DS3800HSQD - Low HP Sequence Board

DS3800HSQD - Low HP Sequence Board DS3800HSQD - Low HP Sequence Board

World Of Controls understands the criticality of your requirement and works towards reducing the lead time as much as possible.

DS3800HSQD - Low HP Sequence Board is available in stock which ships the same day.

DS3800HSQD - Low HP Sequence Board comes in UNUSED as well as REBUILT condition.

To avail our best deals for DS3800HSQD - Low HP Sequence Board, contact us and we will get back to you within 24 hours.


Part No: DS3800HSQD
Manufacturer: General Electric
Function: Low HP Sequence Board
Series: Mark IV
Operating temperature: -33 to 56oC
Size: 8.25 cm high x 4.25 cm
Repair: 3-7 Day
Availability: In Stock
Country of Manufacturer: United States (USA)

Functional Description

DS3800HSQD is a Low HP Sequence Board developed by GE. It is a part of Mark IV control system. It is designed for easy installation and comes with connectors and components for optimal functionality. The board includes mounting holes in each corner for securing it with screws to the drive. The board is equipped with two 40-pin connectors and one 20-pin connector, each with retention levers, to secure ribbon cables in place. On the board's surface, you'll find a 50-pin connector and another 20-pin connector. The board features 1 erasable programmable read-only memory (EPROM) module. It also includes 1 amber indicator LED and 8 red indicator LEDs for status monitoring.

Installing the Ribbon Cable

  • When connecting a 50-wire ribbon cable to the 50-pin connector, follow these steps:
  • Ensure proper cable routing to facilitate heat dissipation from board components.
  • Fold the cable and route it across the board, along the interior side of the drive, avoiding interference with airflow.
  • Handle the cable with care, as the 50 control signal wires are delicate and easily detached from the plastic connector:
  • Firmly hold the connector with one hand.
  • Gently remove it without tugging on the ribbon cable to prevent damage.

Upgrading to a Newer Board Version

  • If replacing the GE Low HP Sequence Board, the newer version may offer improvements in performance and component design.
  • Changes in the circuit layout may necessitate component repositioning.

Amber Indicator LED Status

  • A lit amber indicator LED indicates the board has received power and successfully completed startup diagnostics.
  • If the amber LED is not lit, it suggests a lack of power and unsuccessful startup diagnostics. In such cases, check the board's power source and attempt a restart for normal operations.


  • Speed and Position Sensors: Includes sensors that measure the rotational speed and position of the turbine shaft. These sensors may be based on different technologies, such as magnetic or optical encoders, and are designed to provide accurate and reliable speed and position measurements.
  • Signal Conditioning and Amplification Circuits: The signals from the sensors are typically weak and require amplification and conditioning before they can be processed by the control system. The SPI board includes circuits that perform this function, ensuring that the signals are of sufficient strength and quality to be used by the control system.
  • Redundant Sensors: To ensure high reliability, the board often includes redundant sensors. This means that there are multiple sensors measuring the speed and position of the turbine shaft, and the signals from these sensors are compared to ensure that they are consistent. If there is a discrepancy between the signals, the control system can use a voting algorithm to determine the correct value.
  • Fault-Tolerant Circuits: Designed with fault-tolerant circuits that can detect and respond to errors or malfunctions in the system. For example, if one of the sensors fails, the control system can automatically switch to a backup sensor, ensuring that the speed and position measurements remain accurate and reliable.
  • Diagnostic Features: Include diagnostic features that allow the control system to monitor the health of the board and detect any faults or malfunctions. This can include built-in self-tests or diagnostic algorithms that analyze the sensor signals and alert the control system if there are any issues.

WOC is happy to assist you with any of your GE requirements. Please contact us by phone or email for pricing and availability on any parts and repairs.


What is DS3800HSQD?
It is a Low HP Sequence Board developed by GE

How should I handle the 50-wire ribbon cable when connecting it to the 50-pin connector?
Ensure proper cable routing for heat dissipation from board components. Neatly fold the cable and route it across the board and along the interior side of the drive to avoid blocking airflow.

What precautions should I take when disconnecting the 50-wire ribbon cable?
Handle the cable delicately, as the 50 control signal wires are fragile. Avoid putting stress on the ribbon cable to prevent wire separation from the connector. Hold the connector firmly with one hand while gently removing it to avoid cable damage.

What does the amber indicator LED on the board signify?
The amber LED lights up when the board receives electrical power and successfully completes startup diagnostic tests. If it's not lit, it indicates a lack of power or unsuccessful startup diagnostics. In this case, check the power source and consider restarting the board.