A pressure swing adsorption, PSA, system comprising: a plurality of vessels having one or more layers of adsorbent material therein; a feed gas channel connected to said plurality of vessels via a respective first conduit with a first valve; a waste channel connected to said plurality of vessels via a respective second conduit with a second valve; a product channel connected to said plurality of vessels via a respective third conduit with a third valve; a parallel channel connected to said plurality of vessels via a respective fourth conduit with a fourth valve; a first pressure measuring device configured to measure a pressure within said parallel channel; and a controller configured to monitor the pressure measured by said first pressure measuring device during a PSA cycle performed within said PSA system, characterized in that it further comprises a second pressure measuring device configured to measure a pressure within said product channel, wherein said controller is configured to monitor the pressure measured by said second pressure measuring device during the PSA cycle performed within said PSA system, a purge channel connected to said plurality of vessels via a respective fifth conduit with a fifth valve; and a third pressure measuring device configured to measure a pressure within said purge channel, wherein said parallel channel is an equalization channel, wherein said controller is configured to monitor the pressure measured by said third pressure measuring device during the PSA cycle performed within said PSA system, and wherein said controller is configured to monitor the PSA cycle performed within said PSA system using only (i) the pressures measured by said first pressure measuring device, (ii) the pressures measured by said first pressure measuring device and said second pressure measuring device, (iii) the pressures measured by said first pressure measuring device and said third pressure measuring device, or (iv) the pressures measured by said first pressure measuring device, said second pressure measuring device and said third pressure measuring device. a plurality of vessels having one or more layers of adsorbent material therein; a feed gas channel connected to said plurality of vessels via a respective first conduit with a first valve; a waste channel connected to said plurality of vessels via a respective second conduit with a second valve; a product channel connected to said plurality of vessels via a respective third conduit with a third valve; a parallel channel connected to said plurality of vessels via a respective fourth conduit with a fourth valve; a first pressure measuring device configured to measure a pressure within said parallel channel; and a controller configured to monitor the pressure measured by said first pressure measuring device during a PSA cycle performed within said PSA system, characterized in that it further comprises a second pressure measuring device configured to measure a pressure within said product channel, wherein said controller is configured to monitor the pressure measured by said second pressure measuring device during the PSA cycle performed within said PSA system, a purge channel connected to said plurality of vessels via a respective fifth conduit with a fifth valve; and a third pressure measuring device configured to measure a pressure within said purge channel, wherein said parallel channel is an equalization channel, wherein said controller is configured to monitor the pressure measured by said third pressure measuring device during the PSA cycle performed within said PSA system, and wherein said controller is configured to monitor the PSA cycle performed within said PSA system using only (i) the pressures measured by said first pressure measuring device, (ii) the pressures measured by said first pressure measuring device and said second pressure measuring device, (iii) the pressures measured by said first pressure measuring device and said third pressure measuring device, or (iv) the pressures measured by said first pressure measuring device, said second pressure measuring device and said third pressure measuring device.