A-B 1746-QV System Overview Synchronized Axes Control Module

What Is the 1746-QV Module?

The 1746-QV module is part of an SLC-based open-loop control

system for controlling the speed and placement of an hydraulic ram.

The module accepts an input from a linear displacement transducer

(LDT) and motion profiles that you program into the SLC processor,

and varies its output in the range of 10V dc. The SLC processor

sends to the module a pair of extend and retract profiles that define

when to accelerate or decelerate hydraulic motion.

What Is an SLC-500 System?

The Allen-Bradley Small Logic Controller (SLC) system is a

programmable control system with an SLC processor, I/O chassis

containing analog, digital, and/or special-purpose modules, and a

power supply. The 1746-QV module interfaces your hydraulic ram

and position-monitoring device (LDT) to the ladder sequence in your

SLC processor. The system can be illustrated as follows:

Why Use This System?

Because you can change the speed of the hydraulic ram with extend

and retract profiles and store additional profiles (recipes) in data

table iNteger (N) files, this control system has these benefits:

• reduced cycle time – you can increase ram speed for faster operation

• reduced or eliminated pressure spikes and water-hammering for

smoother operation and less wear and tear on the machine –

you can profile accelerations and decelerations of the hydraulic ram

• energy savings – you can match the speed of the hydraulic pump

to the force that you need

• faster new-part change-over – you can store your setups and

minimize mechanical re-adjustments between parts

How Does It Work?

The 1746-QV module executes the extend and retract profiles that you

load to control the motion of the hydraulic ram. You can program up

to seven different voltages over the length of travel in both the extend

and retract directions to control how the ram accelerates or decelerates.

Each position setpoint triggers a corresponding voltage output in the

range of –10V to +10V dc that translates into speed. The LDT

provides high-speed position updates to the module for consistent and

repeatable motion.

What Are Typical Applications?

Use the 1746-QV module in an SLC-based system for low-cost

control of:

• hydraulic machinery

• simple (non-CNC) hydraulic presses

• diecasting machinery

• welder placement

• pneumatic actuators for clamping or placement

In addition, the module is designed to support standard proportional

amplifiers and retrofit into most existing hydraulic systems.