Water & Wastewater Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/1040774
10 | NOVEMBER 2018 | WWT | www.wwtonline.co.uk The Talk: opinion EXPERT VIEW SPONSORED BY ABB STUART FOSTER, UK WATER MANAGER, DRIVES, ABB Five things you (probably) don't know a variable speed drive can do Many people are unaware of the capabilities of a variable speed drive, beyond the basic task of making a motor go faster and slower M ost users buy a variable speed drive (VSD) to start/ stop a motor and make it go faster/ slower. Very few know about the other functionality within their drive. Yet here in an insight into five things that you probably didn't know a VSD can do: 1. Adaptive programming – Some VSDs contain a feature called adaptive programming. The programme is built with standard function blocks included in the drive firmware and can be used to customise the operation of a VSD. This includes helping to resolve technical challenges retrospectively. For instance, a UK water utility tried an emergency stop shut down on a new large set of pumps, but the harshness of the stop caused the building to vibrate. Using adaptive programming, the drive was coded to detect stop situations and come to rest more steadily. Without adaptive programming the cabinets would have needed to be re-wired and the project delays would have been hugely expensive. 2. The hidden gems inside – O‹en panel builders or OEMs will purchase a host of components without realising that they are already contained in the VSD. For instance, a panel builder will need thermostats for controlling cabinet fans to save standby losses, timer relays, contactors, door-mounted HMIs and a mini PLC to control the system to behave at different times of the day. Yet all these components, and more, are o‹en not needed as they are already built within the VSD. 3. Smart safety – Today's VSDs offer several features and functions that increase safety for plant operatives. One example is safe torque-off (STO). This is a SIL 3 PL e stop function that is both safer than, and avoids the need for, a contactor, for example in an emergency stop situation. With some drives, STO can also be supplemented with additional drive safety functions, such as safely-limited speed, which prevents motors from exceeding a defined speed limit, and safe stop. The arrival of Bluetooth- enabled keypads, meanwhile, is transforming the maintence of VSDs in hazardous or hard-to-reach areas. By downloading the manufacturer's app to a smartphone or tablet, the user is able to wirelessly connect to multiple drives and execute any task they could accomplish by directly accessing the keypad, including commissioning, tuning and maintenance. Bluetooth is typically functional up to 75 metres from the drive in any direction. This reduces the need for maintenance staff to enter confined or hazardous areas. 4. Automatic back-up – As well as two manual backups, some VSDs perform an automatic backup regularly, so settings are always stored. Should a problem occur, the latest parameter settings can be downloaded via the drive's keypad and reinstalled in minutes. This avoids having to recommission the drive, thereby minimising downtime. 5. Improving maintenance – Today's VSDs can point the way to developing a preventive maintenance strategy for pump applications. This is achieved by the drive's ability to monitor key parameters – such as temperature, current and torque – in real time. Using this data, in conjunction with process variables such as flow or pressure, the end user is able to determine the efficiency of the system and also identify potential problems before they occur. "O en panel builders or OEMs will purchase a host of components without realising that they are already con- tained in the VSD." privatisation. The treatment of debt at Thames Water by Macquarie Bank might be of interest under this heading. In his party conference speech on 24 September 2018, John McDonnell also referred to the 100th anniversary of the party adopting Clause IV of its constitution, declaring: "I say the Clause IV principles are as relevant today as they were back then." Part of Clause IV of the Labour Party constitution as adopted in 1918 committed the party "to secure for the workers by hand or by brain the full fruits of their industry and the most equitable distribution thereof that may be possible upon the basis of the common ownership of the means of production, distribution, and exchange, and the best obtainable system of popular administration and control of each industry or service." The proposals for the water industry therefore need to be read with the Labour Party Consultation Paper: Democratic Public Ownership, which introduces a wider debate on public ownership of key enterprises and the form it should take. They should also be considered alongside the party's wider proposals for Inclusive Ownership Funds ('IOFs'), to be mandatory for companies employing more than 250 people, with 1% of ownership of shares transferred to IOFs per year, to a maximum of 10% IOF shareholding; workers in the companies to receive up to £500 in dividends per annum, with the Treasury controlling the use of the remainder. Seen in that light, even nationalisation of the water, energy, rail industries and Royal Mail may not be the most radical of the Labour Party's proposals for re-balancing the economy. To complete the picture for the water industry, the legislation would need to provide a new model for economic regulation, but also to construct a new basis for environmental regulation, as EU environmental laws, which have driven much of the investment of privatised water companies in environmental improvements, would need to be re-enacted following Brexit. Labour plans commit the party to the 'highest environmental standards', so this remains an important component where further detail will be essential. On the economic plans, even some commentators on the FT (Jonathan Ford, 18 February 2018) caution against private companies simply dismissing nationalisation as impractical, and argue that more needs to be done to make an overcomplicated regulatory model work. William Wilson is a barrister, an environmen- tal and energy lawyer, and Consultant Editor, Halsbury's Laws, Water & Waterways. He can be contacted at info@wyesideconsulting.com