Input and output peripheral controller cards for use in a programmable logic controller system
First Claim
1. In a programmable logic controller system including a processor for coupling to peripheral controller cards through a data bus and a control bus, wherein said peripheral controller cards include an input card for receiving inputs from external apparatus utilizing a line voltage having a peak value and having a voltage range between approximately 12 and 240 volts, AC or DC, said input card for generating logic level signals for use by said processor, the improvement wherein said input card comprises:
- means for generating a reference voltage from said line voltage, said reference voltage being a percentage of the peak value of said line voltage;
means for comparing each of said inputs with said reference voltage and generating a logic true when a corresponding one of said inputs is greater than said reference voltage and a logic false when said corresponding one of said inputs is less than or equal to said reference voltage;
means for scaling said reference voltage and said inputs to logic level voltages.
4 Assignments
0 Petitions
Accused Products
Abstract
The present invention is directed to a programmable logical controller (PLC) system incorporating a universal input controller card, a universal output controller card, and a symmetrical current mirror fuse blown detector circuit. The universal input controller card is capable of tracking input voltages from 12 to 240 volts, AC or DC. The universal output controller card is capable of outputting output voltages ranging from 12 to 120 volts, AC or DC with no significant leakage current and no load resistors. The current mirror fuse blown detector circuit detects blown fuses in each output channel of the output controller card.
37 Citations
19 Claims
-
1. In a programmable logic controller system including a processor for coupling to peripheral controller cards through a data bus and a control bus, wherein said peripheral controller cards include an input card for receiving inputs from external apparatus utilizing a line voltage having a peak value and having a voltage range between approximately 12 and 240 volts, AC or DC, said input card for generating logic level signals for use by said processor, the improvement wherein said input card comprises:
-
means for generating a reference voltage from said line voltage, said reference voltage being a percentage of the peak value of said line voltage; means for comparing each of said inputs with said reference voltage and generating a logic true when a corresponding one of said inputs is greater than said reference voltage and a logic false when said corresponding one of said inputs is less than or equal to said reference voltage; means for scaling said reference voltage and said inputs to logic level voltages. - View Dependent Claims (2, 3, 4, 5)
-
- 6. In a programmable logic controller system including a processor for coupling to peripheral controller cards through a data bus and a control bus, wherein said peripheral controller cards include an output card for supplying outputs to external apparatus utilizing a line voltage, said outputs being controlled by logic level signals from said processor, the improvement wherein said output card comprises switching circuit means for switching said line voltage on and off based upon said logic level signals wherein said switching circuit means operates over a voltage range of at least 12 to 120 volts, AC or DC.
Specification