Star delta starters.

[Derlyn]

I've been out of the industrial / commercial scene for 30 years now and haven't put a foot into a factory for at least the last 25 years. Only been doing domestic work.

The other day, whilst at a supplier, I happened to hear someone complaining about how often the soft starter on one of their pumps goes faulty and it's costing a fortune to keep the pump going.

I asked why they don't just use a star delta starter. Apparently they will lose their licence if they do not use soft starters. Not allowed to use star delta starters. They are in the alluvial diamond mining industry.

Has there been some or other law introduced that bans the use of star delta starters ?

[GCE]

Think has more to do with Eskom max demand program that soft starters were introduced
It is also a huge saving on electricity accounts because of the drop on Peak demand

Unless Nersa has introduced something for large consumers

[Isetech]

Back in the 90's when I spent most of my time designing and building control panels and doing automation, We had a basic rule of thumb, if the motor was over 5 kw, star/delta changeover switch gear was used. As PLC's and VSD's became more popular, so we moved to VSD's. Back then the move to VSD's wasnt load management, more for control from remote locations. We built a plant in the Caprivi strip which was controlled from Windhoek, in fact all the plants around the country are controlled from a central location ion Windhoek.

As we move into the renewable market, there is a shift from the old energy saver lamps to led and the same with motor driven products, even fridges and aircons are now rated and controlled by inverters.

An example is aircons, if any of my customers have already upgraded to solar or any form of backup system, we replace or only fit inverter type aircons. An 18000 BTU aircon can now run off a socket outlet and doesnt require a D curve breaker.

So yes I can understand why old star delta switchgear is no longer used. 3 things that make more sense to use a VSD, the cost and the control and no inrush current.

It has been quite a journey watching this industry evolve over the 40 years, from doing my trade test bending steel conduit to throwing twin across the roof. there is only a hnad full of us who can still work on certain machine and switch gear.

You can say what you want, I still have a machine (old lathe) with a manual hand star /delta changeover. it has its challenges but it has out lived all the cheap crap lathes purchased since. Some of the new lathes dont even last 5 years. We spend more time fixing the new lathes than the old. they literally fall apart.