GLOSSARY OF TERMS

ACC-800

A card used with an MSC-800 to control a resolver based motor/drive unit

ACCEL/DECEL

ACE-850

The rate of change to achieve a desired speed. Unit of measure is revs/sec2 .

A card used with an MSC-850 to control an encoder based motor/drive axis

ACM-800

ACM-850

ACTUATOR

AXIS

A controller card used with an MSC-800 to send and receive analog signals

A card used with an MSC-850 to send/receive analog signals

A device which creates mechanical motion by converting various forms of energy to mechanical energy.

An independent motor/drive unit which is controlled by an IIS type controller

AXIS CONTROLLER A card which is used with either an MSC-800 or MSC-850 to control an independent motor/drive unit

CLOSED LOOP

A regulating device in which the actuator position is sensed, and a signal proportional to this position (feed-back position) is compared with a signal proportional to the desired actuator position (command position). The difference between these signals is the error signal. The error signal causes a change in the actuator so as to force this signal to be zero.

COMMAND SIGNAL GENERATOR

A device that supplies a command position signal to an automatic control system. This signal represents the desired motion of the actuator that is required to accomplish a task such as making a part. This signal is usually in the form of an electrical signal.

COMMUNICATIONS The transmission of information from one device to another. The information can take many forms such as command signals, device status and fault conditions.

COMMUTATOR

COMPARATOR

The part of the rotating armature of a motor that causes the electrical current to be switched to various armature windings. The proper sequenced switching of the windings creates the motor torque. The commutator also provides the means to transmit the electrical current from the stationary body of the motor to moving rotor.

A device where the feedback signal is subtracted from the command signal. The difference output of the comparator is called the error signal.

DC DRIVE

ENCODER

FLAG

HOME

HOST

HPL-850

I/O

INDEX

INERTIA

INITIALIZE

INSTRUCTION

An electronic control unit for running DC motors. The DC drive converts AC line current to a variable DC current to control a DC motor. The DC drive has a signal input that controls the torque and speed of the motor.

A type of feedback device which converts mechanical motion into electrical signals to indicate actuator position. Typical encoders are designed with a printed disc and a light source. As the disc turns with the actuator shaft, the light source shines through the printed pattern onto a sensor. The light transmission is interrupted by the patterns on the disk. These interruptions are sensed and converted to electrical pulses. By counting these pulses, actuator shaft position is determined.

A bit in memory used by the programer to evaulate action to be taken. A program branch may be executed depending on the true or false result of a bit test. There are four types of flags supported by the Macroprogram language; axis status flags, I/O status flags, timer status flags and user flags.

A known point of reference frequently referred to as "global zero". Used as a point of reference for absolute positioning.

A computer system whose function is to monitor and coordinate the processes of other devices. A host computer will typically coordinate motion control functions as well as their interaction with other machine processes.

A card used with an MSC-850 multi-axis controller which provides high performance programmable limit switches.

The reception and transmission of information (Input/Output) between control devices. In modern control systems, I/O has two distinct forms. In one, it refers to switches, relays, etc. In the other form, I/O refers to analog signals that are continuous in nature such as speed, temperature, flow, etc.

An index instruction will move the motor shaft an absolute distance relative to the current position.

The measure of an object's resistance to a change in its current velocity.

To execute a series of macro program instructions in order to teach an MSC axis controller an absolute zero reference.

A Macroprogram command to the MSC. All instructions have the following format: have the following format:

label instruction parameters comment

INSTABILITY

IOE-800

Undesirable motion of an actuator that is different from the commanded motion. Instability can take the form of irregular speed or hunting of the final rest position.

A rack containing up to 16 interchangeable I/O modules. The modules may be AC or DC and any combination of input and output.

oan MSC-100 will support up to 2 IOE-800 racks oan MSC-800 will support up to 4 IOE-800 racks oan MSC-850 will support up to 4 IOE-800 racks

This device is also commonly referred to as an I/O Expander.

JOG

LINE SHAFT

MSC TOOLKIT

A jog instruction will move the motor shaft in the specified direction using the predefined speed and accel/decel rates. Once at speed, the motor will continue to jog until commanded to stop.

A shaft rotated by the primary motor drive. The line shaft transmits power from the motor to a load or series of loads. In the multiple load case, the motions of the loads are synchronized to one another because they are driven from a common shaft.

The personal computer based software package used to edit, compile and debug Macroprograms developed for MSC controllers.

MACROPROGRAM A program written in IIS' basic-like language for the MSC family of motion controllers.

MICROPROCESSOR A miniaturized computer system that executes instructions in a sequential manner. The sequential instructions form a control strategy for devices that may be connected to the system.

The sequential instructions are loaded into the microprocessor and can be easily changed or modified. Modern microprocessors are small electronic devices that execute a wide range of instructions at speeds as high as 1,000,000 instructions per second.

MOTOR DIRECTION The direction that a motor shaft is turning is determined by the facing the front of the motor shaft. From this perspective, direction is determined to be clockwise or counter-clockwise.

MAC-800

MCF-850

The main processor within the MSC-800 System Unit, which communicates with the axis controllers as well as external devices such as Personal Computers, I/O Expanders and operator interface devices.

A card used with an MSC-850 controller which provides optional high level functions such as 32K of non-volatile data storage, pseudo axis capability, and programmable limit switches.

MSC-100

MSC-800

MSC-850

MULTI-AXIS CONTROLLER

ON-BOARD I/O

A single axis, programmable servo motion controller

A multi-axis, programmable servo motion controller capable of synchronously controlling from 1 to 8 axes.

A multi-axis, programmable servo motion controller capable of synchronously controlling from 1 to 8 axes. This controller provides more advanced capability than the MSC-800.

A system designed to control more than one actuator. This type of controller allows the actuators to work independently or as a coordinated group to perform more complex tasks.

The I/O module slots that are provided with an MSC System Unit. Each MSC-800 or MSC-850 may have up to 8 onboard input and/or output modules.

OPEN-LOOP SYSTEM A system where a command signal results in actuator movement which is not sensed and therefore not corrected for error. Open loop means no feedback.

OPERATOR INTERFACE

OSCILLATION

A device that allows the operator to communicate with a machine. This device typically has a keyboard or thumbwheel to enter instructions into the machine. It may also have a display device that allows the machine to display messages. An example of an operator interface is the OPI-1.

Undesirable motion of an actuator that is different from the command motion. See INSTABILITY.

PARAMETER

A value required for correct execution of an instruction. Each instruction has a parameter list which is used by the controller to execute the instruction. An example would be the index instruction. The controller needs to know which axis to index and the distance to index.

PLS-850

PERIPHERAL

A rack containing up to 15 output modules for use with either an MCF850 programmable limit switch feature, or an HPL-850 high performance programmable limit switch feature.

Various kinds of devices that operate in conjunction with an MSC controller. Examples of these are PLC's, joysticks, computers, and operator interfaces.

POSITION ERROR The difference between the present actuator position (feedback) and the desired position (command).

POSITION FEEDBACK Present actuator position as measured by a position transducer.

PROGRAMMABLE LOGIC CONTROLLER (PLC)

RESOLVER

ROTOR

(PLC) An electronic device that scans discrete (on/off) type inputs and controls discrete (on/off) type outputs. The relationship between the inputs and outputs are logical statements that are programmable by the user.

A type of feedback device which converts mechanical position into an electrical signal. A resolver is a variable transformer that divides the impressed AC signal into two outputs, referred to as sine and cosine output signals. The comparison of these two signals is used to determine the absolute position of the resolver shaft.

The rotating part of a magnetic structure. In a motor, the rotor is connected to the motor shaft.

SERVO

An automatic control device for controlling large amounts of power by means of very small amounts of power and automatically correcting the performance of the mechanism. Servo systems are closed loop systems.

SERVO AMPLIFIER An electronic device which produces the winding current for a servo motor. The amplifier converts a low level control signal into high voltage and current levels to produce torque in the motor.

SERVO MOTOR

An actuator which converts electrical energy (winding current) to mechanical energy (torque). Servo motor construction is optimized to provide maximum torque with minimum rotor inertia.

SYSTEM UNIT

A system unit consists of an ENC850 Unit Enclosure and MAC850 Main Processor. The Unit Enclosure is a metal cabinet with a motherboard mounted on the back plate. The Main Processor plugs into a connector on the motherboard and provides the processing power to run the operating system and customer application software. The motherboard serves as a multipurpose backplane in which the command bus, on-board I/O bus, two angle busses, and power distribution conductors reside.