Rockwell Automation 1734-VHSC24 User Manual

Very High-Speed Counter Modules

1734-VHSC5 and 1734-VHSC24

User Manual

Important User Information

SHOCK HAZARD

Solid state equipment has operational characteristics differing from those of electromechanical equipment. Safety Guidelines for the Application, Installation and Maintenance of Solid State Controls (Publication SGI-1.1 available from your local Rockwell Automation sales office or online at http://literature.rockwellautomation.com) describes some important differences between solid state equipment and hard-wired electromechanical devices. Because of this difference, and also because of the wide variety of uses for solid state equipment, all persons responsible for applying this equipment must satisfy themselves that each intended application of this equipment is acceptable.

In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment.

The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or liability for actual use based on the examples and diagrams.

No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or software described in this manual.

Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation, Inc., is prohibited.

Throughout this manual, when necessary we use notes to make you aware of safety considerations.

WARNING

IMPORTANT

ATTENTION

BURN HAZARD

Identifies information about practices or circumstances that can cause an explosion in a hazardous environment, which may lead to personal injury or death, property damage, or economic loss.

Identifies information that is critical for successful application and understanding of the product.

Identifies information about practices or circumstances that can lead to personal injury or death, property damage, or economic loss. Attentions help you:

• identify a hazard

• avoid a hazard

• recognize the consequence

Labels may be located on or inside the equipment (for example, drive or motor) to alert people that dangerous voltage may be present.

Labels may be located on or inside the equipment (for example, drive or motor) to alert people that surfaces may be dangerous temperatures.

POINT I/O, POINTBus, and RSLogix 5000 are trademarks of Rockwell Automation. ControlNet is a trademark of ControlNet International, Ltd. DeviceNet is a trademark of Open DeviceNet Vendor Association, Inc.

Summary of Changes

This publication contains new and revised information not in the last release.

New and Revised Information

See the table for a summary of the major changes in this manual.

Chapter Change

Preface Update of list of publications

Indication that for specifications and safety approval information refer to the installation instructions

2 Addition of Before You Begin section

Addition of attention and warning statements

Appendix A Update on how to configure modules in RSLogix 5000 software

Change Bars

W e marked with change bars (as shown with this paragraph) the areas in this manual that differ from previous editions and indicate the addition of new or revised information.

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Summary of Changes 2

Notes:

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Preface

About the Modules

Install the Modules

Preface

Purpose of This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . P-1

Who Should Use This Manual . . . . . . . . . . . . . . . . . . . . . . P-1

Related Products and Documentation. . . . . . . . . . . . . . . . . P-1

Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-3

Chapter 1

What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 1-1

Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Counter Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Encoder Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Period/Rate Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

Operation of Scalar . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Rate Measurement Mode . . . . . . . . . . . . . . . . . . . . . . . 1-7

New Data Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

Default Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

Operating Mode Features . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

Chapter 2

What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 2-1

Before You Begin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Install the Mounting Base Assembly. . . . . . . . . . . . . . . . . . 2-1

Install an I/O Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Install the Removable Terminal Block . . . . . . . . . . . . . . . . 2-4

Remove a Mounting Base . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Wire the Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Input and Output Data

Chapter 3

What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 3-1

Data Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Detailed Description of Data Table Information . . . . . . . . . 3-2

Stored/Accumulated Channel Data (Input Word 2) . . . . 3-2

Module/Channel Status and Programming Error Codes

(Input Words 3 and 4) . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

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Configure Your Module

Configuration Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

Counter Configuration (Configuration Word 1) . . . . . . . 3-5

Filter Selection (Configuration Word 2 . . . . . . . . . . . . . 3-5

Decimal Position (Configuration Word 3) . . . . . . . . . . . 3-6

Word 4 is reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Time Base and Gate Interval (Configuration Words

5 and 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Scalar (Configuration Word 7) . . . . . . . . . . . . . . . . . . . 3-7

Scalar Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Rollover (Configuration Word 8). . . . . . . . . . . . . . . . . . 3-7

Preset (Configuration Word 9) . . . . . . . . . . . . . . . . . . . 3-7

Safe State Values (Configuration Word 10) . . . . . . . . . . 3-8

Communicate Real Time and Nonreal Time Information. . . 3-8

Chapter 4

What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 4-1

Configuration Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Add the Adapter to Your Network . . . . . . . . . . . . . . . . 4-1

Add I/O Modules to Your Network. . . . . . . . . . . . . . . . 4-2

Set Counter Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Check I/O Status and View/Edit the EDS File. . . . . . . . . . . 4-6

Access Instantiated Instances

Troubleshoot with the Indicators

Configure Modules in RSLogix 5000

Index

Chapter 5

What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 5-1

Use Instantiated Instances . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

Chapter 6

Use the Indicators for Troubleshooting . . . . . . . . . . . . . . . 6-1

Appendix A

What This Appendix Contains . . . . . . . . . . . . . . . . . . . . . . A-1

Understand Data, Connection, and Communication Formats A-1

Configure Your Module. . . . . . . . . . . . . . . . . . . . . . . . . . . A-3

Use the Help Button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3

Work with the Fault/Program Action Dialog. . . . . . . . . . . . A-4

Work with the Counter Configuration Dialog . . . . . . . . . . . A-6

Work with the Output Configuration Dialog. . . . . . . . . . . A-10

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Preface

Purpose of This Manual

Who Should Use This Manual

Read this manual for information about how to install, configure, and troubleshoot your module.

For This Information See

About the Modules Chapter 1 Install the Modules Chapter 2 Input and Output Data Chapter 3 Configure Your Module Chapter 4 Access Instantiated Instances Chapter 5 Troubleshoot with the Indicators Chapter 6

You must be able to use RSNetWorx software or similar configuration software to set up and calibrate these modules. You must have the capability to download and use Electronic Data Sheet files.

We assume you know how to do this in this manual. If you do not, refer to your software user manuals or online help before attempting to use these modules.

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Preface 2

Definitions

The following define the intended operation of the module.

Term Definition

Lead Breakage Typically requires a shunt resistor (across the load) to detect

3 levels of current/input states -

• Open (Wire Off, Device = ?)

• Off (Wire OK, Device Off)

• On (Wire OK, Device On)

This method does not check the input against a time base, only that the device wiring (current loop) is intact.

Missing Pulse Typically uses an input pulse to reset a watc hdog timer (fixed

or programmable HW). This method does detect Lead Breakage, since a broken wire will time-out the watchdog.

Zero Frequency Typically uses an input pulse to calculate an input frequency

and verify it is above an error threshold. This method does detect Lead Breakage, since a broken wire will generate a 0Hz frequency.

Missing Pulse or Zero Frequency will also detect a customer device stuck high or low, since the counter is monitoring for a change in the input state. Currently, the Counter/Encoder Modes do not have Zero Frequency Detection - the A and B inputs are time independent, only looking for input edge changes to increment/decrement the count value.

The Period/Rate and Continuous Rate modes do have Zero Frequency Detection, since the Z input is monitored for Zero Frequency in Firmware (A and B inputs are not used and not monitored).

The Rate Measurement mode inherently has Zero Frequency Detection, since no A pulses in any sample period are = 0Hz (B and Z inputs are not used and not monitored).

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Preface 4

Operational Mode Zero Frequency Detection Input Monitored

Counter No None Encoder No None Period/Rate Yes Z Only Rate Measurement Y A Only

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About the Modules

Chapter

What This Chapter Contains

Module Description and Features

Read this chapter to learn about types, features, and capabilities of the encoder/counter modules.

The modules install into the POINT I/O terminal base (1734-TB or 1734-TBS) and interface with the Point I/O DeviceNet Pass-through (1734-PDN) or the Point I/O DeviceNet Adapter (1734-ADN).

A module serves as a signal conditioner, function block, and counter between the customer process signals on the terminal base and the POINTBus containing the command information. The main functional blocks are the following.

• Customer digital I/O interface

• Counter ASIC

• Microprocessor

The module accepts feedback from the following.

• Encoders (either single ended or differential)

• Pulse generators

• Mechanical limit switches

• Frequencies up to 1 MHz

A filter is available with the following settings.

• 50 Hz

• 500 Hz

• 5 kHz

• 50 kHz)

Turn the filter off to achieve the fastest counting rate. The input voltage range is 5Vdc (VHSC5) or 15-24V dc (VHSC24). The module returns the count or frequenc y in the form of a 24 bit binary number (0 - 16,777,215) expressed in a 32 bit long word.

Each counter has a user-selectable preset and rollover value associated with it.

The module has 2 outputs that access customer power from the POINTBus to facilitate various output device voltage requirements.

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1-2 About the Modules

The outputs are rated to source 0.5A at 10 to 28.8V dc. The output may be tied to an input. This lets you cascade counters of multiple 1734-VHSC modules. The counter has 4 user- selectable On-Off values (windows) associated with it. Tie either output to any or all of the window signals.

Operating Modes

The modules operate in the modes shown in the table.

Mode Description

Counter Mode Read read incoming single-phase pulses, return a

binary count.

Encoder Mode Read incoming two-phase quadrature pulses, return

a binary count.

Period/Rate Mode Count internal clocks during the On period, return a

frequency. Outputs updated only at the end of the period.

Continuous/Rate Mode Count internal clocks during the On period, return a

frequency. Outputs are updated con tinuous ly during the period.

Rate Measurement Mode Read pulses during the sample period, return a

frequency.

PWM Mode (pulse width modulation)

Generate a pulse width modulated signal.

The operation of the counter and encoder modes is nearly identical. The difference between the two modes is in the type of feedback (single-phase versus two-phase) for the count direction (up or down). In encoder mode, a transition is expected on the B input for counting to proceed in a direction; whereas, in counter mode, the B input may be left at a static level.

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You select all operating modes by writing appropriate configuration data to the module.

Counter Mode

The counter mode reads incoming pulses and returns a binary number (0 - 16,777,215

accepts single-phase inputs. The module determines the Phase B input state, and counts up or down accordingly.

) to the POINTBus. The counter mode only

max

About the Modules 1-3

Channel A input is used as the counting pu lse while channel B is used to determine the direction.

[B = High, Count = Down; B = Low or floating (not connected), Count = Up]

The Channel B input may be tied high or low for unidirectional counting, or toggled for bidirectional counting.

EXAMPLE

Example of Counter Mode

ingle Phase Pulse Generator

Count Up Count Down

Input

ount

123

A Input B Direction Z (Store Count)

(Gate / Reset )

210

Input A Input B Input Z

1734-VHSC

Outputs Updated Continuously

Encoder Modes

The encoder mode reads incoming pulses and returns a binary number (0 - 16,777,215

only accepts two-phase quadrature inputs. The module senses the relationship between the 2 phases, and counts up or down accordingly.

) to the POINTBus. The encoder mode

max

There are two basic encoder types, absolute and incremental. A single-output incremental encoder is called a tachometer encoder. A dual channel incremental encoder with one channel leading the other by 90° is called a quadrature encoder.

A system using a quadrature encoder may include an optional zero pulse, or index, serving as a reference mark for system reset. The principal disadvantage of a system using incremental en coders is that a power interruption causes the loss of position reference, so a system must be reinitialized or returned to a known zero position.

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1-4 About the Modules

Absolute encoders typically have higher speed requirements (200 KHz typical) for motion control applications. An absolute encoder has a unique code associated with each position, so the exact position is always known, even if the system power is turned off.

EXAMPLE

Example of Multiplying Encoder Mode X1, X2 and X4

Input A Input B

Z (Store Count)

Input Z

Quadrature Encoder

(Gate / Reset )

1734-VHSC

Forward Rotation Reverse Rotation

Input

123

210

1 Count

Count

4 Count

135246

1352467 10981211

531420

11 9 710 8 6 5 23401

Outputs Updated Continuously

X1 Multiplying Encoder Mode

Quadrature input signals are used to count on the leading (up direction) or trailing (down direction) edge of A for a bidirectional count, and channel B is used to determine the direction.

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[ B = leads A, Count = Down; B = follows A, Count = Up ]

X2 Multiplying Encoder Mode

Quadrature input signals are used to count on leading and trailing edges of A for a bidirectional count, and channel B is used to determine the direction.

[ B = leads A, Count = Down; B = follows A, Count = Up ]

About the Modules 1-5

A F F

X4 Multiplying Encoder Mode

Quadrature input signals are used to count on leading and trailing edges of A and B for a bidirectional count, and channel B is used to determine the direction.

[ B = leads A, Count = Down; B = follows A, Count = Up ]

Period/Rate Mode

The Period/Rate mode returns an incoming frequency and a total accumulated count to the POINTBus, by gating an internal 5 MHz internal clock with an external signal.

This mode determines the frequency and total number of input pulses by counting the number of internal 5MHz clock pulses over a user-specified number of input signal pulses. At the end of the specified number of pulses, the module returns the frequency (0 - 1 MHz). When the frequency is updated, both outputs are checked against their associated presets.

EXAMPLE

Example of Period/Rate Mode

A ( Not Used ) B ( Not Used ) Z

Encoder / Pulse Generator

Z Input ( Pulse )

5 MHz Internal

Sampling Clock

Accumulated Count

ssumes symmetrical pulse, 50% duty cycle, so Period = Sample Time On X 2 {On & Off} requency = 1 / Period If Count = 20, Scalar = 1, and Clock Period = ( 1 / 5 MHz ) requency = 1 / [ ( 20 / 1 ) X ( 1 / 5 MHz ) X 2 ] = 125 kHz

(Gate / Reset )

10 20

Input A Input B Input Z Scalar

5 MHz Clk

1734-VHSC

Frequency & Outputs Updated Here

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1-6 About the Modules

As the frequency of the incoming pulse train at the Z (Gate/Reset) terminal increases, the number of sampled pulses from the 5MHz clock decreases. Since accuracy is related to the number of pulses received over the sample period, the accuracy decreases with increasing frequencies at the Gate/Reset terminal. Refer to the following Scaling table.

Relationship Between Sampled Pulses and Input Frequency

Input Frequency at Z Gate/Reset Terminal Sample Pulses for 1/2 Cycle of Z Gate/Reset Pulse

2.5 Hz 1 M 5 Hz 500 k 10 Hz 250 k 20 Hz 125 k 50 Hz 50 k 100 Hz 25 k 200 Hz 12.5 500 Hz 5 k 1k Hz 2.5 k 2 Hz 1.25 k 5 kHz 500 10 kHz 250 20 kHz 125 50 kHz 50 100 kHz 25

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Scaling the input frequency through the use of a scalar can lessen the decrease in accuracy. A scalar value of 1 returns an accurate input frequency if incoming input pulses have a 50% duty cycle.

Operation of Scalar

In the Period/Rate mode, the scalar lets the incoming pulse train at the Z Gate/Reset pin be divided by a user-defined number. There is one scalar value for each counter. Acceptable values for the scalar are 1, 2, 4, 8, 16, 32, 64, and 128. The default value for each scalar is 1. Note that a 0 scalar is equivalent to a 1.

The product of the Sample Period times the scalar should be less than

6.71 seconds in order to avoid a zero frequency detect indication.

(5 MHz sample time = 200ns; 16,777,216 counts x 200ns x 2 half cycles of Z = 6.71 seconds)

About the Modules 1-7

Z 5

Continuous/Rate Mode

The Continuous/Rate Mode returns an incoming frequency and a total accumulated count to POINTBus, by gating an inte rnal 5 MHz internal clock with an external signal.

Similar to the Period/Rate mode except outputs in this mode are updated continuously. This mode determines the frequency and total number of input pulses by counting the number of internal 5 MHz clock pulses over a user-specified number of input signal pulses. Each output is turned on as soon as the turn-on count is reached, and turned off as soon as the turn-off count is reached. As the internal 5 MHz clock is counted, the outputs dynamically track the 5 MHz count.

EXAMPLE

Example of Continuous/Rate Mode

A ( Not Used ) B ( Not Used ) Z

ncoder / Pulse Generator

Input ( Pulse ) MHz Internal

ampling Clock

ccumulated Count

Assumes symmetrical pulse, 50% duty cycle, so Period = Sample Time On X 2 {On & Off}

Frequency = 1 / Period If Count = 20, Scalar = 1, and Clock Period = ( 1 / 5 MHz ) Frequency = 1 / [ ( 20 / 1 ) X ( 1 / 5 MHz ) X 2 ] = 125 kHz

(Gate / Reset )

10 20

Input A Input B Input Z Scalar

5 MHz Clk

1734-VHSC

Frequency Updated Here

Outputs Updated Continuously

As the frequency of the incoming pulse train at the Z Gate/Reset terminal increases, the number of sampled pulses from the 5 MHz clock decreases. Since accuracy is related to the number of pulses received over the sample period, the accuracy decreases with increasing frequencies at the Gate/Reset terminal. (Refer to the “Operation of Scalar” information and table in the Period/Rate Mode.)

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1-8 About the Modules

Rate Measurement Mode

The Rate Measurement mode determines the frequency and total number of input pulses over a user-specified sample period. At the end of the interval, the module returns a value representing the sampled number of pulses and a value indicating the incoming frequency.

When you update the count and frequency, you check any associated outputs against their associated presets. Frequency is calculated by dividing the accumulated count by the user-selected time period, and is returned in the read data. Allowable time periods are 10 ms to 3 s in 10 ms increments, with a default value of 1 s. Note that a 0 time period is equivalent to the 1 s default.

EXAMPLE

Example of Rate Measurement Mode

A Input B ( Not Used ) Z ( Not Used )

(Gate / Reset )

Encoder/Pulse Generator

A Input ( Pulse )

Internal Sampling Gate Accumulated Count

User Selectable Sample Period,

10ms to 2s in 10ms increments.

If Sample Period is 50ms, and Count = 3, then Frequency = 3 /50ms = 60Hz

Input A Input B Input Z

Time Base

1734-VHSC

Frequency Calculated, Outputs Updated Here

Pulse Width Modulation (PWM) Mode

The Pulse Width Modulation mode uses the counter to generate a continuous rolling sequence of numbers. The real-time PWM value written to the module is converted to a window edge so that a variable duty-cycle signal can be generated. The counter resets to zero based upon the PWM period programmed into the module. Any output tied to Window 0 transmi t s the PWM signal.

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About the Modules 1-9

New Data Indicator

A two-bit counter, C1 and C0, is updated every time an event occurs, indicating that new data is available in the Stored/Accumulate d Count words. Events are defined as:

Any active gate transition in any of the Store Count (Counter or Encoder) modes

The end of the gate sample period in either the Period / Rate, Continuous / Rate or PWM modes

The end of the programmed sample period in the Rate Measurement mode

To use these bits reliab ly, acquisition of data fro m the counter module must occur faster than the events, which cause C1/C0 to increment. When C1/C0 is updated, a change of state (COS) message can be sent.

Default Configuration

The module default configuration on startup are the following.

• Counter mode

• 50 Hz filter on A, B, and Z

• No time base

• Active Output Assembly = 105

• Rollover = 0x00FFFFFF

• Preset = 0

• No scalar

• Output 0 untied

• Output 1 untied

• Window comparators = 0

• Counter Control Safe State = 0

• Output Control Safe State = 0

To modify the default settings to those required for your application, refer to the appropriate section of this publication.

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1-10 About the Modules

R a

Operating Mode Features

Operating Feature Counter

Preset Y Y N N N N Rollover Y Y N N N N Software Reset Y Y Y Y Y Y Store Count -

Z Gate / Reset 4 modes

Scale Input Count at Z Gate / Reset

Z Gate / Reset Invert Bit Y Y Y Y N N Enable /Force Outputs Y Y Y Y Y Y Assign Outputs Y Y Y Y Y Y Operate Outputs

(Based On) Sample Period N N N N Y Y

See the table for a summary of features active in each mode.

Up / Down

YYNN N N

NNYY N N

Y (Count)

Encoder X1, X2 & X4

Y (Count)

Period /Rate

Y (Count)Y (Count)

Continuous /Rate

Rate Measurement

Y (Count)

PWM

Y (PWM Value)

Operating Mode Features

The Z Gate/Reset Terminal operates in one of fou r modes when the Store Count feature is in use. The four figures below detail the operation in each mode.

Store Count Mode 1: Store/Continue

In mode 1, the rising edge of a pulse input on the Z Gate/Reset terminal causes the current counter value to be read and stored in the Read Data file. The counter continues counting. The stored count is available in the Stored/Accumulated Count word. The stored count information remains until it is overwritten with new data.

Store/Continue

ead, Store Count, nd Continue Counting

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About the Modules 1-11

Store Count Mode 2: Store/Wait/Resume

In mode 2, the rising edge of a pulse input on the Z Gate/Reset terminal reads and stores the current counter value in the Stored/Accumulated Count word and inhibit counting while the Z Gate/Reset terminal is high. Counting resumes on the falling edge of the pulse at the Z Gate/Reset terminal. The stored count information remains until it is overwritten wi th new data.

Store/Wait/Resume

top Counting

tore Count Resume Counti

Store Count Mode 3: Store-Reset/Wait/Start

In mode 3, the rising edge of a pulse input on the Z Gate/Reset terminal stops counting, reads, and stores the current counter value in the Stored/Accumulated Count word, and resets the counter to zero. The counter does not count while the input pu lse on the Z Gate/Reset terminal is high. Counting resumes from zero on the falling edge of the pulse at the Gate/Reset terminal. The stored count information remains until it is overwritten wi th new data.

Store-Reset/Wait/Start

ounter has stopped Counting Stop Count, Store,

and Reset to zero from zero

Start Counti

Store Count Mode 4: Store-Reset/Start

In mode 4, the rising edge of a pulse input on the Z Gate/Reset terminal stores the current counter value in the Stored/Accumulated Count word and reset the counter to zero. The counter continues counting while the Z Gate/Reset terminal is high. The stored count information remains until it is overwritten with new data.

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1-12 About the Modules

O a

Store-Reset/Start

Start Counting

tore Count, nd Reset to zero

Continue Counti

Output Control

To connect an output to a compare window, you could program the module accordingly:

• Tie Output 0 to Window 0

• Program Window 0 ON Value to 2000

• Program Window 0 OFF Value to 5000

ON-OFF Operation of Output 0

Output remains energized for 3000 additional counts

utput turns ON at count value of 2000

If the OFF value is greater than the ON value, the output turns ON at 2000 and OFF at 5000. If the ON value is greater than the OFF value, the output turns OFF at 2000 and ON at 5000.

ffect of ON-OFF Value on Output Operation

Output remains Energized for 3000 additional counts

utput turns ON Output turns OFF

t count of 2000

at count of 5000

Output turns OFF Output turns O at count of 2000

Output turns OFF at count value of 50

Output remains Deenergized for 3000 additional counts

at count of 500

Turn Off Value > Turn On Value

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Turn On Value > Turn Off Value

Install the Module

Chapter

What This Chapter Contains

Read this chapter for information about how to install the modules.

The 1734-VHSC module is a two-module set. Module 1 houses the 1734-VHSC functionality while module 2 provides screw terminals necessary to access chassis gro und (Chas Gnd) and common (C).

Module 2 also connects terminal 4 to 5 and terminal 6 to 7 for ease of wiring power to the input device. Module 2 is not necessary for VHSC functionality but eases customer wiring. Module 2 does not use a node address, and it doesn’t consume power from the POINTBus. To reduce loop area, place module 2 adjacent (either side) to module 1.

For Information About How To See Page

Before You Begin 2-1 Install the Mounting Base Assembly 2-1 Install the Module 2-4 Install the Removable Terminal Block 2-6 Remove a Mounting Base 2-6 Wire the Modules 2-7

Before You Begin

1 Publication 1734-UM003B-E N-P - August 2005

ATTENTION

Preventing Electrostatic Discharge

This equipment is sensitive to electrostatic discharge, which can cause internal damage and affect normal operation. Follow these guidelines when you handle this equipment:

• Touch a grounded object to discharge potential static.

• Wear an approved grounding wriststrap.

• Do not touch connectors or pins on component

boards.

• Do not touch circuit components inside the equipment.

• If available, use a static-safe workstation.

• When not in use, store the equipment in

appropriate static-safe packaging.

+ 51 hidden pages

Rockwell Automation 1734-VHSC24 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Important User Information

Summary of Changes

Summary of Changes

Table of Contents

Preface

Purpose of This Manual

Who Should Use This Manual

Related Products and Documentation

Definitions

About the Modules

What This Chapter Contains

Module Description and Features

Operating Modes

Operating Mode Features

Install the Module

What This Chapter Contains

Before You Begin