Emerson 400276-01 User Manual

525 PROGRAMMABLE

MOTION CONTROLLER

INSTALLATION and

OPERATION MANUAL

P/N 400276-01

Rev.: A2

Date: August 25, 1997

© 1997 EMERSON Motion Control. All Rights Reserved.

525 Programmable

Motion Controller

Information furnished by EMERSON Motion Control is believed to be accurate and reliable. However, no
responsibility is assumed by EMERSON Motion Control for its use. EMERSON Motion Control reserves
the right to change the design or operation of the equipment described herein and any associated motion
products without notice. EMERSON Motion Control also assumes no responsibility for any errors that
may appear in this document. Information in document is subject to change without notice.

P/N 400276-01

Rev.: A2

Date: August 25, 1997

© 1997 EMERSON Motion Control. All Rights Reserved.

525 Programmable Motion Controller

ii

© 1997 EMERSON Motion Control. All Rights Reserved.
Document Number: 400327-00
No part of this manual may be reproduced by any means without the written permission of EMERSON

Motion Control.
EMERSON Motion Control is a registered trademark of EMERSON Motion Control.
Printed in U.S.A.
July 1997, Revision A1

Disclaimer:

The installer is responsible for any damage that may occur when upgrading
FX Drives in the field.

This document has been prepared to conform to the current release version of the FX Positioning Drive
system. Because of our extensive development efforts and our desire to further improve and enhance the
product, inconsistencies may exist between the product and documentation in some instances. Call your
customer support representative if you encounter an inconsistency.

iii

Introduction

525 Programmable Mo-

Product Overview

The Emerson Motion Control 525 PMC (Programmable Motion Controller) is a
complete closed-loop position controller for use with external analog or digital servo
drives in positioning applications. The 525 PMC accepts all current PCM
Application Modules and peripherals in the Emerson Motion Control FX product
line.

Figure 1 Typical 525 PMC Configuration

The 525 PMC outputs an analog velocity command signal and accepts encoder
feedback signals closing the position loop around an external servo drive.

525 Programmable Motion Controller

The 525 PMC uses PCX Version 6.02 or newer for setup, calibration and
programming. A single PCX program can control multiple axes including a mixture
of Positioning Drives and 525 PMC's.

All 525 PMC gain settings are pre-programmed and can be changed from PCX
software (see PCX 6.X Operators Manual P/N 400240-01). A fine position loop
adjustment is provided on the front of the 525 PMC which allows you to fine tune
the system without requiring a personal computer. The servo amplifier and the 525
relationship is determined by a programmable command voltage to RPM ratio with
a default of 10 volts = max RPM of the motor.

The 525 PMC is designed accept a series of application modules called "PCM"
modules. The PCMs are attached by simply plugging them onto the front of the 525
PMC. The PCM modules are designed to share the 525's power supply and include
12 additional optically isolated inputs/outputs (making a total of 24).

The 525 PMC can operate with either 115 or 220 VAC single phase power (switch
selectable). The 525 PMC includes a pulse follower mode (see "Operating Modes"
on page 4).

External Drive Interface

The 525 PMC is designed to be used with common servo drive systems. A perfect
match is a servo drive that has a +/- 10 volt input equalling +/- maximum velocity
and an encoder feedback signal that equates to the actual motor position.

Command Signals

The 525 PMC command signal tells the servo amplifier (by the polarity and level of
the command) how fast and in what direction to move. The feedback position is
compared to the command position to determine whether the motor is doing what
it has been commanded to do. If an error between command and feedback exists,
the error is multiplied by a programmable gain and used to add or subtract the
command to the amplifier.

The input velocity scaling of the external drive must match the 525 PMC command
output scaling. By using the PCX system calibration screens, you can modify the
Calibrated Velocity and the Calibrated Velocity Command Voltage. Using these
values the 525 PMC is able to provide the proper command voltage with minimum
error.

Some drives have little or no speed regulation below 10% to 40% of the command
signal. Although this may be ok for simple velocity control, the 525 PMC must
control the speed from zero to ± full velocity. Without low speed regulation the 525
PMC cannot accelerate to the commanded speed without gross positional errors and
a possible fault condition.

The ability to accelerate or decelerate a load is a function of the external drive. The
525 PMC will linearize the velocity profile through positional feedback control. The
overall performance of the 525 PMC is tied directly to the drive's performance. The
525 PMC's ability to generate a command signal in excess of any particular drive's
capability does not mean that the 525 PMC can improve that drive's capability to
produce torque.

Special compensation of a specific amplifier may be required to accommodate a
specific application or load mismatch. Consult with the amplifier manufacturer for
specific details.

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Operating Modes

The 525 PMC offers three standard modes of operation: Indexing, Pulse and
Analog.

Indexing Mode

The indexing mode allows up to thirty-two different indexes or positions to be pre­programmed and stored in non-volatile memory. These indexes and other
commands such as stop and jog are selected by the drive's input/output (I/O) lines
from devices such as PLCs or operator push buttons. I/O connections can be used
for stand alone operation or in conjunction with one of the two control modes.

Another powerful feature of the indexing mode allows ASCII serial commands to be
received through the standard RS423 serial interface. This interface port allows
you to down-load new positional data such as distance, velocity, position etc.. The
ASCII serial commands work with the RS232C serial interface on an IBM (or
compatible) personal computer (PC) or programmable logic controller (PLC) with
an ASCII or basic module.

Pulse Mode

In the pulse mode the 525 PMC responds to a pulse train representing externally
generated incremental position change commands. These commands are normally
in the form of CW or CCW direction pulses. This mode is commonly used to when
replacing stepper motors.

Introduction

Analog Mode

In the analog mode the 525 PMC responds to a conventional +/- 10 volt signal. Most
variable speed drives and servo amplifiers on the market today receive commands
via analog input.

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525 Programmable Motion Controller

4

Installation

525 Programmable Mo-

Installation Overview

The following installation requirements, methods and procedures are provided to
ensure reliable and trouble free installation and operation of your Emerson Motion
Control 525 PMC.

The methods and procedures are outlined on the following pages and include site
requirements, safety, power and fusing requirements, wire and transformer sizing,
noise suppression and I/O wiring.

The installer has the responsibility to comply with the safety requirements of the
system. This includes installing the system with an appropriate master interlock
switch for emergency shut down, using the proper wire and if necessary,
transformer sizes to fit the system. This section will provide you with the
information to complete a trouble free installation.

Safety

The user is responsible for providing emergency interlock switches that will
remove AC power from the system any time the equipment is not running, or
when the emergency stop is activated. This is to eliminate the possibility of
electrocution or unwanted movement of the motor. The safety ground
connections should only be disconnected for servicing, and only after all AC
power has been removed. Even after the removal of AC power, there is a
possibility of stored energy in the drives that must be dissipated before
servicing. Failure to follow proper safety procedures can cause death or
serious injury.

Disconnecting AC power does not immediately remove the stored energy in the bus
capacitance and the external drive may continue to operate until this energy is
dissipated. The time it takes to dissipate the energy in the bus capacitance greatly
depends on the current being drawn out of the capacitors.

525 Programmable Motion Controller

Figure 1 External Disconnect Example

AC Input Line

The AC line voltage of the input power must be within the specified range and free
of voltage transients that exceed this range. If this is not the case, additional AC
line conditioning may be required.

The AC input lines are connected to the 3-position terminal strip (L1, L2, GND)
located on the bottom plate of the 525 PMC. Power to the 525 PMC and the external
drive must be applied at the same time. To ensure proper operation after removing
power, wait a minimum of 10 seconds before re-applying power.

NOTE: The application of AC power to the 525 PMC must be

Grounding

The 525 PMC is internally grounded. The primary function of proper chassis
grounding is to ensure that the earth ground is connected to the AC ground input
of the chassis. Ground connections must be made from the chassis ground terminal
on each piece of equipment to a unique single point ground.

simultaneous with application of AC power to the controlled
external drive.

Connections should use the same gauge wire as the power input wire to the device
and not be shared with any other equipment. The motor cable should contain a
motor frame ground wire of at least the same gauge as the armature power
conductors.

All electrical cabinets and machine elements must be ground bonded together. 2
shows a typical grounding arrangement. To ensure proper grounding techniques,
please observe the recommendation of the IEEE Ground Book, ANSI Standards,
and the National Electrical Code.

2

Installation

Figure 2 System Grounding illustration

Electrical Noise

If any sensitive electronic equipment (i.e. digital computer, test equipment, etc.) is
operating on the same line as the 525 PMC additional EMI/RFI filtering may be
required to reduce the effects of conducted noise. Effects of electrical noise on the
electronic equipment is greatly reduced when the techniques outlined below are
closely followed.

1. Do not run low power control signals and high power wiring in the
same raceway.

NOTE: If mixing wires cannot be avoided, then the low voltage control

input and output wiring must be shielded. The shield for these
wires should only be connected to ground at the source end of
the cable.

2. Connecting both ends of a shielded cable to ground may cause a
ground loop condition.

3. Keep all wires in the system as short as possible, with consideration
for troubleshooting and repair.

4. Follow the recommended grounding arrangements.

5. Suppression devices should be used on relays and coils as outlined in
the following section.

6. If control signal and high power wiring must cross, make sure they
cross at a 90 angle.

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525 Programmable Motion Controller

Magnetic Coil Noise

All relay coils, solenoid coils, electrical brakes and similar devices must be
suppressed. The placement of the noise suppressor should be as close to the coil as
possible.

In the case of DC coils, a diode is installed across the coil in a direction that will
cause the voltage transient to be supressed by the diode.

Figure 3 Magnetic Coil Noise (DC Line)

In the case of AC coils a capacitor and resistor are installed across the coil to
suppress the unwanted transient.

Figure 4 Magnetic Coil Noise (AC Line)

The specific values of resistance and capacitance may vary depending on the
inductance of the coil. Consult the relay manufacturer for the proper values to use.
These suppressor networks greatly extend the life of the contacts controlling the
coil because the transient energy, which can easily reach 1000 volts, shunts
through the suppressor rather than arcing across the controlling contacts as they
open.

I/O Wiring Layout

All signals to and from the 525 PMC must be connected with an electrical grade
insulated wire to withstand the application environment. Although each signal
input and output was designed for high noise immunity, careful wire routing within
the enclosure will help cut down electrical noise between I/O lines and noise
emitting conductors.

High voltage (>50V) must be separated from low voltage wiring in order to
minimize cross talk. High voltage signals should be run in a separate conduit
physically separated from the low voltage signals. In addition, any high current
carrying conductors should be twisted to minimize noise emission.

Conductor lengths should be as short as possible to reduce noise and losses in the
system. Input/output wiring can be safeguarded against noise by a shielded cable.
Brake leads should be treated as power conductors and run within the armature
conduit or raceway.

Shielding

When shielding cable it is important to know the difference between the types of
shielding available. A braid shield is the most effective way to minimize the effects

4

of Electro-Magnetic Interference (EMI). A foil shield is the most effective way to
minimize Radio Frequency Interference (RFI).

A cable that provides both types of shielding is preferred, however, a braided shield
alone will usually provide adequate protection. To reduce chances of ground loops,
shields should be grounded only on one end, preferably at the signal source.

Selecting An Enclosure

The Emerson Motion Control 525 PMC is designed for the industrial environment.
However, no sophisticated electronic system can tolerate certain atmospheric
contaminants such as moisture, oils, conductive dust, chemical contaminants and
metallic particles. Therefore, if the 525 PMC is going to be subjected to this type of
environment, it must be back mounted verticality in a metal NEMA type 12
enclosure. Proper ventilation and filtering must also be provided. If the equipment
environment is above 80 F, cooling should be considered.

Enclosure Size

The size of the enclosure will determine how long it takes the temperature inside to
rise. It will also affect the thermal transfer of the enclosure. Normally, the larger
the enclosure the better the thermal transfer. Thermal transfer is also affected by
venting, forced air cooling, and the enclosure material.

Installation

5

525 Programmable Motion Controller

Encoder Feedback

The 525 PMC utilizes an xe "ENCODERS:Incremental Encoder" incremental
encoder as the feedback device from the motor. The type of encoder used must have
two complimentary channels electrically spaced 90 from each other. These encoder
channels are usually designated as CHA and CHB. To fully utilize the motion
controller, the encoder must have a third complimentary channel that has a once
per revolution output called Mark, or Index.

Emerson Motion Control can provide two encoder configurations for use with the
525 PMC.

Figure 5 Encoder Model SDC-15-1, 1024 Line Density

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Installation

NOTE: The use of a flexible coupling is required between the encoder

and the motor shaft.

Figure 6 Encoder, Model SDC-25-1, 1024 Line Density

NOTE: The use of a flexible coupling is required between the encoder

and the motor shaft.

Encoder Sine Wave Signals

A graphic illustration of the encoder signals from either the SDC-15-1 or SDC-25-1
is shown below.

Figure 7 Typical Encoder Signals - Sine Wave Output

A line on an encoder would be 360° of signal change of either A or B.

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