Power supply removes intermediate bus

Edited by the Electronicstalk editorial team Oct 26, 2007

The Puls Dimension QTD20 power supply can be connected directly to the intermediate DC bus, removing the need for a separate mains or low-voltage supply for control equipment.

Puls UK has released the QTD20.241 DIN-Rail power supply for use with AC motors and drives.

At only 65mm wide and offering 24V DC at 20A this 95% efficient Din-Rail power supply uses existing system power to provide secure DC for control systems.

Modern machines typically use maintenance-free AC motors that are controlled by frequency convertors or servo amplifiers.

Such controllers have an intermediate DC bus to which all individual drives are connected.

The Puls Dimension QTD20 power supply can be connected directly to the intermediate DC bus, removing the need for a separate mains or low-voltage supply for control equipment.

In the event of a mains failure, the QTD20 uses the power from the DC-bus capacitors, which are charged from the kinetic energy of the motor until the motor has come to a complete stop.

This ensures that the control equipment and other important peripheral equipment is kept operational long enough for a controlled shutdown to take place.

Intermediate DC-buses are not usually filtered and have high EMI noise superimposed.

The Puls QTD20 has a very robust input stage with an appropriate input filter included.

Additionally, the QTD20 is UL 508 approved and is equipped with input fuses rated and tested for 600V DC applications.

Harry Moore, Managing Director of Puls UK said "Our new QTD20 DIN-Rail power supply makes use of existing system power, simplifying installation and wiring".

"Using the inherent hold-up capacity of the drive power is a feature of the QTD20, simplifying system design and ensuring safe operation".

Key features include 600V DC input voltage optimised for intermediate DC-busses of drive systems, efficiency up to 95% with 125% peak load capability, an active input transient filter, full output power between -25C and +60C, minimal inrush current, reverse input polarity protection, a DC-OK relay contact, time saving quick-connect spring-clamp terminals and a three-year warranty.