Fan/Filter Pressure Overview
(Data covered in this post is highlighted inside the green rectangle)
Fan Pressure: each specific fan can provide certain air volume at certain static pressure based on its fan curve. The fan must create enough pressure to overcome all system pressure losses (hood losses, duct losses, filter losses, return air losses). Insufficient pressure will reduce system air volume - i.e. system is not working correctly.
Filter Pressure indicates whether the bag cleaning function is working properly or if the bags need to be replaced. Typically 0-2" w.c. is proper filter pressure of new bags, 2-5" w.c. is normal, above 5” w.c. is considered excessive and the bags should be replaced. A good dust collector should have a cleaning system (typically reverse pulse cleaning) to keep filter bags clean for a very long time. Bag cleaning depends on air velocity through the filter media (usually specified as air to cloth ratio, units are FPM). The lower the air velocity through the filter media, the easier it is for bag cleaning - i.e. bags will last longer. Because the Ecogate system is reducing system air volume by closing the gates at non active workstations, the filter air velocity is reduced, cleaning works better and filters will last longer.
How to read the data
Since the fan pressure and air volume are closely related, both of these values need to be evaluated together. Each fan at certain static pressure will provide corresponding airflow based on resistance of the connected duct system (as defined by fan and system curve). Therefore you should monitor both the Fan Pressure and Avg. Main Duct Air Volume to understand whether your fan is providing the performance that is true to its specification. Monitor filter pressure monthly to understand how well the cleaning mechanism of the dust collector performs. Monitor the filter pressure to predict how long before you need to change the bag and how long bags last.
Filter pressure should stay low with Ecogate. If the filter pressure value slowly increases everyday, that could be a strong indication that the cleaning mechanism of the dust collection is not working properly (reverse pulse jet, shaker, compressed air, etc).
This article is part of a sequence: Ecogate's Daily Analytics Report. Click Here to start from the top of the sequence.
Authors: Thanh Vu, Ales Litomisky