Detailed Product Description of XYCOM 70244-701 (XVME-244)

I. Product Overview

XYCOM 70244-701 (XVME-244) is a 6U single-slot VME bus isolated digital I/O module launched by XYCOM Company. It is specially designed for industrial environments with strong interference and high reliability requirements, providing 64 channels of optically isolated I/O (32 input + 32 output). It is the core isolation interface board card between VMEbus control systems and on-site switch quantity equipment. 

II. Hardware Architecture and Mechanical Characteristics

Form Specification: Standard 6U single-slot (Single-Wide) VMEbus size, in accordance with IEEE 1014 specification. It can be directly inserted into the back panel of a standard VME chassis, with convenient installation and strong compatibility.

PCB and Structure: Industrial-grade reinforced PCB, with onboard photoelectric isolation array, bus interface, power management, status indication, and protection circuits. The structure is sturdy, resistant to vibration and shock, and suitable for harsh industrial environments.

Connectors: Equipped with high-density D-SUB connectors, facilitating on-site wiring and signal interconnection, and supporting hot swapping and rapid maintenance.

III. I/O Channel Configuration and Isolation Characteristics

The module has a total of 64 photoelectric isolation channels, divided into 32 input and 32 output channels. The channels are grouped for isolation, with extremely strong anti-interference capability.

Input Channels (32 channels):

Divided into 4 groups, each group 8 channels. Channel-to-channel 300 VDC photoelectric isolation, and 1000 VDC isolation with the VME bus side. Completely blocking ground circulation and high-voltage interference.

Input voltage range 10–35 VDC, compatible with 24 VDC industrial standard signals; supports 35 VDC reverse bias protection to prevent wiring errors from damaging the module.

Built-in hardware anti-jitter circuit to eliminate mechanical contact jitter interference, ensuring stable and reliable signals.

Output Channels (32 channels):

Divided into 4 groups, each group 8 channels. Similarly, there is 300 VDC isolation between groups and 1000 VDC isolation with the bus side.

Output type is current source (Sourcing), the supply voltage can be selected as 10–15 VDC or 15–30 VDC, suitable for different load requirements.

The maximum output current per channel is 400 mA, capable of directly driving relays, solenoids, and indicator lights, etc., for industrial loads.

The output terminals integrate transient suppression and reverse voltage protection, effectively absorbing inductive load switching peak voltages, protecting the module and system safety.

IV. Electrical Characteristics and Performance Parameters

Bus Interface: Compatible with VMEbus A16/A24 addressing and D16/D08 data transmission, supporting slave mode and interrupt functions.

Input Characteristics:

Logic 1: ≥ 10 VDC; Logic 0: ≤ 5 VDC.

Typical input current: 10 mA (24 VDC).

Response Time: ≤ 10 µs (switching from off to on), ≤ 120 µs (switching from on to off).

Output Characteristics:

Conduction Voltage Drop: ≤ 0.8 V (relative to supply voltage).

Off-state Leakage Current: ≤ 400 µA.

Switching Time: ≤ 10 µs (conducting), ≤ 120 µs (switching off).

Power Supply: Powered by VME bus + 5 V, low power consumption, no need for additional external power supply.

Operating Temperature: Industrial-grade wide temperature range **‑40 ℃ to + 85 ℃**, suitable for extreme high and low temperature environments.

Electromagnetic Compatibility: Compliant with IEC 61000‑6‑2/4 industrial EMC standards, excellent anti-static, anti-pulse group, and anti-surge capabilities.

V. Core Functions and Software Characteristics

Channel Independent Control: 32 input/32 output channels can be independently read and written via the VME bus, supporting single-channel/byte/word operations, with flexible programming.

Status Indication: Each channel is equipped with an independent LED indicator, displaying the input/output status in real time, facilitating intuitive on-site diagnosis.

Interrupt Support: Input channels can be configured as interrupt-triggered (rising edge/falling edge), supporting interrupt masking and vector configuration, achieving event-driven real-time response.

Power-On Safety: The output is defaulted to off upon power-on to prevent accidental actions, enhancing system safety. Multi-module expansion: Supports cascading of multiple XVME-244 boards within the same VME chassis, expands I/O scale through address mapping, and meets the requirements of large-scale isolated signal processing.

Six. Typical application scenarios

Industrial automation production line: Limit switch, photoelectric sensor, proximity switch signal acquisition, solenoid valve, contactor control output.

Power and energy system: High-voltage switch status monitoring, relay protection signal isolation acquisition, circuit breaker control output.

Petrochemical and process control: On-site explosion-proof area switch quantity signal isolation transmission, valve control, alarm signal output.

Railway and ship control: Vehicle/ship-mounted equipment status monitoring, signal interlock control, I/O isolation in strong interference environments.

Embedded measurement and control platform: High-reliability switch quantity acquisition and control, signal isolation in strong electromagnetic interference environment.

Seven. Product advantages

Super strong isolation: 1000 VDC bus-side isolation + 300 VDC inter-group isolation, completely isolates high and low voltage from ground potential difference, with extremely strong anti-interference ability.

High reliability: Industrial-grade wide temperature, reinforced design, and complete protection mechanism, stable long-term operation, and reduced maintenance costs.

Strong drive capability: Single path 400 mA output, can directly drive industrial loads, without the need for additional drive circuits.

Easy integration: Standard VME bus, high-density connectors, complete status indication, quick integration into existing VME system.

High cost performance: Single-channel isolation cost is low, balancing isolation performance and economy, suitable for large-scale isolated I/O deployment projects.