineering practice to share two different 24 VDC SMPS's neutral wires?
I work in manufacturing with Toshiba extrusion machines which are controlled by PLCs. Our management wants to add a ...
- 19
0
votes
0
answers
85
views
Can I read the voltage (MCU ADC) with an isolated power source by opamp inputs?
I made a conceptual design to read an industrial 2- or 3-wire temperature sensor with a single 3-connection terminal.
I used an opamp in differential mode to read two terminal connections which are ...
- 343
0
votes
1
answer
464
views
24V I/O (PLC) to 3.3V interface with opto and PCF8574
I am more of a software guy, and I want to make sure my design works before sending it off to fabrication.
I need to interface with 24V PLC I/Os. I want a simple design for now, as I can add ...
0
votes
1
answer
287
views
Using 0-3 V sensor with 0-10 V PLC
I have a sensor that generates an analog 0-3 V output signal. I would like to connect this sensor to a PLC which has only 0-10 V analog inputs.
My questions are:
Is this recommended to do in general? ...
- 407
3
votes
2
answers
852
views
Algorithm for converting a 128-bit value to a string
I am trying to convert 128-bit data to a string in a PLC, but the PLC has max. 32-bit data. I store 128-bit data as a byte array and bit array. Now I need to convert this value to a string, but the ...
- 53