LightingControl 1

[pithpal]

Hi Everybody,
You guys have answered my erlier question in a generator thread. Actually I work in a consulting engg. firm. My perception of working in a consulting firm was an illusion I think now a most of the work is done by the manufacturer. The engineer's work is to connect the strings only that is the reality. Not much of expertise is required but I joined thinking that I will get to learn.
here is the case: I am recent graduate and not a very practical person, the project is a lighting control, a retrofit. Now it is the manufacturer like Lutron, GE and others they give u all the relay panels depending upon what kind of scheduling we want. and also help u with location of occupancy sensors and dimmers. Now where is my role than, the role of an engineer. Anyways, Plz advise me any source on the web where I could learn about Basics of lighting control and automation.
Thanks

 

[arnsam]

hi pithpal,
i believe your completely not right by saying that your perception of working in a consulting firm was an illusion and you think now a most of the work is done by the manufacturer. IT IS NOT TRUE AT ALL. Being an engineer doesnot imply that you play with calculations for design works only!!!I worked with consulting firm for about 5yrs.
My advice to you is that try to understand the functions of consultants - as a consultant you will be represent the clients. - You will be required to administer the projects depending on the displine you are, by . As electrical consultant you will find yourself required to know a lot of things in relation with electrical eng. as the Clients will be expecting only positive answers from you.
Back to your question, I dont know the website for lighting design, but if you have IEEE wiring regulations and Australian Standard consultants handbooks will give you full approach for basic lighting design.

 

[itsmoked]

In your example I would say your role is:

A) Gather all the information required to properly carry out the job.

1) Lighting brightness required at each spot.
2) System break down. What controls run which area.
3) Allowed cost.
4) Where and how wiring will be routed.
5) Type of lighting at each spot.
6) Available mounting options.
7) Power, voltage, current source available.

Once this info is compiled.

B) Sketch out something that looks reasonable to you.
1) Take it to your suppliers. Get their input.

C) Using their input improve your sketch into a drawing of the plan.
1) Run this past someone experienced in this subject.
2) Make modifications to the plan based on their input.

D) Go back to the equipment suppliers with this plan.
1) Again get their input making sure no show stoppers are present.
2) Get quotes for all required material.
3) Get quotes for all labor.

E) Compile a complete package.
1) List of all contacts that you keep.
2) Finalized drawings.
3) Parts lists.
4) Schedule.

F) Celebrate.

Of course some of the above depends on info you didn't provide about your company's position in all this etc,etc. This would change your job in some respects.

 

[pithpal]

Thanks everybody. I beleive I had this opinion because I my self lack confidence in practical aspect of what I am doing. Please answer my this question. It is a basic concept but not getting in to my head.

When it comes to lighting control, first the option selected is, suppose occupany sensors and some schedules turn off and on and then sensors take over.
Now after this is selected , lot of companies have different options.
Option No.1 programmed relay panels and those connected to
sensors and power packs.

Now what bothers me is Contactors:
A contactor has a coil which when energized using 120 v or 277 v, it open or closed certain no, of contacts.
Now, that means if I am using contactors for lighting control , all the contacts depending upon some are normally closed or normally open, they will open or close. So I also read, A signal can be send to contactor to open or close certain contcts. How it is possible?
When a contactor coil is energized, all the contacts will come in to action. am I correct.


Q2 When lighting is controlled using contactors, what is the next element.
Hope your answers will help.
Thanks

 

[itsmoked]

"So I also read, A signal can be send to contactor to open or close certain contcts."

I read this as it is written... You can send a signal to a contactor that will open or close the contactor.. I don't see a problem here.

Q2: The next element is the lighting ballasts.

 

[pithpal]

Thanks for the reply itssmoked.
ok let me explain what I understood from this statement.
A contactor can receive only one signal and which will lead to energizing of coil and that might be through another relay which will complete the 120 v coil circuit.
I hope I am correct.
Now this action will get all the contactors contacts into action,"Againa I would emphasize ALL not certain" certain means some we want to; for example if I want to use energize 4 out of 8 contacts. Is this feasible. According to my information, all contacts will get in to motion.
I hope I made my self clear, what point i am not getting.
Thanks

 

[babylon]

A contactor is operated by means of a solenoid operation, whereby upon energisation of a coil (your signal), the solenoid will operate and the contacts will also operate.

You need to think of a contactor as a two state device, i.e. either energised or de-energised.

When you read that a contactor is N/C (normally closed), this represents its de-energised state. thus when the contactor coil is energised, the contact set will open.

contact sets can be N/C as described already, or N/O (normally open).
A contactor unit can have many contact sets, however they are usually in the range 1-6 poles.
It is not unusual to have multiple N/O and N/C contact sets within the contactor unit.
Another popular type is a change-over type contact set, which will alternate sources (similar to an ATS).

You can-not be selective of which contacts operate and which don't in your run of the mill contactor unit. The contacts are all linked up to the solenoid plunger mechanically within the contactor.

Recommend you use seperate contactors or alternatively a proper lighting control system using digital addressable ballasts and a control bus to each luminaire, thus you can individually program every fitting on your system.

Speak top a manufacturer about this, because as you quite rightly stated in the original post, the technology is such that us mere consultants are not able to design these systems for construction level detail any more.

 

[EEJaime]

Pithpal,

Engineers whom have a background in product design, machine design, circuit design and any number of electrical engineering specialties often see consulting engineering as less than true engineering. Given that we do not dream up new areas of research and development on a daily basis. But what we do do, is provide the worlds' window into all aspects of engineering. We as consultants are charged with creating environments with which all people will interact in one way or another. Lighting design is one area where substantial impacts can be made to the feel, look and operation of any facility. Lighting design and control will establish not only the feel of the spaces people occupy, but also the environment in which they will work, teach, study, practice medicine, heal, and jsut basically live for large segments of their lives.

ITSMOKED provided a very good outline of what the steps are in creating a functional and workable project. Keep in mind that depending on the type of project, there will also be steps in meeting and discussing with the client, architect, lighting designer, interior designer, acoustical consultant,etc..., to get at what the look and feel of each space,especially public spaces, should be. You have control over color, texture and functionality, mood, security and many other aspects of a facilities' operations.

It is important to know the options of lighting control available, as daylight harvesting, dimming, night lighting, emergency egress lighting, etc..., are considered. But any vendor can provide the nuts and bolts technical information. I recommend you look at lightingcontrols.com for added information, but as you have already stated, there are many sources.

My final point is that in todays market, with todays work ethic, (or lack thereof), many young designers have turned over design duties to vendors. I believe that is a critical error and results in inferior design because the goals are not what the client hires us for-the vendors goal is to put as much of his product onto the construction documents and ultiately into the building as possible. We must remember that these are sales people. The product they are touting this week, they were disparaging last week, and will again next week. It is critical to build trusting relationships with professionals whom can provide you with the information you need and allow you to design a facility for your client. Our mandate is to provide the client with a well designed facility which meets his needs for function, while working with the building designers' vision for the aesthetic aspects of the facility. Where we as engineers do our best work is behind the scenes. Specifying and holding the specification for products which are of the maximum quality the budget will allow, which will perform for the maximum life possible, and which will provide a space, building or campus which twenty years from now, we can drive by and proudly say- "I did that!"

 

[itsmoked]

Nice and clear EEJaime.

 

[advidana]

Electrical Engineering and Lighting Controls may seem easy until something goes wrong then you just lose your job. The vendors and contractors will point the at the design when thing go wrong, so it is a good idea to know what you are doing.

It look like the place you are working at does not provide any in house training. I would suggest that you take a lighting course and read a few books on lighting controls from your technical book store or from an line books stores that have books available on this subject as soon as possible.

The Electrical engineering designer is the expert not the the sales guy or the tech. Your client expects you to be responsible as well as the law in some places. Checking with this site was a good first move, but, you need a lot more. Engineering is just like any other job it looks easy until you start doing it on a day to day basis.

good luck

 

[pithpal]

Thanks Advidana,
I agree what you said. When one does not have a strong ground to stand, the things may fall.
So I need to have some background in lighting control. I have ordered an Application binder from a lighting control company. I would appreciate if you could advise me some online source or some books. I am in to power but this lighting controls looks like kind of controls thing so this relay things are hard to grab, but I will surely give them a try.
Thanks

 

[advidana]

it's old and new technology mixed up. if you can find something on relays logic it would help a lot. Everything as going to programable controllers so basic relays are not stress in college or schools at all. Lighting contactors and motor contactors are just relays with heavy duty contacts. learn about relays first then apply this knownledge to contactors. It would help to wire one up and see how it works. try an easy simple one. Square D has a simple book on relays that is avalible from them at no cost. I will see if I can find a copy so I can get you the name or title of the bulletin.
bye are now

 

[pithpal]

Thanks advidana, I appreciate your reply and please advise me, if you found the book.

 

[advidana]

I found it. Square D Company "Motor Control Fundamentals" SM 368-R3.

 

[mnnc]

Hi advidana,

there are no square d company here. Those the are, are distributers of square d. Where can i get copy of motor controls fundamentals?

Thanks.

 

[pithpal]

Thanks Advidana,
Actually the catalouge number has changed.
iF some body needs
google with
"0140BR9102"

just put this number in google and you will come across a document detail page, the first search result.

Just get in to it and you will find it.
Thanks