Category: A-B

General Diagnostic Features

The thermocouple/mV module contains diagnostic features that can

help you identify the source of problems that may occur during

power-up or during normal channel operation. These power-up and

channel diagnostics are explained in chapter 7. Module Diagnostics

and Troubleshooting.

System Overview

The thermocouple module communicates to the SLC 500 processor

through the parallel backplane interface and receives +5V dc and

+24V dc power from the SLC 500 power supply through the

backplane. No external power supply is required. You may install as

many thermocouple modules in your system as the power supply can support.

Each individual channel on the thermocouple module can receive

input signals from thermocouple sensors or mV analog input devices.

You configure each channel to accept either input. When configured

for thermocouple input types, the thermocouple module converts the

analog input voltages into cold-junction compensated and linearized,

digital temperature readings. The 1746-NT4 uses the National Bureau

of Standards (NBS) Monograph 125 and 161 based on IPTS-68 for

thermocouple linearization.

When configured for millivolt analog inputs, the module converts the

analog values directly into digital values. The module assumes that the

mV input signal is already linear.

Hardware Features

The thermocouple module fits into any single-slot, except the

processor slot (0), in either an SLC 500 modular system or an SLC 500

fixed system expansion chassis (1746-A2). It is a Class 1 module (uses

8 input words and 8 output words). It interfaces to thermocouple

types J, K, T, E, R, S, B, and N, and supports direct ±50 mV and ±100

mV analog input signals.

The module requires the use of Block Transfer in a remote configuration.

The module contains a removable terminal block providing

connection for four thermocouple and/or analog input devices. There

are also two, cold-junction compensation (CJC) sensors used to

compensate for offset voltages introduced into the input signal as a

result of the cold-junction, i.e., where the thermocouple wires connect

to the module wiring terminal. There are no output channels on the

module. Module configuration is done via the user program. There are

no DIP switches.

Module Operation

Each input channel consists of an RTD connection, which provides:

· excitation current

· a sense connection, which detects lead-wire resistance

· a return connection, which reads the RTD or resistance value

Each of these analog inputs are multiplexed to an analog converter.

The A/D converter cycles between reading the RTD or resistance value, the

lead wire resistance, and the excitation current. From these readings, an

accurate temperature or resistance is returned to the user program.

The RTD module is isolated from the chassis backplane and chassis ground.

The isolation is limited to 500V ac. Optocouplers are used to communicate

across the isolation barrier. Channel-to-channel common-mode isolation is

limited to ± 5 volts.

LED Status

The illustration below shows the RTD module LED panel consisting of nine

LEDs. The state of the LEDs (for example, off, on, or flashing) depends on the

operational state of the module (see table on page 1-9).

System Operation

The RTD module has 3 operational states:

· power-up

· module operation

· error (module error and channel error)Power-up

At power-up, the RTD module checks its internal circuits, memory, and basic

functions via hardware and software diagnostics. During this time, the module

status LED remains off, and the channel status LEDs are turned on. If no

faults are found during the power-up diagnostics, the module status LED is

turned on, and the channel status LEDs are turned off.

After power-up checks are complete, the RTD module waits for valid channel

configuration data from your SLC ladder logic program (channel status LEDs

off). After configuration data is written to one or more channel configuration

words and their channel enable bits are set by the user program, the channel

status LEDs go on and the module continuously converts the RTD or

resistance input to a value within the range you selected for the enabled

channels. The module is now operating in its normal state.

Each time a channel is read by the module, that data value is tested by the

module for a fault condition, for example, open-circuit, short-circuit, overrange,

and under range. If such a condition is detected, a unique bit is set in

the channel status word and the channel status LED flashes, indicating a

channel error condition.

The SLC processor reads the converted RTD or resistance data from the

module at the end of the program scan or when commanded by the ladder

program. The processor and RTD module determine that the backplane data

transfer was made without error and the data is used in your ladder program.

Overview

This chapter describes the 8-channel 1746-NR8 RTD/Resistance Input

Module and explains how the SLC controller gathers RTD (Resistance

Temperature Detector) temperature or resistance-initiated analog input from

the module. Included is:

· a general description of the module’s hardware and software features

· an overview of system operation

For the rest of the manual, the 1746-NR8 RTD/Resistance Input Module is

referred to as simply the RTD module.

The RTD module receives and stores digitally converted analog data from

RTDs or other resistance inputs such as potentiometers into its image table for

retrieval by all fixed and modular SLC 500 processors. An RTD consists of a

temperature-sensing element connected by 2. 3. or 4 wires that provide input

to the RTD module. The module supports connections from any combination

of up to eight RTDs of various types (for example: platinum, nickel, copper, or

nickel-iron) or other resistance inputs.

Description

The RTD module supplies a small current to each RTD connected to the

module inputs (up to 8 input channels). The module provides on-board

scaling and converts RTD input to temperature (°C, °F) or reports resistance

input in ohms.

Each input channel is individually configurable for a specific input device.

Broken sensor detection (open- or short-circuit) is provided for each input

channel. In addition, the module provides indication if the input signal is

out-of-range. For more detail on module functionality, refer to the subsection

entitled System Overview later in this chapter.

Description

The RTD module receives and stores digitally converted analog data

from RTD units or other resistance inputs such as potentiometers into

its image table for retrieval by all fixed and modular SLC 500

processors. An RTD module consists of a temperature-sensing element

connected by two, three, or four wires that provide input to the RTD

module. The module supports connections from any combination of

up to four RTD units of various types (for example: platinum, nickel,

copper, or nickel-iron) or other resistance inputs.

The RTD module supplies a small current to each RTD unit connected

to the module inputs (up to 4 input channels). The module provides

on-board scaling and converts RTD unit input to temperature (°C, °F)

or reports resistance input in ohms.

Each input channel is individually configurable for a specific input

device. Broken sensor detection (open- or short-circuit) is provided

for each input channel. In addition, the module provides indication if

the input signal is out-of-range.

Overview

The 1746-N3 Connector Kit is used to terminate a cable which connects field I/O 

devices to SLC 500 32-point I/O modules. The kit contains a keyed 40-pin socket 

header with 45 socket crimp type contacts.

The N3 connector is compatible with 32-point I/O modules, catalog numbers 

1746-IB32, -IV32, -OB32, -OB32E -OV32 and Allen-Bradley 1492-IFM40 terminal 

blocks (see illustration). When the 1746-N3 is used to terminate the I/O cable at the 

1492-IFM40 end, it should be wired in a straight-through manner (i.e. pin 1 to pin 1, 

pin 2 to pin 2, etc.). For additional instructions, refer to the wiring instructions 

provided with your 32-point I/O module.

Use 24 AWG wire with the 1746-N3. Maximum wire length to the user terminal 

block is 10 meters for inputs and 3 meters for outputs with 7-strand, 24 AWG wire.

Assembly Procedure for Crimp Contacts

The following details the assembly procedure for the crimp type contacts.

1. Strip the wire insulation as shown in Figure 1.

2. Insert the wire up to the wire stop as shown in Figure 2.

3. Crimp with DDK crimp tool 357J-5538. Equivalent Amp part numbers are: 

pin – 87666-2, connector – 102387-9, and crimp tool – 90418-1.

If a crimp tool is not available, used the following crimping procedure:

a. Crimp the wire barrel around the wire using a small needle nose pliers.

b. Crimp the insulation barrel around the wire insulation using a small 

needle nose pliers.

c. Solder wire and wire barrel together.

4. After completing above assembly, insert the cable into the socket housing as 

shown in Figures 3 and 4. Check to make sure that the tang, shown as “A” in 

Figure 4, is properly latched by gently pulling on the wire.

What the module does

The module processes and extracts cyclic injection molding data for 

display on your PC, and responds to alarms that you set to monitor 

critical molding parameters. 

When used with the Pro-Set 200 Injection Molding Control System, 

the module helps you:

• achieve a quicker setup time to obtain optimum part quality

• maintain that quality over the production run

The module and associated DARTWin software help you to set up the 

injection molding machine for optimum performance. Then you set 

alarm limits on critical parameters to detect deviations while making 

parts. You can also set a critical mold pressure to transfer the injection 

process each machine cycle. 

The module is designed for use with the SLC 5/03 (or later) processor. 

You program it to interface with the injection molding machine. The 

module has two independent channels to accept analog pressure inputs 

from sensors or from the SLC processor across the backplane. It 

returns alarm signals and processed molding parameters to the SLC 

processor for your application programming and to your PC for 

graphic display. We show the module in a typical Pro-Set 200 system.

Wiring Notes

• Ground cable shields at one end only.

• Isolate signal wiring from power lines and sources of electrical noise.

• Do not exceed 10V dc on any input terminal.

• Outputs +Exc, +T/R, and -T/R must have a minimum load of 1K ohms.

referenced to analog common.

Features and Benefits

Select I/O modules to exactly match your application. 

Combinationmodules allow you to have inputs and outputs in a single slot for efficient use of your chassis space.

Expand the I/O capacity of your fixed controller system. 

Two discrete I/O modules can be added to the fixed controller’s 2-slot expansion

chassis increasing the flexibility of the system.

All relay contacts are Silver Cadmium with Gold overlay. 

Gold plating resists oxidation and tarnishing resulting from non-use.

Silver Cadmium acts as an excellent conductor.

High-density 32-Point DC I/O and fast response DC inputs are available.

These modules allow you to apply the SLC 500 processors in a broader spectrum of control applications.

LEDs indicate the status of each I/O point. 

Assisting you in troubleshooting, LEDs illuminate when the proper signal is received

at an input terminal, or when the processor applies power to an output terminal.

Terminal identification diagrams on each module. 

Terminal identification diagrams are located on each module making terminal

identification easier.

Description

The Allen-Bradley 1746-HSTP1 is a stepper controller module. 

A single-slotted module capable of operating a wide variety of SLC 500 series processors. 

With a differential encoder motion that is programmable for more than 8.000.000 counts of absolute position.

The 1746-HSTP1’s feedback hardware adapts up to 250 kHz of any frequencies. 

It can provide 250 kHz pulse train output for micro-stepping applications. 

It uses loopback diagnostics and differential incremental encoder feedback devices. 

The 1746-HSTP1 provides a differential feedback that interfaces directly to +5 or +15 V encoders. 

The module has a 5″ x 2″ x 6″ (13 cm x 5 cm x 15 cm) estimated dimension and weighs 15 oz (0.43 kg) approximately. 

Programmable modes of operation reduce the need for setting a DIP switch.

The 1746-HSTP1 module has a 200 mA back-plane current at 5 volts and 90 mA at 24 volts. 

It has a 5V DC differential encoder or 12-24V DC single-ended auxiliary inputs. 

It provides a digital output for the translator with a 4 ms module update time. 

The controller module has a 7 – 30 mA at 5V DV pulse train switching. 

This stepper controller module interface directly to encoders with differential feedback with +5 or +15V signal. 

It is also compatible with transistors with differential input translators, single-ended TTL and interface for opto-couplers.

This module does not include DIP switches for setting and configuration.

The module provides quick operational diagnostics through its embedded LED indicators that provide feedback regarding programming errors, 

normal and abnormal operation and a faulted system. 

This module also has built-in loop diagnostics that monitors the pulse train commands provides to the module’s translator.