April 2010

AutomatedBuildings.com

Innovations in Comfort, Efficiency, and Safety Solutions.
Belimo

(Click Message to Learn More)


Controls Contracting Operations - Installation
Getting from point A to point B, successfully!

Part 2 of 3

Steven R. Calabrese
Steven R. Calabrese
Control Engineering Corp.

Contributing Editor

Last month we discussed the “preconstruction” phase of a project, (Part 1 of 3) and covered some of the things that need to happen during this phase, not the least of which was getting the “hardware engineering” completed and out the door for review and approval by the engineer-of-record. Assuming that all went well and the temperature controls submittal came back approved, you can now move into the next phase: installation. First up is ordering the components for the project.

Articles
Interviews
Releases
New Products
Reviews
Editorial

Securing Buildings News

Coming Events
Sponsors
Site Search
Blogs
Archives
Past Issues
Home

ABB

Parts Procurement

During the engineering process, a spreadsheet was (should have been) generated that contains a list of all of the unique components required for the job, and their quantities. If your submittal generation process is somewhat automated, then this spreadsheet, or Bill of Materials, might enable you to quickly and efficiently order all of the parts. At any rate, you’ll need to purchase everything on the list, in the correct quantities, and have them shipped in time for installation. A few things to be aware of when placing orders…

For those “big ticket” items, check to see if they were quoted during the pre-booking process. The sales engineer may have procured quotations on such items as dampers, airflow measuring stations, control valves, and the like. For items of which you need a lot of, inquire about “bulk” pricing. Be aware of lead times. Most of the things purchased will have short lead times (less than two weeks). However there’s sure to be items that will have longer lead times, and you need to know this in order to be able to receive them prior to when they’re needed on the job. Finally, consider your delivery options. Will the parts ship to your office, such that you can take inventory of them and deliver them to the jobsite? Or will some of the items ship directly to the site? Items such as damper lots and larger heavy control valves are better off shipping to the jobsite. This needs to be coordinated with the trades that are to accept these items for installation, and there needs to be a place onsite where these items can be secured until they’re ready to be installed.

Handling Uncertainties

Ever get the feeling that you don’t quite have everything covered? Care to minimize that feeling? Thought so! Well, the topic of this section is all about that. Every project, no matter how small or how large, no matter how simple or how complex, will no doubt have uncertainties. That’s a given. How you handle them is up to you, but included here are some simple suggestions borne out of, you might say, “learning the hard way”.

First off, and this perhaps comes into play more in the engineering phase of the project, overestimate your point count. Specifically, when selecting controllers, be mindful of the prospect of more points being added down the road. Oftentimes a consulting engineer will specify a certain percentage of “spares”, and for good reason. Murphy’s law dictates that if you select a controller and max out its capacity of, say, binary outputs, then sometime during the installation phase a need for another binary output will present itself. Happens every time! Understand that it’s not always economical to blindly oversize your controllers to accommodate spares, however you need to at least put some thought into this, or into how you will handle it when you do end up needing “just one more output”.

contemporary Pull extra cable. Not for every cable run. But when you know that a cable run is going to be long, difficult, and have a potential for the need for more conductors down the road, what’s the harm in pulling an extra pair? Trick is to be aware of this and be able to recognize when to direct your field labor to do this.

Think through worst-case scenarios, and their implications. What is the worst thing that can happen as a result of this particular uncertainty? Can you live with the consequences? Is there a solution to it, albeit costly or complex? Is it worth taking a chance on it? We can’t build safeties into every aspect of what we do. There will always be some risk, the flipside of that is how we profit. Yet we need to be aware of the risks, and we need to spend a little time playing out the worst-case consequences, lest we be blindsided somewhere down the road.

Communication is the key. Constant communication with all players is key to a successful project. If communication is lost and things are “left to chance”, then the prospects of a successful outcome are greatly reduced. Establish a line of communication initially, early on in the project before opinions get a chance to formulate, with everyone involved on your end of the project. This includes (but is not limited to) the mechanical contractor, general contractor, electrical contractor, and the consulting engineer. Equally important, maintain that clear line of communication out to all parties. Even just “checking in” when you don’t have a specific issue to discuss, is appreciated and goes a long way toward maintaining a good rapport with your customer, and your customer’s customer as well.

Coordination Between Trades

Trade coordination refers to the notion that the controls contractor has certain tasks that are more or less “shared” between them and the other trades, most notably the sheet metal and piping trades.

On the airside, the controls contractor will provide certain items that will need to be installed by the tradesmen putting up the ductwork. These include automatic dampers and airflow monitoring probes, the locations of which need to be coordinated between the two trades. In the case of the dampers, the damper actuators will be installed “after-the-fact” by the controls contractor, as it is considered “electrical work”.

On the waterside, the controls contractor will typically be providing items such as automatic control valves (actuators pre-mounted), immersion sensors and wells, pressure transmitters, and flow devices (meters and flow switches). It is the responsibility of the piping tradesmen, again through proper coordination with the controls contractor, to install the control valves, the wells for the immersion sensors, the pressure taps for any transmitters provided, and the required piping connections for any flow devices. The controls contractor must “mark up” a piping layout showing all devices and their locations, and must meet with the pipefitter on site to go over these locations.

Tip of the Month:
So important is the documentation trail throughout a project that it is good practice to keep a journal, dedicated specifically to the project. A small wirebound notebook will suffice for smaller projects, whereas you may want to keep a larger, more structured journal for large or complicated projects. Either way, you’re sure to benefit from keeping good notes in a traceable format, for sooner or later, something will come up that will make all the time you invested in your journal totally worthwhile!

Documentation Upkeep

Throughout the course of the project, there will be modifications to the plans, to the intended sequences of operation, and to the control systems design. These changes are driven by the process itself, as nothing has ever been designed so perfectly that it doesn’t need some change in design or in how it’s installed, even be it ever so small. Case-in-point is when the installation crew points out something to the project manager, in how to do something quicker and more efficiently, without compromising the design intents. Or when the control systems design engineer recognizes an error on the drawings, and needs to make amends.

For these reasons it’s imperative that the project manager keep an ongoing record of changes that come up throughout the course of the project. From the day that submittal package comes back from the engineer-of-record, the project manager should take ownership of his own copy to keep for reference and to track changes. For any change made, it’s good practice to sketch the change on the appropriate drawing, and, this is important, date the change! You will find yourself going back to the change weeks, even months later, and you’ll be glad you dated it, to put you back in that timeframe along with all the other dated documentation that you may keep (letters, emails, etc.). Makes it a whole lot easier to remember, or rediscover, why you made that change in the first place!

 

footer

switch
[Click Banner To Learn More]

[Home Page]  [The Automator]  [About]  [Subscribe ]  [Contact Us]

Events

Want Ads

Our Sponsors

Resources