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  1. #1
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    TAC Vista question

    I have one small part, emergency room, of my hospital on a Vista system. The rest is Inet. I know Inet well but not Vista.

    My problem is they did a construction project and they replaced exhaust fans serving isolation rooms. All of the old Vista controls were removed. Old fans had VFD's, CT's for status, and static pressure switches. New fans have nothing. Vista has no way of knowing if fans are running or not.

    It appears the CAV boxes are commanded closed if Vista sees no fan status (that I have hard wired to show fan is running) or static pressure on the duct (that is harder to fool although I guess I could input about a 2 VDC signal to Xenta).

    If I can manage to pull up those CAV's in Menta what sort of block should I be looking to edit? I don't know how one would set that feature up so I don't know what to be looking to edit.

  2. #2
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    Integrate the VFD nodes using LON and bring in the status via the network.

    kontrol out

  3. #3
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    How hard would it be to just reconnect the fan CTs to the TAC controller binary inputs?

    If you can get into the Menta file, it will tell you which controller input the fan status is assigned to (I/O configuration from the top menus). Probably using something like a Xenta-421.

  4. #4
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    Fan CT isn't the problem. Already put a jumper wire across that digital input. Vista confirms fan status as "on" now. Seems I am going to have to fool the DP input. Would imagine it is a 0-10VDC input from a 0-10" pressure transducer.

    Seems easier to "unbind" DP senor from the five CAV boxes that serve isolation rooms. Just don't know how to do it Two different AHU's, two different isolation fans, fifty CAV boxes, and all of it is on-line in a busy emergency room. So I don't want to screw up any of the other stuff.

    Yes, it would be easier if they simply relocated original DP sensor to new fan/ductwork.......but there was no way that was happening.

  5. #5
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    I see where you are getting at. There is an analog input that tells the Menta file programming to enable the CAV. You are just wanting to permanently disable/put these points out of service.

    If I still had access to Menta software I could help ya out pretty easy. You could open the menta file and take a crap-load of screenshots and post them or email them maybe.

  6. #6
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    No offense, but bypassing/jumpering out air pressure controls in an isolation room is a bad idea. Call the contractor back out to fix or go back after the GC/Engineers to get this resolved...Isolation rooms and Liability I would think would expedite this for you....I can't imagine this passed any kind of inspection without interlocks/proof....
    "How it can be considered "Open" is beyond me. Calling it "voyeur-ed" would be more accurate." pka LeroyMac, SkyIsBlue, fka Freddy-B, Mongo, IndyBlue
    BIG Government = More Dependents
    "Any 'standard' would be great if it didn't get bastardised by corporate self interest." MatrixTransform
    My 5 yr old son "Dad, Siri is not very smart when there's no internet."


  7. #7
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    Crab master I was hoping you would jump in. Did a search on the forum and you seem most likely to be able to help.

    I only jumped out the digital input for the CT (fan status). I did so because I wanted to get the right CFM to the rooms (but it didn't work as planned). If rooms then went positive I would have ammo to complain. As it is now the rooms read negative (because they have no supply air) and that is all anyone seems to care about. I am beyond pissed but I do need my job. Used to be a great place to work but it was bought by a big evil corporation a couple of years ago and they don't do anything more than meet the minimum code requirements. If it wasn't for my age and 30 years of tenure I would leave.

    Because the isolation rooms are on a different floor and nothing was touched there these rooms won't be inspected. Makes me sick. I'm trying to get some help to make matters right for the safety of patients and staff. It has been made painfully clear that I will not get a VFD, CT, or differential pressure switch on the new fans. Nor may I call in my Vista expert because he no longer "works for a controls company" (which is BS).

    Not even going to bother y'all with what happened on supply air side and how many DDC cables were cut/shorted.

    Anyhow I can understand if you guys don't want to touch this with a ten foot pole. I freely admit I know nothing about Vista and don't even know If I can manage to pull up the right points in Menta. Originally all we had was a web browser interface and Vista was put in a couple of months ago as a good faith thing because the controls company was disbanding....so no training.
    Last edited by Russ57; 08-28-2015 at 07:48 PM.

  8. #8
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    I feel your pain. This discussion would be much more suited for the Pro's section.

    Start one up there and I'll continue.

    The other option is get word to the inspector that the new fan's also serve the isolation rooms and the controls have been gutted, so it needs inspected...
    "How it can be considered "Open" is beyond me. Calling it "voyeur-ed" would be more accurate." pka LeroyMac, SkyIsBlue, fka Freddy-B, Mongo, IndyBlue
    BIG Government = More Dependents
    "Any 'standard' would be great if it didn't get bastardised by corporate self interest." MatrixTransform
    My 5 yr old son "Dad, Siri is not very smart when there's no internet."


  9. #9
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    Thanks. Started new thread in pro's section.

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