Energy/ Building Management companies

[scoker]

Hello,
I am investigating companies to supply systems for energy and building management. These systems would collect data and control the HVAC equipment at up to 40 current buildings and any future new construction. Honeywell, Siemens, Johnson Controls have been some names that have come up so far. Any experiences or input would be appreciated.
Thank you in advance.

 

[spector]

We have the J/C Metasys system.....It is a constant nightmare, just a few years old and already obsolete. Several Metasys failures have cost us tons of downtime and expensive repairs.

Last year our 3 chillers lost the ability to 'talk' to Metasys. As our Metasys translator cards are now "obsolete", we had to pay J/C $19K to custom make 3 little PC cards to allow our chillers to communicate with the rest of their system. Getting them to respond to other than the most severe failure is almost impossible. It's like they only want to show up when they can demand the really BIG BUCKS. Getting them to provide routine service has been impossible.

Twice in the last year, Metasys ordered 12" CW flow valves fully shut causing extreme overheating and overpressure in our chillers. Each time we were within just a fraction of a Lb of bursting rupture discs where we would have lost the complete charge of refrigerant. J/C cannot offer a reason for the spurious control action, much less a fix. So we have disconnected all operating air to those valves and in doing so, given up any efficiency J/C insisted they would provide.

This year we installed Honeywell digital controls on our boilers. I must say that they are completely trouble free and reliable.

Which ever make you select, make sure to first check out their record.

 

[Whoops]

Which country? I've recommend Trend (UK).

 

[scoker]

I am in the Midwest in the US

 

[jclair]

I have been designing and commissioning control systems for almost 10 years, and without a doubt the biggest factor is the people who perform the installation, startup and service. As noted previously, many of the larger companies, because product development takes a "long time" in technology terms, have trouble keeping products up to date. I would recommend soliciting similar facilities in your area to determine the systems integrators in your area who have the most knowledgeable staff and provide the best service.

Depending on your general location in the midwest, I may be able to help you with that.

 

[referdude]

Our facility has a Trane Tracer Summit system for the HVAC and light mask scheduling. It seems to work quitye well. Our freezer Refrigeration system is controlled by an Allen Bradley unit. Some special energy saving devices that are integrated are Variable Frequency Drives on screw compressors, condensor fans and evaporator fans. Also, we have bi-level HID lighting (both in metal halide and high pressure sodium)

 

[nrgsaver]

I would agree with jclair regarding the track record of the companies designing and installing the systems. I would also add that having worked for two large control companies (Honeywell and Siemens) and now a systems company (Trane) I have learned more about controlling equipment in the last 12 months than in the previous 12 years. I guess what I am saying is that there is a control mentality and there is an equipment mentality that needs to be melded for satisfactory performance and I never saw that working at the control companies. The pure control companies open and closed valves with out really thinking about the ultimate effect on the equipment. I also saw very little in the way of commissioning experience with those companies. With a system's approach, one needs to balance the control needs with the equipment function. This is a "hard to describe but I know it when I see it" kind of thing.

To summarize, all most all of the control systems will perform the same or nearly similar functionality. I few will be quicker, a few pennies cheaper or have an added whistle or two. I would look for a company that has experience in integrating their controls with the equipment you are trying to control, has solid commissioning protocols as in inate process and finally an open protocol system such as BACNET and/or LonWorks in case things don't work out.

 

[port]

look at

http://www.pervidi.com

 

[JimboSliga]

One factor to consider in selecting a Building Automation System (BAS) is "interoperability". Many systems are proprietary; once established, only one vendor's product can be used to expand the existing systems. Without competitive bidding, expansions become very expensive. Interoperable systems allow an owner to use various vendor products when expanding their BAS systems. These type systems use non-proprietary platform protocols. Some of the more familiar are LonWorks and BACNET. Even with these, one must read the "fine print" to look for "proprietary hooks" that make some components vendor-specific.

 

[sysint]

Maybe take a look at the new USGA specification for building automation. They selected LNS Lonworks platform.

 

[MintJulep]

Some excellent points here already, but one crucial thing is missing.

You absolutely must develop a comprehensive and unambiguous System Requirements Specification BEFORE your even send out RFQ's.

What do you need the data for? Who will use it, and what format is needed? When do you need it? Any company can give you data, but reams of paper with endless lines of Hex numbers representing events that happened three months ago really isn't useful is it?

What system parameters does the control system need to maintain? What equipment characteristics need to be considered to protect the equipment? What is your utility rate structure? Running a big chiller with on/off control can achieved the same system effect as a modulated VFD, but might reak havoc with demand charges, and could reduce motor life from overheating. On the flip-side, if you try to run it too slow through a VFD you might not develop enough oil pressure, and trash the bearings.

 

[HVAC68]

I agree with MintJulep. Some more points to add, though. Consultants (with due respects to them) have a tendency to put in more and more points through the BMS just because it's possible to do so. Just check out what is your requirement of BMS and don't add unnecessary points and functions if you don't need them. Put your thoughts down from a functional point of view and decide the sophistication you need. The more sophisticated you make your BMS, the more the trouble it creates.

One more crucial factor - get the right guy to do the job for you. Very hard to get a controls guy who understands HVAC thoroughly from both a theoretical and practical point of view. Most of the the controls specialists I have seen (except a couple of rare breed of guys who are HVAC engineers who have become control specialists) don't understand HVAC the way a HVAC engineer understands it.

Good luck.

HVAC68