SU0005344 ENG DES PLN - Laserfiche WebLink

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__Pwi The PLC is a modular style unit with individual input, output and logic control modules that are of a "Plug and Play" design. If a single module fails it can be replaced and the logic module will control it automatically. In the event the logic module has a failure, a new module can be plugged in, pre-loaded with the program or it can be programmed via the internet. An option also available is our redundant PLC which always has two systems monitoring the entire process independent of each other and in the event of one failing; the back-up unit takes over and sends an alarm out notifying of the failure. The entire process is tied into a customer supplied static IP address and has a distinct URL on the internet. In the event of an alarm or malfunction, alarms will be sent to user specified email addresses, cell phones, pagers, PDA's or a full time alarm monitoring station, such as ADT or a police dispatch center. This process allows the operator to be notified, either directly or by others monitoring the plant. The operator will perform the standard functions of acknowledging the alarm; determine its cause, and resolving the problem. For example if the filtered effluent exceeds 2 NTU, the DAF effluent will be diverted from the intended irrigation use to the existing underground injection well. This can be done remotely or locally when the operator receives an alarm sent by the PLC from the monitoring of the inline turbidity meter. After the filtered effluent is diverted, the operator will investigate the reason causing the failure of filtration on site and take the required action(s) to restore the system to full functionality. Additionally, a remote telephone dialer could be used to send various levels of alarms via a customer supplied telephone (land line or cell phone). There are four outputs dedicated to alarms in the standard package. These can drive lights, horns or strobes if local annunciation is required. The remote dialer can also be a secondary back-up in the event of internet failure. The PLC trends all of the critical processes and values, and stores them for documentation of run time of the equipment and monitored levels, i.e. pH, DO, turbidity, flow, etc. Wine Cup Motor Coach Resort WWTP Page 10 of 10 8/22/2007 Preliminary Design Report