Five things you (probably) didn’t know about a variable speed drive:

5 things you didn't know about a VSD

Most 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. Neil Keenan, service manager for ABB authorised value provider, EDC (North East) Ltd gives an insight.

1. The hidden gems inside - Often 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, doormounted HMIs and a mini PLC to control the system to behave at different times of the day. Yet all these components, and more, are often not needed as they are already built within the VSD.

2. 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.

3. Intuitive keypad - Today’s VSD keypad offers 21 variables, displayed via graphs, charts and meter readings that speak the language of any application. There is no need for any analogue meters as the keypad has a view that looks like an analogue moving iron meter, scaled and labelled in the correct customer units. The keypad negates the need for cabinet furniture such as start/stop buttons, as these can be programmed into the keypad. The VSD can be customised to present the language of the application or industry and change warnings and trips into plain, simple language – “Pump 2 failed in Bay 6, top floor”. An OEM using this facility can now dispatch a true customer ready drive package.

4. Automatic back-up - As well as two manual backups, the drive can take 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. It’s not all about energy – While the energy saving benefits of a VSD are well documented, quite often the impact a drive can have on improving productivity are less well known. Among the features that impact productivity are: the ability to catch spinning loads, power loss ride through, stall and load fault detection, remote monitoring and torque boost. VSDs provide the solution to all of these issues and more.

Copyright of ABB. Previously published in Drives & Controls magazine.