DS3800HMAC1H1F
DS3800HMAC1H1F
DS3800HMAC1H1F
DS3800HMAC1H1F

GE DS3800HMAC1H1F | Triple-Redundant MAU for Mark IV Turbine Communication

  • Model: DS3800HMAC1H1F
  • Alt. P/N: N/A (discontinued; refer to GE Mark IV documentation)
  • Series: Mark IV (Turbine Control Systems)
  • Type: Media Access Unit (MAU)
  • Key Feature: Triple Modular Redundancy (TMR) with dual coaxial connectors
  • Primary Use: Network communication between turbine I/O modules and TCUs
Get a Quote
Manufacturer:

Our extensive catalogue, including , is available now for dispatch to the worldwide.

Description

Key Technical Specifications​
  • Model Number: DS3800HMAC1H1F
  • Manufacturer: General Electric (GE)
  • Series: Mark IV DS3800
  • Protocol Support: 10Base5 (ThickNet), 10Base2 (ThinNet)
  • Ports: 2 coaxial connectors (RG-58/U), 2 right-angled I/O connectors
  • Data Rate: 10 Mbps (legacy Ethernet)
  • Operating Temperature: -30°C to +55°C
  • Isolation: 1500V RMS port-to-port
  • Power Supply: 12V DC ±10%
  • Certifications: CE, UL, ATEX (Zone 2)

  • Weight: 0.5 kg

    DS3800HMAC1H1F

    DS3800HMAC1H1F

Field Application & Problem Solved​
Problem:
In gas turbine control systems, legacy communication networks (10Base5/10Base2) are prone to signal degradation from EMI, cable damage, or connector corrosion. A single point of failure in the MAU can cascade into turbine trips, costing $500k+ per event. For example, a refinery turbine tripped due to a cracked coaxial cable—diagnosed as a “phantom fault” until engineers traced it to water ingress in the connector.
Solution:
The DS3800HMAC1H1F eliminates single-failure risks with TMR architecture. Its dual coaxial ports allow parallel data transmission; if one path fails, the other maintains communication. Field configurable jumpers let technicians adapt to varying cable lengths (up to 500m for 10Base5) without firmware changes.
Core Value:
  • Redundancy: TMR ensures 99.999% uptime in IEC 61508 SIL-2 systems.
  • Diagnostic Clarity: Status LEDs (power, data, fault) reduce troubleshooting time by 70%.
  • Legacy Compatibility: Supports 30+ year-old Mark IV systems without PLC reprogramming.
Installation & Maintenance Pitfalls​
  • Coaxial Cable Stress Relief:
    Mistake: Bending coaxial cables >90° near connectors.
    Result: Signal reflection causes CRC errors.
    Fix: Use 45° bend radius clamps and torque connectors to 8–10 in-lbs.
  • Jumpers vs. DIP Switches:
    Mistake: Assuming all Mark IV MAUs use dip switches.
    Result: Incorrect protocol settings (e.g., 10Base2 vs. 10Base5) lead to “no link” status.
    Fix: Always verify jumper chart in GE 84-01-002 revision 3.
  • Grounding Loops:
    Mistake: Grounding shield at both ends of coaxial runs.
    Result: Creates ground loops, inducing 60Hz noise on data lines.

    Fix: Ground shield only​ at the TCU end.

    DS3800HMAC1H1F

    DS3800HMAC1H1F

Technical Deep Dive​
The DS3800HMAC1H1F operates as a dual-channel network bridge​ within the Mark IV VMEbus framework:
  1. Signal Conversion: Converts I/O module digital signals (TTL/4–20mA) to Manchester-encoded Ethernet frames.
  2. TMR Arbitration: Three identical MAUs run in lockstep; a voting circuit compares outputs, discarding discrepancies.
  3. Diagnostic Engine: Monitors CRC errors, voltage dips (>10% from 12V), and temperature spikes (>70°C).
Failure Modes & Fixes:
  • Cable Break: Replace with shielded RG-58/U (impedance 50Ω ±2%).
  • Jumper Oxidation: Clean contacts with DeoxIT D5 and reseat.
  • VMEbus Collision: Ensure no other modules share the same slot address (0x20–0x3F).

Conclusion​

The DS3800HMAC1H1F is the unsung hero of legacy turbine systems. While newer Mark VI/VIe platforms offer higher bandwidth, this module remains critical for maintaining uptime in brownfield sites. For technicians, mastering its TMR quirks and coaxial discipline is non-negotiable.

Related products