User Manual

ManualsBrandsDelta ManualsSensorsRMC151

211

212

213

214

215

216

217

218

219

220

RMC70/150 and RMCTools User Manual

RMC70

AA1

-10 to +10V, 4-20mA

AA2

-10 to +10V, 4-20mA

AP2

-10 to +10V, 4-20mA

RMC150

Analog (H)

-10 to +10V, -5 to +5V, 4-20mA

Analog (G)

-10 to +10V

Analog Inputs (A)

-10 to +10V, -5 to +5V, 4-20mA

Universal I/O

-10 to +10V, 4-20mA

Analog Outputs

All the Axis Modules have one analog ±10V Control Output. See the Control Output

topic

for details.

3.12.4. Quadrature Encoder Fundamentals

Quadrature encoders are one of the most common types of encoders. Quadrature encoders

are incremental, meaning that they can accurately measure changes in position, but cannot

provide an absolute position.

Quadrature encoders are often used on motors. They are also commonly used to provide a

reference input, such as the position of a belt, or the position of a board on a flying cut-off

application.

Quadrature feedback is supported by the following modules:

 RMC70: QA axis module, Q1 expansion module

 RMC150: Quadrature (Q) module, Universal I/O module

The RMCs require an RS-422 quadrature signal. This is also commonly referred to as a 5V

differential signal. The RMCs do not support single-ended quadrature signals.

Operation

A and B Signals

Quadrature encoders use two output channels (A and B) to indicate position. Using two

code tracks with sectors positioned 90 degrees out of phase, the two output channels of

the quadrature encoder indicate both position and direction of rotation. If A leads B, for

example, the disk is rotating in a clockwise direction. If B leads A, then the disk is

rotating in a counter-clockwise direction.

By monitoring both the number of pulses and the relative phase of signals A and B, both

the position and direction of rotation can be tracked.

The resolution of quadrature encoders is typically given in Pulses per Revolution (PPR),

also called Lines per Revolution. The RMC feedback sees each rising or falling edge of the

A or B signal as one count

. Therefore, each pulse or line of the encoder will result in four

192 Delta Computer Systems, Inc.