CleaverBrooks ADAC 1000, Operation Manual

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Chapter 2 — System Components
Part No. 750-386 2-3
The PLC holds the program logic and configuration data for the
ADAC controls. The program logic is password-secured at the
factory. The included power supply powers all of the rack modules
as well as the integrated communications bus.
The remaining control components vary according to the type of
system and the options chosen. The base controller embedded I/O
consists of 16 discrete (digital) inputs, 16 digital outputs, 4 analog
inputs, and 2 analog outputs. A right end cap terminator is required
in order to complete the controller communications bus. It attaches
to the right side of the last module in the rack.
Optional modules can be added to the PLC to provide additional
functionality (see below).
Note: The PLC expects each device to be in a specific slot location. The ADAC
1000 will not function unless all devices are properly installed and configured.
Single Tank PLC Layout (also see Chapter 5, Input/Output Lists )
Base System
1. Processor (Slot 0)
2. Slot 1 - Embedded Digital Inputs - 24VDC
3. Slot 1 - Embedded Digital Outputs - 24VDC
4. Slot 2 - Embedded Analog Inputs
5. Slot 2 - Embedded Analog Outputs
Figure 2-1 Single Tank PLC Layout
DISCRETE and ANALOG Signal Types
Discrete inputs/outputs are used for signals taking on only one of two possible
states (on/off, open/ close, etc.). The input state is represented by a bit (0 or 1) in
the control logic. Example:
Pump Running (yes/no)
Analog signals can assume almost infinite values within the fixed analog input/
output current range of 4-20 mA. The ADAC 1000 PLC converts this current value
to a range in engineering units. Example:
Steam Header Pressure (0-150 PSI)