SLC 100 Selection Guide
Overview: SLC 100 Controllers
The Allen-Bradley SLC 100 series (Bulletin 1745) is a family of Rockwell Automation microprocessor-based Programmable Logic Controllers (PLCs). These PLCs feature the following functional capabilities: relay control logic, counters, timers, shift registers, and sequencers.
The SLC 100 programmable controllers are easy to program (using basic Ladder Diagram PLC programming language), operate, and maintain, allowing users to fully leverage their technologically advanced capabilities quickly. The SLC 100 controllers are designed more simply, but they also feature the inherent flexibility and high-performance characteristics of other Allen-Bradley programmable controllers.
Here are the key technical specifications of the SLC 100:
- Input voltage range: 170-265 Volts AC, 18-30 Volts DC
- Ten standard input terminals
- Six standard output terminals
- Expandable I/O capability, up to a maximum of 112 Input/Output points
- CMOS RAM (non-volatile RAM) that includes a battery for backup power
- Optional EEPROM (a type of non-volatile ROM) memory module
- Screw mounting or Din-rail mounting
The SLC 100 programmable controllers find use in numerous industrial applications, including:
- Assembly and production lines
- Control of machine tools
- Molding and casting machines
- Material Handling
Selection Guidelines
Selecting the right SLC 100 programmable controller generally depends on your application’s requirements, which determine the memory capacity, I/O capability, additional functionalities, communication options, programming instructions, and accessories required of the SLC 100 controller to be selected.
As such, when selecting a SLC 100 programmable controller for a particular application, ensure that you review the following:
Type of SLC 100 Processor Unit
A typical SLC 100 processor unit contains a Central Processing Unit (CPU), power supply, 10 Input and 6 Output circuits, and battery-backed CMOS Random Access Memory.
SLC 100 processor units are available in four versions to meet various application requirements. The four versions are:
1. 1745-LPI01
The 1745-LP101 processor unit includes ten input terminals, six output terminals, a battery-backed CMOS Random Access Memory, and a built-in Auto/Manual control switch. The switch controls the restarting of the 1745-LP101 processor after a CPU fault correction, power failure, or a brown-out condition. The processor also includes a dedicated port connecting SLC 100 I/O expansion modules to increase its I/O capability.
The rated input voltage for this SLC 100 processor is 85-132V AC at a line frequency of 50 or 60 Hertz. It is available with an electrical disconnect that protects its components from power surges. However, some applications may also require the use of an isolation transformer. In addition, the 1745-LP101 processor is designed to function reliably at an ambient temperature of 0-60 degrees Celsius (32-140 degrees Fahrenheit, and the selected enclosure ought to be sufficient for the environmental conditions of the given application.
2. 1745-LP102
The 1745-LP102 processor unit features battery-backed CMOS RAM – as the processor memory, six output terminals, and ten input terminals. Its rated input voltage range is 170-265 Volts AC. This processor also includes an Auto/Manual control switch, communication port, expansion unit connection port, a built-in electrical disconnect, and all the features illustrated in the diagram above. It can operate reliably at ambient temperatures of 0-60 degrees Celsius (32-140 degrees Fahrenheit).
3. 1745-LP103
The 1745-LP103 processor module consists of ten input terminals, six output terminals, battery-backed CMOS RAM, an in-built Auto/Manual control switch, a communication port, an electrical disconnect, diagnostic LED indicators, an expansion unit connection port, a battery compartment, I/O status indicators, and an EEPROM module compartment. It features a rating of 10-30 Volts for input voltage.
In addition, the maximum leakage voltage for the 1745-LP103 processor in an off-state is 5 Volts, while its maximum leakage current in an off-state is 2 mA (milliamps) for input one and input 2. The recommended operating temperature for this processor is 0-60 degrees Celsius (32-140 degrees Fahrenheit) and requires a NEMA-approved enclosure.
4. 1745-LP104
The 1745-LP104 processor unit includes ten input terminals, six output terminals, battery-backed CMOS RAM as the processor memory, and all the other features of a typical SLC 100 processor unit. This processor can also support up to 112 additional inputs and outputs through SLC 100 I/O expansion modules.
The rated input voltage of the 1745-LP104 processor is 10-30 Volts. While inputs 1 and 2 feature an off-state leakage current rating of 2 mA (maximum).
Available Memory Options
The SLC 100 programmable controllers have a battery-backed CMOS Random Access Memory – a non-volatile RAM that stores system time and date, hardware settings, and other important controller configurations. The CMOS RAM is the processor memory, providing a maximum of 885 words – the standard user memory size provided by SLC 100 processors.
A replaceable lithium battery, accessible from the front end of every SLC 100 processor module, provides backup power for the CMOS Random Access Memory. The CMOS battery has an estimated lifespan of two to three years, after which it should be replaced.
In addition, if your application requires additional memory capacity than that provided by the processor memory, you can include an optional EEPROM (Electrically Erasable Programmable Read-Only Memory) Module – Catalog No. 1745-M1. This memory module can be plugged directly into the SLC 100 processor unit for loading and storage of PLC programs, i.e., using a PC software or a pocket programmer, you can store the processor’s RAM program into the EEPROM module or load a Ladder Diagram program from the EEPROM module into the processor’s RAM.
Note: Installing the 1745-M1 EEPROM module provides maximum protection against loss or alteration of the user-defined SLC 100 programs due to depletion of the backup battery, excessive electrical noise, or processor malfunction.
Standard I/O Capabilities
The SLC 100 programmable controllers are available with the following input and output terminals as a standard:
Ten Input Terminals:
The ten input wiring terminals include self-lifting pressure-type cover plates that allow for secure connections and easy wire insertion. The cover plates are color-coded to identify the voltage level of the input circuits: 24V DC (blue), 230V AC (black), and 115V AC (red).
The input circuitry of the SLC 100 controllers is currently sinking; thus, it is compatible with current sourcing field input devices like PNP transistors. The circuitry also includes optical isolation, surge suppressors, and EMC filters to protect the controller components against damage caused by transient voltages from field input devices.
In addition, SLC 100 processor units include ten red input LEDs that show the status of the connected inputs and are identified with address numbers 1-10 that correspond to the wiring terminals of the connected field input devices. For example, when a given SLC 100 input circuit is activated, the corresponding input status indicator will light up red.
Six Output Terminals:
All SLC 100 processor units include six output wiring terminals for relay contact output circuits. The output relay contacts are isolated from one another, meaning you can wire every output circuit independently. As such, you can also apply a distinct control voltage in each one of the output circuits, as per the requirements of your application. The six output wiring terminals include cover plates that are color-coded to identify the voltage level of every output circuit.
Additionally, all SLC 100 processor units include six output LEDs that indicate the status of the connected outputs. These output status LEDs are identified with numbers 11-16, which correspond to the wiring terminals of the connected output relay contacts. For example, if a programmed SLC 100 output instruction is executed as TRUE, the related output status LED will light up red, while the correlated output relay contact will close.
Internally connected output relay contacts include parallel Resistor-Capacitor (RC) networks that protect the contacts against probable damage by voltage transients from field output devices.
Available I/O Expansion Modules
The SLC 100 controllers support three types of I/O expansion units, namely:
- Basic I/O Expansion Module: This I/O unit comprises ten inputs and six inputs.
- Relay Output Expansion Module: This module does not feature any input circuits; instead, it only consists of 12 relay output circuits powered by a 170-265V AC supply voltage.
- Analog Input Expansion Module: It features analog input circuits only, no output circuitry.
You can interconnect the three I/O expansion modules with SLC 100 processor units to extend the number and type of their I/O circuits up to a maximum of 112 input and output circuits. You can also increase the I/O capability of the selected SLC 100 processor unit by connecting SLC 150 I/O expansion units.
Here are the available SLC 100 I/O expansion modules:
a) 1745-E102: This I/O expansion unit consists of 10 input and six output terminals. It’s powered by a line voltage of 170- 265 VAC, at 50 or 60 Hertz. A 1745-C2 interconnect cable – 18.5 inches, 10-pin to 10-pin ribbon cable – is required to connect the 1745-E102 I/O expansion module with an SLC 100 processor unit.
b) 1745-E101: This I/O expansion module requires an input AC voltage ranging from 85-132V AC at a supply line frequency of 50 or 60 Hertz. It features ten 115V AC discrete inputs and six Normally Open (NO) relay contact outputs operated at 10-250V AC, 50/60 Hertz line frequency, or 10-125V DC. You will require a 1745-C2 communication cable to connect the 1745-E101 expansion module to the SLC 100 processor units.
c) 1745-E103: The module features ten digital input terminals and six output terminals. Its rated supply voltage is 10-30 Volts. The 1745-E103 I/O expansion module is connected to an SLC 100 processor unit through a 1745-C2 ribbon cable.
d) 1745-E104: This I/O expansion unit supports ten discrete inputs and six outputs. It requires a supply voltage of 10-30 Volts. A 1745-C2 cable is required to connect this module to SLC 100 processor units.
e) 1745-E106: The module features eight analog input terminals and no outputs. Its rated input voltage is 0-10 VDC. A 1745-C2 interconnect cable is also required with this expansion unit.
f) 1745-E107: This expansion unit offers eight analog input terminals and no output terminals. Its rated input voltage is 0-10 VDC. To connect the module to an SLC 100 processor, you will require a 1745-C2 ribbon cable.
g) 1745-E105: This relay output expansion module features 12 output terminals (for relay output circuits) and 0 input terminals. It is connected to an SLC 100 processor unit using the 1745-C2 10-pin interconnect cable.
Required Programming Devices
Ensure that the SLC 100 programmable controller you intend to select includes compatible peripheral devices for communication and programming purposes. Essentially, all SLC 100 processor units include a communication port for plugging the following devices:
a) 1745-PT1 Pocket Programmer: This is a handled programming terminal that can be connected to a SLC 100 processor unit via a 1747-C10 communication to program, edit, monitor, and troubleshoot the user-defined SLC 100 program. You can select up to nine operating modes with the 1745-PT1 programmer. The nine modes are:
- Clear Memory
- Program
- Run
- Test-Single Scan
- Test-Continuous Scan
- Store Program in EEPROM module
- Load Program from EEPROM module
- Enter/Change Access Code
- Diagnostic Test-Programmer
In addition, the 1745-PT1 programmer module is available with an LED display that features 7-Segment readouts. It also includes a keyboard with thirty momentary push keys and tactile feedback. A 1747-NP1 or a 1747-NP2 power supply can power this programmer module. Its operating ambient temperature varies from 0-50 degrees Celsius (32-122 degrees Fahrenheit, and it ought to be stored at an ambient temperature of -40-85 degrees Celsius (-40-185 degrees Fahrenheit).
b) 1745-PCC Interface Converter: This SLC 100 personal computer interface allows communication between a SLC 100 programmable controller and a personal computer. It converts RS-422 signals from a SLC 100 processor to RS-232-C signals, which are compatible with IBM or IBM-compatible personal computers.
This RS-232-C/RS-422 interface converter connects to the PC’s 25-pin RS-232 serial port and an SLC 100 processor through a 6-feet serial communication cable. If your computer has 9-pin RS-232 serial ports, you will require a 25-pin to 9-pin serial adapter cable to use the 1745-PCC interface converter.
c) 1745-TCAT: This Timer Counter Access Terminal (TCAT) module allows online monitoring of programmed counter, sequencer, and timer data values. It is connected to an SLC 100 processor unit by a six ft. (1.8m) TCAT interconnect cable. Plug-in connectors can also mate the TCAT module and SLC 100 processor unit.
The 1745-TCAT terminal includes a digital LED display with 7-segment readouts, a keyboard with 16 push keys, and a two-position keylock switch with a cover. The terminal provides two modes of operation: MODIFY and MONITOR. Additionally, its recommended operating temperature is 0-60 degrees Celsius (32-140 degrees Fahrenheit).
Mounting Options
Choose the most appropriate mounting option to install your selected SLC 100 programmable controller. There are two recommended mounting options for SLC 100 controllers, namely: a) DIN Rail Mounting: This option requires mounting an SLC 100 processor module in a NEMA-approved enclosure on an IEC 35 mm x 7.5 mm steel-made DIN mounting rail (Catalog Number 199-1DR). All SLC 100 processor units are available with two DIN rail fasteners.
The DIN mounting rail can be welded, screwed, or bolted to the back panel of the SLC 100 enclosure. The SLC 100 processor module is installed by hanging it on the topmost edge of the mounting DIN rail and pressing it towards the DIN rail until it snaps into place. To uninstall the SLC 100 processor module, loosen the two fasteners of the DIN rail.
b) Screw Mounting: A SLC 100 processor module can be mounted directly to the enclosure’s back panel using four ##10 screws.
