Vacuum monitoring
Vacuum monitoring
(OP)
We have a central vacuum system that runs at 27Hg, I need to build or buy a sensoring device to alarm low or high vacuum. I am lookoing for any ideas or suggestions
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RE: Vacuum monitoring
Use a pressure/vacuum switch. Pipe the threaded connection to the process.
Wire the switch output to drive whatever you're thinking is going to be the alarm.
United Electric model H100-218 uses wetted brass/bronze sensor. No scale for adjusting the trip point.
H400-S126B uses 316SS wetted sensor, has an scale for adjusting the trip point.
Or you can use a gauge pressure/vacuum transmitter feeding an analog signal to an indicator with alarm relays or an alarm module.
Avoid the distributor who mistakenly tells you that you need an 'absolute' pressure anything. When you use terms like 27"Hg, then your vacuum is gauge pressure vacuum, referenced to atmosphere, not absolute pressure, referenced to absolute zero.
RE: Vacuum monitoring
Gunnar Englund
www.gke.org
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Half full - Half empty? I don't mind. It's what in it that counts.
RE: Vacuum monitoring
Either a gauge type set for a negative pressure or if your process is effected by the ambient pressure changes an Absolute range transmitter.
Roy
RE: Vacuum monitoring
Contact type self contained for shutdown device around the PLC for too much vacuum? damage to equipment or collaspe the vessel if too much vacuum similar to an estop input.
Or like above using a 4-20mA type vacuum to see the vacuum setting?
RE: Vacuum monitoring
http://www.ifm.com/ifmus/web/pmain040_010_010_030....
Analog and switch points on the same device - and very reliable
RE: Vacuum monitoring
Also range of the measurement is ir 27 mm Hg or 27" Hg very diferent measurement accuracy needed.
Mark Hutton