• Welcome to PlumbersForums.net - The international free plumbing advice forum. Professional plumbers sharing advice with fellow plumbers and DIY alike. Register for free today! - Checkout the Plumbing Advice forum and then our Plumbing Videos area which still needs populating.

control

Control theory deals with the control of dynamical systems in engineered processes and machines. The objective is to develop a model or algorithm governing the application of system inputs to drive the system to a desired state, while minimizing any delay, overshoot, or steady-state error and ensuring a level of control stability; often with the aim to achieve a degree of optimality.
To do this, a controller with the requisite corrective behavior is required. This controller monitors the controlled process variable (PV), and compares it with the reference or set point (SP). The difference between actual and desired value of the process variable, called the error signal, or SP-PV error, is applied as feedback to generate a control action to bring the controlled process variable to the same value as the set point. Other aspects which are also studied are controllability and observability. This is the basis for the advanced type of automation that revolutionized manufacturing, aircraft, communications and other industries. This is feedback control, which involves taking measurements using a sensor and making calculated adjustments to keep the measured variable within a set range by means of a "final control element", such as a control valve.Extensive use is usually made of a diagrammatic style known as the block diagram. In it the transfer function, also known as the system function or network function, is a mathematical model of the relation between the input and output based on the differential equations describing the system.
Control theory dates from the 19th century, when the theoretical basis for the operation of governors was first described by James Clerk Maxwell. Control theory was further advanced by Edward Routh in 1874, Charles Sturm and in 1895, Adolf Hurwitz, who all contributed to the establishment of control stability criteria; and from 1922 onwards, the development of PID control theory by Nicolas Minorsky.
Although a major application of mathematical control theory is in control systems engineering, which deals with the design of process control systems for industry, other applications range far beyond this. As the general theory of feedback systems, control theory is useful wherever feedback occurs - thus control theory also has applications in life sciences, computer engineering, sociology and operation research.

View More On Wikipedia.org
  1. P

    House with two boilers - Smart heating control possible?

    Hi all - my prospective house I am buyig has been split effectively into two parts with Boiler 1 provided Heat/Water to the first few floors and Boiler 2 providing Heat/Water to the top floors. So two separate Primary and Secondary Circuits. Is there a Smart system that would enable unified...
  2. K

    Vaillant EcoFit Pure 835 Temperature Panel Control

    Hello all, Just moved into a house with a Vaillant EcoFit Pure 835 boiler that is 3-4 years old but the previous owner did not bother to register with Vaillant, so Vaillant says its not under warranty. I've noticed that despite setting the CH to 60 degrees on the boiler's control panel, the...
  3. Bookalon

    hot water cylinder control valve

    Hi, I have an oil burner which is controlled via Tado to heat my home. My hot water cylinder is heated with water from the burner and also has a dumb immersion. I don’t use the immersion at all And would like to replace it. The burner heats the water in my hot water cylinder with a TRV valve...
  4. J

    Radiator Noise/Issue

    Hello everyone! I purchased this steam vent valve: Hoffman Steam Air Vent 40, 1/8" Angle Steam Radiator Air Valve 401440. Installed it and the hissing is much reduced but now, the hissing happens every 10-20 seconds for about two seconds. Its annoying enough to wake me up at night (I wish I...
  5. G

    boiler locks out , complete service and parts change

    problem with my oil boiler everything has been change all cleaned out set up but still locks out , if I remove photcell and shine a light on it it runs fine replace photocell and it stops again , new cell and control box, heating engineer is beat now as well
  6. Martdj

    ideal Isar He30 boiler works but the contol panel appears to be dead

    I have an ideal Isar He30 ( yes I know they are crap!) the boiler works but the contol panel asppears to be dead, the DHW and CH temperature controls have no effect and the boiler runs at max temp on both DHW and CH. I have repalced the display/contol panel and it still appearsto be dead. Would...
  7. Nickyd

    Boiler remote control

    Hi. I have a 15 year old Cosmogas Boiler in our house in Italy. It does 3 circuits: Hot water, Underfloor heating and normal radiator heating. I want to install a wifi controller to operate it remotely but not sure if this is possible. I currently have a Honeywell CR04 controller next to the...
  8. A

    Where To Buy SIME Brava Remote Control Home

    Hi, I looking for a 'SIME Brava Remote Control Home' from an online store. If you know of such a place, please share the website with me. Thanks in advance, Ayman
  9. E

    No programmer to control radiators

    I recently moved into a new property which has a gas boiler and: (1) A hot water tank - this is controlled by a Hive timer programmer (all good); (2) Wet underfloor system on ground floor - this is controlled by Heatmiser thermostats (all good); and (3) Radiators on first floor and towel...
  10. C

    Old(ish) Grundfos proportional pressure control circulator

    I'm trying to set up a Honeywell DU145 ABV with an ALPHA 15-60 130 (Model number 59526443) and work out the speed setting. The pump has one variable dial (no C1/2/3 ect). Grundfos support have no info on the pump as its from circa 2001, so unable to help. Its running 5 rads in a small 2 bed...
  11. R

    control underfloor heating pump wirelessly?

    hello newbie diy-er here looking for some guidance please :) gas boiler (downstairs) was connected to underfloor heating pump and valve (attic, along with hot water storage tank), coming on with the hot water the wiring between the two has failed - cable was exposed to water leak - so now I...
  12. H

    Replacing a motorized gas control valve with manual

    Replacing a remote gas control valve with its manual equivalent. My daughter has a gas coal effect fire. First, I know they're crap, she'll just use it for the occasional time that friends come round. OK, so it has a remote (broken), a remote receiver (broken) and a motorised gas control...
  13. M

    Heating control prob,em

    Setting 2 won’t override and still comes on when in the OFF position
  14. B

    Bristan mixer bar shower leaking from the temperature control

    I installed a Bristan mixer bar shower about two and-a-half-years ago. I have recently noticed that immediately after the shower has been used, it drips from where temperature control knob turns. I attach a photo. The temperature control is on the right-hand side. The drips last for about...
  15. T

    Replacing the control system... it's a real mess!

    Hi all, I've previously been helped on here by kind people so I'm tackling my next challenge. We have a GSHP (installed by previous owners) that supplies a buffer tank. That all runs OK. The heating pump and manifold actuators are 'controlled' by three OJ Electronics WLM3s (one master and two...
  16. D

    concord wrs 55. control unit

    Morning Everyone. I have an Ideal concord WRS 55. i know ! 40 something yrs old. The Honeywell stat and control board have mostly failed. no thermostat temp control or daily on/off timer only works on the 1 hr timer. no model No on either the stat unit or control board. can anyone tell me what...
  17. A

    Vaillant Ecotec Plus Combi & UFH Control - V Smart Possible?

    Hi All Looking at having controls replaced / upgraded for a Vaillant Ecotect plus combi boiler. Currently have x2 zone valves on the heating (x1 for rads via a Honeywell wireless stat, and x1 for UFH circuits via Heatmiser stats - both wired to a Heatmiser wiring centre) I'm interested in...
  18. T

    Is my circulation pump failing or my boiler control?

    I have a Viessmann Vitogas 100, installed about 17 years ago by a previous homeowner. It also is the boiler for hot water, so it runs all summer in hot water only mode. I’ve turned the heating component back on, but it’s not working properly. It would appear the circulation pump stops working...
  19. N

    Replace control unit with Nest

    Hello, I have a LOGIC a combo Esp1 35 boiler and CM707 control unit. I want to install Nest - however from looking online the two inputs are 240v from the boiler (cables are thick). Were it not for the voltage it looks a simple job. How can I do this myself ? Thanks
  20. philw67

    Atag One control when on holiday

    Can someone help please? Customer support from ATAG is non existent as the house we have bought had this installed a few years ago and despite sending them a picture of the install document they are not helping which is impossibly frustrating. Two questions. 1) this is a pic of the info after a...
Creating content since 2001. Untold Media is a Registered Trademark.
Top