Another disaster averted!

When we received a call at APDS Ltd out of hours one Tuesday evening from a Sewage Treatment Works with a reported failed inverter on one of their Return Activated Sludge (RAS) Pumps, we arranged for our local engineer to attend and investigate first thing on the Wednesday morning.

He quickly ascertained that the 15kW Control Techniques Commander VSD had a failed output stage. Due to the age and size of this VSD, along with the need to have the RAS pump operational again ASAP, repair was eliminated as an option. Instead, after completing an pre-installation survey, it was decided that APDS would supply, install and commission a water industry specific ACQ580-01 to replace the faulty CT drive. Our engineer returned the following morning armed with an ACQ580-01 and seamlessly carried out the replacement, ensuring that the STW would ‘not be caught short’ less than 48 hours after the first call.


If your plant has critical VSD’s or softstarters, do you have a plan for if or when they fail?

If not, contact us at to arrange for a lifecycle assessment to be carried out and
a plan put in place for the continued resilience of your key assets.