Rotary switches use Gray encoding for accuracy

Edited by the Electronicstalk editorial team Feb 16, 2007

Lorlin Electronics has brought out a range of 8-position coded rotary switches for control and programming functions.

Lorlin Electronics has brought out a range of 8-position coded rotary switches for control and programming functions.

The 8-position GCK family of Gray-coded switches is more accurate than the existing standard BCK series which offers 16 positions of binary encoding or complementary hexadecimal versions.

The contacts in conventional binary coded switches produce a standard binary count as the contact disc rotates.

However, this has the drawback that if the disc stops between two adjacent sectors, or the contacts are not perfectly aligned, it can be impossible to determine the angle of the shaft and an incorrect code may be read.

The 8-position GCK family of switches uses Gray encoding to boost accuracy.

Gray encoding is a system of binary counting in which two adjacent codes differ in only one position.

With Gray coding switching transitions only one of the contacts has to change its state from on to off or vice versa.

This avoids the potential of incorrect code sequences that may be possible from conventional binary coded mechanisms.

The BCK and GCK offer contacts rated at 150mA at 50V AC/DC, operational life greater than 10,000 cycles, operating temperature range - 30 to +85C, 250V AC proof voltage and contact resistance of less than 50mOhm.

Customers may specify additional features such as imperial or metric spindle diameter, length of spindle, required mounting thread, spindle flat and angle, adjustable mechanical stop or no stop and silver or gold contacts.

Dan Walker, Sales Manager for Lorlin comments: "Our binary and Gray-coded switches offer designers the opportunity to fit the most appropriate coding system for their particular application".

"We have seen more than 10% growth in these products and we believe that having design and manufacture in the UK allows our customers to get the right product, first time and on time" The Lorlin BCK and GCK switches are available directly from the factory as well as from a large distributor network.