Main Duties and Responsibilities of the company
CSL were appointed as the Main Contractor for this project and fulfilled the roles of PSDP and PSCS.
The following works were completed.
- Installation and commissioning of 400kva Generator on skid, complete with all changeover switchgear
- Installation and commissioning of 2No 110kw VSD units in separate kiosk.
- Installation and commissioning of Allen Bradley PLC and HMI for control; designed to maximise pump run time and protect equipment.
- Installation of new cabling ducts, external site lighting and key switch at entrance.
- Installation of communication link to main SCADA system and a SMS alarm system.
- All electrical, mechanical, automation/control, building, and civil engineering work.
- Civil works which included ducting, plinths, coring and reinstatement
Other relevant information
The pumping station had been installed as part of the main drainage works for Carlow to provide Stormwater pumping to the Barrow river.
The 2No. 80KW pumps had originally been installed with Soft starts but in storm condition it was found that the pump switchgear was subjected to severe and rapid ON/OFF starting. It was decided to upgrade to VSD’s at the same time as installing a standby generator. Though the pumps are 80KW, they are 12pole motors so the VSD selected were 110KW units. The VSDs’ speed is controlled by the PLC. The PLC uses a PID (Proportional Integral Derivative) loop to adjust the speed of the duty pump so that the actual level in the sump matches a set level (adjustable setpoint). As the level increases in the sump the speed of the pump increases; the speed of the pump decreases as the level declines in the sump. The duty pump will operate under PID control for a predetermined time (adjustable setpoint). When the time has elapsed, the duty pump will run at full speed and empty the sump.
The generator is mounted externally on a plinth in front of the control panel. The generator was sized to allow both pumps to run together. In severe storm conditions both pumps are required to match the inflows. However, the ESB transformer for the site isn’t large enough to allow both pumps operate together. CSL implemented a system that allows the operator to select generator power when both pumps are required to run together. The system is protected by an electrical interlock and password so that the pumps cannot be inadvertently started when ESB power is selected.
A protective canopy and Perspex windshield was later added to protect the panel and operator from Rain when kiosk doors are open.
Installation of Generator
