|
Click on the cover to read the latest issue of PSB
Affiliate Links
|
Keep motors protected, under control01 March 2004A new generation of electronic protection and control systems can cut wiring and the size of motor control centres with cost benefits for both panel manufacturer and end userElectronic overloads with the ability to communicate data to a higher-level system, such as a programmable logic controller (PLC) have been available for some time. Although these provided satisfactory motor overload protection with advanced diagnostics, they were relatively expensive and offered no cost savings to the end user or panel builder. Six years ago, Siemens took up the challenge of designing a marketdesired solution with the introduction of a new motor protection and control device called the Simocode-DP.
This is an overload relay that integrates with Profibus (an open communication fieldbus system that enables rapid information flow) to protect the system by guarding against overload, phase failure, ground fault, and any current imbalance.
The thinking behind this system is to provide reliable and accurate motor overload protection while being able to reduce costs for the panel manufacturer, design and commission engineers. With savings to be reaped on reduced installation times, benefits can also be passed on to the end user.
Despite the fact that Simocode is more expensive than the standard overload relay, it can still save companies money. It is not just a sophisticated overload relay, but a complete protection and control system.
Siemens says it can replace many other components that were typically installed in the MCC compartment, and the Simocode approach san eliminate the need for devices such as timers, hours run meters, and control relays. This means that the MCC compartment can be smaller, will produce less heat and it makes the MCC easier to ship to site and install.
One major industrial sector that uses Simocode is the UK water industry, which depends on high levels of
reliability in machinery protection for running pump technology. Siemns claims that the use of its application by water process companies has saved them money by reducing the size of their MCCs. The reduction in volume of interconnecting cables also means that installation time is minimised with fewer wiring errors, resulting in decreased civil costs.
In operations where dirty water sewerage is handled, it is essential for pumps to run when required so
reliability is critical. A big concern within the water industry is that in the event of loss of communication, the
process could malfunction leading to disastrous results.
However the intelligence residing within the Simocode unit means that in situations were communication fails, full motor protection and control can still be maintained. Under these circumstances, the unit can revert to “local” or “manual’ mode with startstop control passed to a local operator station, or to an MCC door mounted operators panel.
Earth Tech Engineering Ltd, Tankersley, near Barnsley, Yorks., recently employed the Simocode application on four cyclic activated sludge system (CASS) units in Newry, Northern Ireland.
Paul Searby, Senior Control Systems Engineer for the company, commented, “We standardised on Siemens’ equipment throughout the Newry project, which enabled us to deliver one of the most integrated, cost-effective control systems possible. We’ve ended up with a system that delivers what is required, and has the flexibility to meet increased future demand.”
The uptake by industries around the world has been encouraged by enabling the system to be designed so that it can directly control jobs, whilst having the built-in capability to generate the specific information required for Supervisory, Control and Data Acquisition (SCADA) systems.
This technology, Siemens claims, has raised the parameters for machine protection industry by forcing a
change in practice from previous methods. With 30% space saving and 5% hardware cost saving, the company believes that the Simocode-DP is basic building block in many process industries systems architecture. Contact Details and Archive...Related Articles...Most Viewed Articles... |
|