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Q: Lighting relays and lighting control via LAN... ( Answered,   0 Comments )
Subject: Lighting relays and lighting control via LAN...
Category: Computers > Hardware
Asked by: curiogeorges-ga
List Price: $25.00
Posted: 10 Oct 2002 20:30 PDT
Expires: 09 Nov 2002 19:30 PST
Question ID: 75116
First of all, I want to know how lighting relays work in layman terms.
 Second, I would like you to find an easy to use lighting
relay/lighting control product for a restaurant.  Ideally, I want a
relay product that would allow me to set lighting schedules for
various lights and appliances, AND I want to be able to control the
lighting schedules, dimming, etc. via computer (via Ethernet network,
etc.).  Please help!

Clarification of Question by curiogeorges-ga on 11 Oct 2002 11:24 PDT
By the way, I do NOT want X10 products.

Request for Question Clarification by haversian-ga on 11 Oct 2002 23:16 PDT
Could you clarify what you mean by "lighting relays"?  I can tell you
how relays in general work if you'd like.

Are you looking for something specific to lighting, or would any
computer-controlled relay (for standard outlets) be acceptable?

Dimming is not a matter of relays, which are on/off devices - you will
be needing a solution which does dimming as well?

Do you need something to control a few devices, or does it need to
scale to dozens of outlets?  Also, what price range are we talking
about here?  I presume that if you're running a restaurant with this,
you'd prefer to pay more to get something easy and simple to operate
rather than spending time tinkering with it; is that correct?
Subject: Re: Lighting relays and lighting control via LAN...
Answered By: vinods-ga on 12 Oct 2002 01:29 PDT

Lighting control or relays (used generically here) consists of a
network of control devices that: 1. turn lights on and off & 2. dim or
brighten lights, i.e., control intensity.

Initially any kind of remote switching operation used
electro-mechanical relays, devices that could control the switching of
an electrical load by means of a control signal. Later, semiconductors
- transistors and more advanced devices were used to do this. To get a
basic idea of relays, please see:

---------- RELAYS ---------------

[ ] 
Copyright 2001 ELH Communications Ltd. all rights reserved.

-- Excerpt -- 
A relay is a remotely controlled operated switch; it consists of one
or more contact pairs that serve to open, close or transfer external
circuits. The relay is just a switch, activated by electricity. A
relay is a simple electromechanical switch made up of an electromagnet
and a set of contacts.

Relay basics
[ ] 
by: Andrew Krause

Relays are one of the oldest, simplest, and yet, easiest and most
useful devices. Before the advent of the mass produced transistor,
computers were made from either relays or vacuum tubes, or both.

A relay, quite simply, is a small machine consisting of an
electromagnet (coil), a switch, and a spring. The spring holds the
switch in one position, until a current is passed through the coil.
The coil generates a magnetic field which moves the switch. It's that
simple. You can use a very small amount of current to activate a
relay, and the switch can often handle a lot of current.

The relay discussed above is an electro-mechanical device. It has an
electrical section that drives a mechanical section that in turn
drives yet another electrical section. There are semiconductor-based
Solid State Relays too.

[ ]
Copyright 2001 ELH Communications Ltd. all rights reserved.

----------------------------------- end of RELAYS ----------

You can also refer to the '' pages to get an idea of what
dimmers are and how do they work.

Most lighting control devices have communication ports through which
you can setup a computer as a control device. Since the control
devices are 'solid-state', they can be sent control signals through a
digital system. Basically the use of the computer in this is to
facilitate two-way communication between the various devices in the
lighting control network - send control signals as commands and
receive feedback from various devices about their current state, etc.
Therefore the computer acts as a 'communication center' through which
various controls, timing schedules etc., can be 'programmed in' for
remote and automated operation of a complex network of devices.

This URL contains links to several pages in information on lighting
devices, controls etc.
Copyright 2001 ELH Communications Ltd. all rights reserved.
In many situations, luminiares are not used constantly at full power.
They are generally required to fade in and out, and to be used at
different brightnesses, or intensities, at different times. A device
is required to regulate the amount of electrical voltage sent to each
luminaire, thereby allowing the intensity of the light to be varied:
this is a dimmer.

A light dimmmer allows controlling of a light bulb brightness. The
basic idea of dimmer opertion is that it limit the electrical power
that gets to the light bulb. Dimmers today come in many styles to
control different types of loads. In some old mains powere lighting
systems variable transformer is used as light dimmers, but nowadays
they are largely replaced by electronic light dimmers with operate
using phase control principle (first this kind of SCR based system was
publicly demonstrated in 1962 in London).
Solid state relay (SSR) and semiconductor relay are both names of
relay like device which works like a normal relay. A basic definition
of a totally solid state relay is a device that operates a load
circuit without the use of physical contacts.

[ ]
-- excerpt -- 
To understand how luminiares are controlled from the lighting desk, it
is necessary to look first at the dimming system. Working back from
the luminaire to the operator, the complete control system comprises:

Dimming system; 
Control desk; 
Control protocol. 

Control Data Communication
[ ]

Control Communication Protocols

Lighting Control & Design - Application guide - restaurant

Lighting Controls Dimming & Relay Systems - JTH Lighting Alliance
[ ]

FUTRONIX - leading the world in digital dimming
[ ]

Digital Lighting Systems 
[ ] 

Improve restaurant Lighting by Installing Dimmers
[ ]

Lighting Controls Association
[ ]

Lighting Controls Association - Education Centre
"We've scoured the web to bring you the best of the best in lighting
controls and controllable ballast general information, research,
technical issues and application ideas."
[ ] 

Lux Lighting Design
[ ]
lux lighting design - insights - The Psychology of Lighting
[ ]

google search keywords:
lighting control basics
lighting control fundamentals
lighting control design
lighting control design basics
lighting control design fundamentals
lighting control technology 
lighting control relay
lighting control relay basics
lighting control overview
lighting control computerised
relay basics
restaurant lighting control

Please do get back to me if you need anymore information or any

warm regards

Request for Answer Clarification by curiogeorges-ga on 12 Oct 2002 17:08 PDT
What I need is a solution for a small restaurant.  Essentially, I want
certain lights to go on before opening, certain lights to turn on when
it gets dark and certain lights to dim.  Turning on/off appliances is
also a need.  So, the solution lies either in the local switch or a
central control panel.  I want to be able to change the settings via
computer (over ethernet).

Clarification of Answer by vinods-ga on 12 Oct 2002 22:56 PDT
Hi Curiogeorges, 

The system will consist of timer-based switches, timer and sensor -
based dimmers and an RS 4XX control to run the whole network by a
computer. Once you have a computer, networking and remote operation is
possible, but is also separate from the actual lighting control

The solution you require is a 'turn-key' project. You require a
lighting control design specifically to suit your needs. I would
recommend that you look for a design company in your city. The should
be able to provide you with a tailor-made system by inspecting your
restaurant, deciding the various components and finally design and
build the network.

Al with all systems, some degree of maintenance and repairs may be
required from time to time and it will be an advantage to have the
company that designed the system to also take care of this.

I don't know where you are located, but from the list of URLs I had
sent you,
Lighting Controls Association 
[ ]
should be able to help you find a solution-provider in your vicinity.

Warm regards
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