Spectrum Controls 1756-CTR8, User Manual

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1-2 Chapter 1: Module Overview
Owner’s Guide 0300199-01 Rev. D
module is configured through RSLogix 5000 software, defining input type,
counter control, and signal filtering.
Table 1-1. Hardware Features
Hardware Function
OK LED Displays communication and fault
status of the module.
Cal LED Displays a fault condition.
Side Label (Nameplate) Provides module information.
Removable Terminal Block Provides electrical connection to input
devices.
Door Label Permits easy terminal identification.
Self-Locking Tabs Secure module in chassis slot.
Terminal Block Switch Locks the RTB to the module.
The module contains diagnostic LEDs that help you identify the source of
problems that may occur during power-up or during normal operation. Power-up
and diagnostics are explained in Chapter 7, Troubleshooting.
The module communicates with the ControlLogix processor and re5
VDC and +24 VDC power from the system power supply through the parallel
backplane interface. You may install as many counter modules in the system as
the power supply can support.
Channels (0 through 7) can receive AC or DC input signals. Input types must be
configured in channel pairs. Each channel reports both count data and rate data in
independent registers. Extended status information is also available for each
channel.
At power-up, the module checks internal circuits, memory, and basic functions.
During this time, the SYS LED remains on. If the module does not find any
faults, it turns off the SYS LED.
After completing power-up checks, the module waits for a connection to an
owner-controller, then valid channel configuration data from your ladder logic
program. After channel configuration data is transferred, and one or more
channels are enabled, the module continuously converts the inputs to floating
point data for use in your ladder program.
Each time the module reads an input channel, the module tests that data for a
fault, i.e., signal mismatch, or out-of-range condition. If it detects an error
condition, the module sets a unique bit in the status tags.
The module’s input circuitry consists of eight, single-ended inputs, routed into an