IS420YDIAS1B GE Mark VIe, Discrete Contact I/O Module

Description:

Functional Description:
The IS420YDIAS1B is a Discrete Contact I/O Module engineered and produced by General Electric for the Mark VIeS Series, which is utilized in GE Distributed Control Systems. This Discrete Input (IS420YDIAS1B) I/O pack facilitates the electrical interface between one or two I/O Ethernet networks and a discrete input terminal board. The YDIA comprises a shared processor board and an acquisition board tailored for discrete input functions. The YDIA I/O pack accommodates up to 24 contact inputs and terminal board-specific feedback signals, supporting three distinct voltage levels. System input to the pack is routed through dual RJ-45 Ethernet connectors and a three-pin power input. Discrete signal input is managed via a DC-37 pin connector that directly links with the associated terminal board connector. Visual diagnostics are offered through indicator LEDs.

Features:
The discrete input acquisition board serves as the second stage of signal conditioning and level shifting, interfacing the terminal board inputs with the control logic. The initial signal conditioning occurs on the terminal board.
The discrete input acquisition circuit employs a comparator with a variable threshold. Each input is isolated from the control logic via an opto-coupler and an isolated power supply, although the inputs are not isolated from each other.
Each of the twenty-four inputs features filtering, hysteresis, and a yellow status LED, which illuminates when an input is detected. The LED remains OFF when the input is deactivated.
The input threshold is determined by the contact wetting voltage input terminal. In most applications, this voltage is adjusted to deliver a 50% input threshold. This threshold is clamped at 13% to prevent an indeterminate state if the contact-wetting voltage drops to zero.
If the contact wetting voltage falls below 40% of the nominal voltage, an under-voltage detector alerts the control system. A special test mode is available to force the inputs from the control pack.
Every four seconds, the threshold is pulsed high and then low, and the response of the opto-couplers is monitored. Non-responsive inputs trigger alarms.

Frequently Asked Questions:

1.What is the voltage of IS420YDOAS1B?
Input Isolation: 1500 V
Input filter ac voltage rejection: 125 V dc

2.How does a Discrete Contact I/O Module differ from analog I/O modules in terms of signal handling and application suitability?
Discrete modules manage binary signals (either 0 or 1), while analog modules process continuous signals within a specific range. Discrete I/O is ideal for straightforward on/off control tasks, whereas analog I/O is employed for applications requiring variable and precise control.

Datasheet Link:

IS420YDIAS1B GE Mark VIe, Discrete Contact I/O Module PDF Datasheet