View Full Version : instrumentation HVAC
02-14-2005, 05:40 PM
I am trying to select some equipments for measurements in one HVAC system. But I am not sure if my considerations are right.
1- gauge pressure: I need one sensor for gauge pressure in pharmaceutical environment that it is chemically compatible with steam formaldehyde(3%). The measurement is for clean rooms. Which one can you recommended? Thanks
02-15-2005, 07:29 PM
if you are trying to measure whether the room is positive or negative, the usual device used would be a magnehelic. if looking for some other measurement, be more specific.
02-16-2005, 09:35 PM
"Flange" thanks for your reply. I need to measure pressure in the room and you´re right, is positive (0 to +60Pa)or negative (0 to -120 Pa)low pressure. The room will be bio-controlled areas without external contact, then the equipment should be gauge or absolute. The magnehelic is only differential pressure? Additionally, how is the montage? In wall? There are a lot of rooms in one cascade arrange. Thanks in advance for your support and regards.
02-17-2005, 06:12 PM
not sure what you mean by montage, but mags can be mounted remotely in a panel, either through the door or inside. there are various ranges which should suit your needs.
02-23-2005, 08:50 PM
A properly calibrated magnahelic is fine when the dfifferential is reading from a true atmospheric pressure vs. Clean Room. Plan on having a rotational one because the chamber guys probably cant calibrate it with any certificate or traceable standard.
Also check on Dwyer in the form of a specialized, spirit filled incline manaometer.
02-23-2005, 09:02 PM
My experience has been that with cascading labs the pressure is not necessarily measured against an unconditioned space or outdoor, but rather in reference to the next lab , with the most critical lab being the most negative and so on, I have setup labs dealing with HIV and tuberculosis and this was the set-up they had. The labs were in a circular format with the main lab being the center and negative to all of the other labs and the other labs being negative to the rest of the building and the building being positive to outdoors.
Are you looking for a meter that you can just read or a meter that can output some type of sigmal for an alarm or control,
One manufacturer you can try is Veris Industries,
[Edited by fat eddy on 02-23-2005 at 09:10 PM]
Powered by vBulletin® Version 4.2.0 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.