763x Series Distributed I/O System

TMI LLC I/O Systems Simulated Instrumentation Additional Hardware


763x Distributed I/O System



 TMI has been providing I/O systems for the nuclear simulation industry for 20 years. TMI offers many types of I/O systems as replacements for simulators. TMI has direct replacements for Singer (all versions)/EAI, CPI and RTP I/O systems, CAE and VMIC. TMI’s direct replacement I/O systems reduce the workload when upgrading as well as eliminate the need for cable adapters. Our IO cards connect directly to the original cables.


TMI has become the leader in the U.S.A. within the nuclear simulation market; in fact TMI delivered 4 times as many I/O systems as all other vendors combined. TMI’s reputation has grown worldwide and as such, has been supplying I/O systems to Europe, Asia and Africa. TMI’s products are used predominately in the nuclear simulation industry but are also used in fossil simulation. TMI’s focus is devoted to the simulation industry.


Hardware Description

The 763x I/O system is an Ethernet based distributed I/O system. It has an industry standard TCP/IP protocol. Each Ethernet Controller can handle over 1,500 I/O points. All the chassis are packaged in 6U VME size card cages. Each card cage can have 24 I/O cards (DO/DI/AO/AI). Any combination is acceptable. Connections on the DO/DI/AO/AI cards are through the P2 connector. The P2 is a 96 pin DIN connector using the A, B and C rows.


Ethernet Controller Chassis

At the heart of the I/O system is the 7656-1 Ethernet Controller. This Ethernet based device connects directly to the simulator computer and is responsible for the direct communication and control of all the I/O cards within the chassis. The Ethernet Controller is located in the first slot of every card cage assembly.  A maintenance communication port is provided for running offline diagnostics. The Ethernet Controller can directly drive up to 48 I/O cards (DO/DI/AO/AI). The Chassis contains a snap-shot display which allows the user to view transfers to and from the panel points.


Chassis Controller Chassis

The Chassis Controller Chassis (7657-1) is a satellite chassis of the Ethernet Controller Chassis. This Chassis connects directly to the Ethernet Chassis over a 40 pin bus know as the Chassis Bus. The Chassis Controller is located in the first slot of the card cage assembly.  The Chassis contains a snap-shot display which allows the user to view transfers to and from the panel points.


DO Card with Intelligent Drivers

The 7632-1 DO cards are 64 bits and use intelligent driver chips. The most common DO card uses sink drivers. These provide a ground (low level) to the I/O point, typically used to drive lamps and relays. The drivers sense over current and over temperature and reduce their output current so they do not exceed the components parameters. In other words, when they sense an over tolerance condition they reduce their output current and protect themselves. They can directly drive LED’s without ghosting. TMI offers 3 options for the DO Board, these include high current/voltage sink drivers, or TTL level outputs as either high true or low true states. The high current drivers have a maximum working voltage of 60 volts and .5 amps. The TTL drivers are TTL levels at +/-24ma. All outputs are on the P2 connector. This is a 96 pin DIN style connector.


DO Card with Source Drivers

The 7632-2 DO cards have 64 bits of output. The outputs provide a source voltage rather than a sink current. They are fully protected drivers which sense over current and over temperature conditions and shut down the output to protect themselves. All outputs are on the P2 connector. This is a 96 pin DIN style connector.


DO Card with Isolated Drivers

The 7632-3 DO cards have 64 bits of output. The outputs are electrically isolated from the DO Card through photo isolation components. The outputs are open collector and used to drive devices up to 24 volts DC. They can directly drive LED’s, lamps and relays. The photo isolation ensures complete electrical isolation between the customer equipment and the DO Card. All outputs are on the P2 connector. This is a 96 pin DIN style connector.


DI Card with Protected Inputs

The 7733-1 DI cards are 64 bit DI’s and sense a low level to go to the true state. The inputs are internally pulled up to 15 volts and when driven below 5 volts the input is active. The inputs are protected to +/-36 volts. All inputs are on the P2 connector. This is a 96 pin DIN style connector.


DI Card with Isolated Inputs

The 7633-2 DI cards have 64 bit DI’s that are electrically isolated between the customer equipment and the DI Card. The isolation is done via a photo isolation component. A low current is received from a DI (switch) which turns on the photo sensor and provides an active DI state. The inputs are internally pulled up. All inputs are on the P2 connector. This is a 96 pin DIN style connector.


Analog Output Card (VOLTAGE)

The 7634-1 is a 32 channel voltage AO (analog output). The AO can be set for up to 4 output ranges, (0-5 volts, -5 to 5 volts, 0 to 10 volts and -10 to 10 volts). The AO’s have 16 bit DAC’s and source and sink +/-20ma. All outputs are on the P2 connector. This is a 64/96 pin DIN style connector.


Analog Output Card (CURRENT)

The 7634-3 is a 32 channel current AO (analog output). The AO card supplies a current of 0-21ma per channel. The AO’s use 16 bit DAC’s. All outputs are on the P2 connector. This is a 64/96 pin DIN style connector.


Analog Input Card

The 7635-1 has 16 Analog Inputs. The AI is can read an input voltage from 0-10 volts. Each input is protected up to 70 volts. The AI’s use 16 bit DAC’s. All inputs are on the P2 connector. This is a 64/96 pin DIN style connector.


I/O Power Supply

The 7834-3 is a 600 watt AC/DC power supply chassis. The input voltage is 85 to 264VAC. The input contains an inline circuit breaker, line filter and on/off switch. The power supply is housed in a 3” x 8” x 19” rack mount enclosure. A distribution board and 10 volt power source is mounted on the unit. The 10 volt power source is used as a power supply for the AI’s. Each I/O Power Supply can power two fully loaded chassis.


Hardware Offline tests

TMI I/O systems provide the user with offline tests. These tests allow the hardware personnel to locate problems quickly. A DORT test is self contained in the Ethernet Controller. It does not require a PC to run. This is useful to verify the simulator as a whole or a section of panel. DORT tests consist of Lamp Step, AO Sweep, AO Set, AO Step, DI Test and Synchroscope Test.


Hardware Requirement

The computer system used to drive the I/O must have an Ethernet (10/100/1000) controller connection with TCP/IP that is dedicated to the I/O system.



There are no software drivers required with the TMI Ethernet I/O system. We use a very simple transfer protocol to write and read panel points. All the I/O points are mapped. The software downloads the I/O configuration to the Ethernet controller via a Map Initialize command. Data is written to panel points (DO and AO) with a write command and panel points are read (DI and AI) with a read command. A simple 20 byte header is used for every transfer. Software samples will be provided.  Fully loaded chassis can exceed 50 HZ time frames.



The I/O system comes with a five (5) year warranty.



TMI can provide installation assistance if necessary. The installation includes mounting and cabling all the hardware supplied by TMI.



All TMI customers are self-maintainers; they need the documentation to perform their maintenance. All schematics and technical manuals are provided.


Customer Base

TMI upgrades more nuclear simulators than all other hardware vendors combined. Nuclear simulation is the heart of TMI’s business.  Below is a list of some of TMI I/O users.


Seabrook Station                      Monticello

Vermont Yankee                        Peach Bottom

Nine Mile Point                          Grand Gulf

Fitz Patrick                                ANO

Northeast Utilities                      River Bend

Limerick                                    Vogtle

Hatch                                        Three Mile Island

Farley                                       KSU Sweden

Beaver Valley                            Detroit Edison

Perry                                        DC Cook

Ginna                                        Palisades

Oconee                                     Clinton

Surry                                        North Anna

TXU                                          STP

Indian Point                               Kewaunee

Point Beach                              Taiwan Electric Power Co.

Robinson                                  Korea Electric Power Co.

Waterford                                 LaSalle

Shearon Harris                          Bruce Power Canada

Wolf Creek                                Byron

Cooper                                     Calvert Cliffs

Oyster Creek                             Dresden

Hope Creek                               Salem

Braidwood                                PPL

TVA                                          NRC

Quad Cities                               Laguna Verde

LNPP                                        Mochovce (Slovakia)

Palo Verde                                LNPP (Russia)

Energy Northwest                      South Africa (fossil and nuclear)

VC Summer                              McGuire




763x Series I/O Chassis