Overview
Recently, we were involved in the Deep Tunnel Sewerage System (DTSS) PUB project, and we were tasked to do a sewage diversion system for a 22kW submersible pump in a high traffic flow location in central downtown.
Soft-starter was chosen as the starting method due to it’s low starting torque. As a flexible tubing was used for the diversion, a DOL system might cause the pipe to burst due to the surge in pressure when starting. An SMS Alert system was also introduced to ensure that when the system malfunctions, the operator will receive an SMS alert. The SMS Alert system was also required to have uninterrupted power supply(UPS) for more than 8 hours during a power failure.
Heavy duty float switches were used as well, these float switches are designed to ensure that the scum in the sewage does not affect the operation of the switch. In some cases, regular float switch will get stuck in scum and is unable to tilt upwards. Hence causing a systematic failure.
More on the Deep Tunnel Sewerage System (DTSS) can be found here: