Apparatus for testing a filter

Abstract

A preferred form of the invention is directed to a system and method used to test filters. The system preferably includes a base unit and a probe operably associated with the base unit. The probe is configured to be deployed adjacent the filter being tested while the filter is located in an operating position. The probe is further configured to allow an operator to vary the mode of operation of the base unit from the probe. The system is configured to automatically exhaust any residual test sample from the base unit and the probe when the system changes between testing a sample upstream and downstream of the filter. The system further includes noise suppression on at least one of the upstream test sample and downstream test sample. The system further is configured to detect when the probe is connected to the base unit.

We claim: 
     
         1 . An apparatus for testing a filter in situ, said apparatus comprising:
 (a) a base unit being configured to operate in at least a first mode and a second mode, in the first mode said base unit being configured to perform a first test and in the second mode said base unit being configured to operate in a manner different than said first mode; and,   (b) a probe operably connected to said base unit, said probe being configured to be deployed adjacent the filter being tested while the filter being tested is located in a normal operating position, said probe further being configured to allow a user to change a mode of said base unit between said first mode and said second mode from said probe.   
     
     
         2 . An apparatus as set forth in  claim 1 , wherein:
 (a) in said first mode said base unit is configured to receive and analyze an upstream test sample taken upstream of a filter being tested, in said second mode said base unit is configured to receive and analyze a downstream test sample taken downstream of a filter being tested; and,   (b) said base unit includes a photometer for analyzing the upstream test sample and the downstream test sample.   
     
     
         3 . An apparatus as set forth in  claim 1 , wherein:
 (a) said probe is a handheld probe.   
     
     
         4 . An apparatus as set forth in  claim 3 , wherein:
 (a) said handheld probe includes a plurality of user input areas that allow the user to place the base unit in each of the following modes: (i) pause mode in which filter testing is temporarily suspended; (ii) a first operating mode in which said base unit is configured to receive and analyze an upstream test sample taken upstream of a filter being tested; (iii) a second operating mode in which said base unit is configured to receive and analyze a downstream test sample taken downstream of a filter being tested; and, (iv) a clear mode in which residual test sample in said base unit is exhausted from said base unit.   
     
     
         5 . An apparatus as set forth in  claim 4 , wherein:
 (a) said handheld probe further includes an information entry portion allowing a user to enter information relating to the filter being tested from the handheld probe.   
     
     
         6 . An apparatus as set forth in  claim 5 , wherein:
 (a) said handheld probe further includes a display screen for providing a user with information relating to the filter being tested.   
     
     
         7 . An apparatus as set forth in  claim 1 , further including:
 (a) at least a first conduit for electrically coupling said probe to said base unit; and,   (b) at least a second conduit for directing a test sample received by said probe to said base unit for analysis.   
     
     
         8 . An apparatus for testing a filter in situ, said apparatus comprising:
 (a) an in situ filter test unit for analyzing a test sample, said in situ filter test unit being configured to operate in at least a first operating mode and a second operating mode, in the first operating mode said in situ filter test unit being configured to receive an upstream test sample taken upstream of a filter being tested, in the second operating mode said in situ filter test unit being configured to receive a downstream test sample taken downstream of a filter being tested, said in situ filter test unit further being configured to analyze at least one of the downstream test sample and the upstream test sample to determine if the filter being tested is operating satisfactorily without removing the filter being tested from a normal operating position; and,   (b) said in situ filter test unit being configured to automatically initiate a clear mode in which residual test sample in said in situ filter test unit is exhausted from said in situ filter test unit when an operating mode of said in situ filter test unit changes.   
     
     
         9 . An apparatus as set forth in  claim 8 , wherein:
 (a) said in situ filter test unit includes a manifold having at least three entry ports and at least one discharge port, said at least three entry ports include an upstream test sample entry port, a downstream test sample entry port and a clean air entry port; and,   (b) said in situ filter test unit further includes valve means for selectively opening said upstream test sample entry port, said downstream test sample entry port and said clean air entry port.   
     
     
         10 . An apparatus as set forth in  claim 9 , further including:
 (a) said in situ filter test unit includes a base unit having a photometer and a handheld probe operably connected to said base unit, said manifold and valve means being disposed in said base unit, said handheld probe being electrically coupled to said base unit to activate said valve means to selectively open said upstream test sample entry port, said downstream test sample entry port and said clean air entry port.   
     
     
         11 . An apparatus as set forth in  claim 10 , wherein:
 (a) said valve means includes a plurality of solenoid valves connected to said manifold.   
     
     
         12 . An apparatus as set forth in  claim 11 , wherein:
 (a) said valve means includes three solenoid valves, each of the three solenoid valves are connected to one of said upstream test sample entry port, said downstream test sample entry port and said clean air entry port to open and close the corresponding entry port.   
     
     
         13 . An apparatus as set forth in  claim 12 , wherein:
 (a) said base unit is configured to automatically open the solenoid valve connected to said clean air entry port upon at least one of the following conditions occurring: (i) said upstream test sample entry port goes from an open state to a closed state; and, (ii) said downstream test sample entry port goes from an open state to a closed state.   
     
     
         14 . An apparatus as set forth in  claim 12 , wherein:
 (a) said base unit is configured to operate in an upstream test sample mode in which said base unit analyzes a test sample taken upstream of the filter being tested and a downstream test sample mode in which said base unit analyzes a test sample taken downstream of the filter being tested, said base unit is configured to automatically open the solenoid valve connected to said clean air entry port when said base unit changes between said upstream test sample mode and downstream test sample mode such that if the base unit is operating in one of the upstream and said downstream test sample modes and is manipulated to act in the other of the upstream and downstream test sample modes said clean air entry port is opened to exhaust residual test sample in the base unit prior to operating said base unit in the other of the upstream and downstream test sample modes.   
     
     
         15 . An apparatus for testing a filter in situ, said apparatus comprising:
 (a) an in situ filter test unit for analyzing a test sample, said in situ filter test unit being configured to operate in at least a first operating mode and a second operating mode, in the first operating mode said base unit being configured to receive an upstream test sample taken upstream of a filter being tested, in the second operating mode said base unit being configured to receive a downstream test sample taken downstream of a filter being tested, said base unit further being configured to analyze at least one of the downstream test sample and the upstream test sample to determine if the filter being tested is operating satisfactorily without removing the filter being tested from a normal operating position; and,   (b) said in situ filter test unit being configured to allow a user to perform noise suppression on at least one of the downstream test sample and the upstream test sample, said in situ filter test unit further being configured to allow the user to vary noise suppression.   
     
     
         16 . An apparatus as set forth in  claim 15 , wherein:
 (a) said in situ filter test unit is configured to allow the user to perform noise suppression at least in part by data point moving average.   
     
     
         17 . An apparatus as set forth in  claim 16 , wherein:
 (a) said in situ filter test unit is configured to allow the user to select between a plurality of different data point moving averages to perform noise suppression.   
     
     
         18 . An apparatus as set forth in  claim 17 , wherein:
 (a) said in situ filter test unit is configured to allow the user to select from 30 to 120 data point moving averages to perform noise suppression on an upstream aerosol test sample reading.   
     
     
         19 . An apparatus as set forth in  claim 18 , wherein:
 (a) said in situ filter test unit is configured to allow the user to select from 10, 20 and 30 data point moving averages to perform noise suppression on a downstream aerosol test sample reading.   
     
     
         20 . An apparatus as set forth in  claim 19 , wherein:
 (a) said in situ filter is configured to prohibit noise suppression when the in situ filter is testing a downstream sample taken downstream of a filter being tested.