IS215ISBBH1A ISBB Bypass Module (New Surplus)

Listed here as an ISBB bypass module in new-surplus factory packaging, the IS215ISBBH1A is General Electric's Speedtronic Mark VI splitter communication switch. It is a standalone, ventilated module — not a card that seats in the VME rack — that installs inline on the Mark VI Ethernet I/O network. Functionally it distributes and routes a communication signal, breaking a full-duplex Ethernet drop out into transmit and receive paths so downstream nodes stay fed. Because a factory-sealed spare drops straight into service, this unit is a sensible board to hold for a machine you cannot afford to have waiting on a shipment.

How the bypass/splitter module functions

The Mark VI carries I/O traffic on an Ethernet network (IONet) that ties the UCVx/UCCx controllers and their VCMI interfaces to the distributed I/O packs. On documented ISBB hardware, ports are labeled Full Duplex (P1), Transmit Out (P2) and Receive In (P3), and a single Receiver Active LED reports upstream health. The module passes communication rather than processing it, which is exactly why a factory-fresh spare restores a link quickly once you have proven the fault is the box and not its surroundings.

Before You Replace: Confirm the Fault Is the Module

New surplus is worth reserving for the fault you have actually isolated. Do the diagnosis before you unwrap a spare:

• Start with Receiver Active. Off means an upstream cable problem or a source that is not transmitting — a finding that usually sends you to the cable or the feeding drop, not the module.
• Inspect and reseat cabling. Ethernet leads and the P1/P2/P3 connections fail far more often than the electronics inside a splitter.
• Prove the source. Check that the upstream controller, VCMI and power supply are healthy; a silent source makes any splitter look failed.
• Rule out configuration. IONet addressing, firmware/ToolboxST mismatch and I/O pack faults imitate a hardware failure.
• Bench the suspect against a known-good drop. If a twin splitter works on the same cable, you have your answer.

Keep the sealed spare for the confirmed failure; that discipline is what makes new-surplus stock valuable.

Decoding IS215 + ISBB + H1A

The number reads in blocks: IS215 for the Mark VI assembly family and its GE lineage, ISBB for the splitter/communication-switch function, and H1A for the hardware build and revision. Match the H-number to your installation — H1A, H2A and H3A are separate variants. Our GE Speedtronic Part Number Decoder explains each field, and if you are comparing platform generations, Mark V vs Mark VI: DS200 to IS200 puts the Mark VI in context.

Where it connects — and what connects to it

The ISBB sits in the communication path with the VCMI interface, the UCVx/UCCx controllers and the Mark VI I/O packs. Explore those companions in our GE Mark VI IS200 Boards collection or the broader GE Speedtronic Turbine Control Boards range.

Information to include when you request a quote

• The complete part number and suffix (IS215ISBBH1A) exactly as printed, plus any extended number.
• A clear photo of the label and packaging.
• Turbine model, Mark VI generation, and whether the system is simplex or TMR (<R>/<S>/<T>).
• Quantity, urgency, and ControlST/ToolboxST version if you have it.

Request Your Quote

This IS215ISBBH1A ships as new-surplus in its factory package, backed by a one-year warranty. Send your details and we will reply with a quote within 24 hours. We deliver worldwide DDP and accept purchase orders from qualified organizations. Use Request a Quote and we will confirm availability and fit.

General Information about the Product
Part Number	IS215ISBBH1A Mark VI IS215
Description	IS215ISBBH1A By GE ISBB Bypass Module Mark VI IS215 New Surplus Factory Package
Condition	newSurplusFactoryPackage With 1 Year Warranty.