Interface test units

Test Interfaces

Our standard designs include the R2TES Test Environment Simulator, the Maxitest dedicated portable test unit, the TIU Test Interface Unit and the Solenoid Driver Unit.

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R2TES - TEST ENVIRONMENT SIMULATOR

Standard functions

For each project involving new hardware to be built and tested, a Test Environment Simulator is constructed.  This provides simulated sources of all the signals which are input to the unit under development, and displays the output signals from the unit on lamps or LCDs.  It can provide any or all of the following features:

• pots to provide analogue voltages, with switched preset values for calibration,
• switches for digital input setting,
• power supply switching,
• Emergency Stop latching push-button,
• LEDs of various colours, or incandescent bulbs to display logic levels,
• digital and analogue panel meters to display PWM output values,
• synchronised pulse trains to simulate rotating machines,
• interface for RS232 monitoring port for R2Scope,
• connectors, cables, etc. are chosen to suit best the needs of the development project.

Special Features

In many cases, the Environment Simulator is required to contain special circuitry to meet the need for a more complex test.  For example:

• milli-volt sources for thermocouple simulation,
• closed loop control of simulated engine speed with cranking and load adjustment,
• closed loop control of simulated Variable Geometry Turbocharger,
• interface to J1708 databus,
• simulation of unit injector electrical characteristics,
• MIL-STD-1553B interface with displays and controls,
• screening and fibre-optic interface for EMC testing.

MAXITEST

The Maxitest is a dedicated portable test unit for diagnosing a Main Battle Tank in-line fuel pump or its controller.

The unit is entirely hardware based, generating a PWM drive signal to position the fuel control element.  In its standard positioning mode it sets the control rod to a position set by the operator's control knob, and displays either the sensed signal or the drive requirements.  Other modes enable the user to check speed pickup and the smooth movement of the control rod.

The Maxitest may be used either as a stand-alone test equipment, or in conjunction with an operating controller, for example a MECU or an R2DEC.  In the latter configuration, it is able to provide diagnosis of faults in the controller, by simulating the signals of a working pump.  It can also work in a passive monitoring mode, displaying the signals passing between the controller and the pump.

The task of diagnosing a faulty system is thus made simpler, faster and more conclusive with the aid of this equipment.

Physical Details

The unit is housed in a rugged aluminium case. It is capable of interfacing with the following peripheral equipment:

• an in-line fuel pump - including associated sensors,
• a 24 volt power supply.

TIU - TEST INTERFACE UNIT

The Test Interface Unit, part number CT00051, is a dedicated communications equipment designed for the engine pack of the Crusader programme.  It is designed to be used as a command panel in the test cell environment or for stand-alone (ground hop) testing of the pack.

Facilities are included to simulate all the signals which would normally emanate from the vehicle systems.  This includes analogue voltages, digital signals and a dual-redundant MIL-STD-1553B serial databus.

The controls allow the operator to start and stop the engine, select transmission and fan modes, and monitor all output signals.  A protected panel allows adjustment of the data messages to the engine via the databus.

A row of circular connectors to MIL-STD-38999 interfaces with the standard vehicle harness, making setting-up a simple process and minimising the logistics load.

Physical Details

The unit is housed in a robust aluminium case, attractively finished in blue and with a carrying handle.  It is capable of interfacing with the following peripheral equipment:

• power supply (28 volt nominal),
• test bed control signals,
• engine electronic control module,
• engine interface unit,
• MIL-STD-1553B databus (dual connector),
• PC monitoring station.

SOLENOID DRIVER UNIT

The R2G2 UK Solenoid Driver Unit is a dedicated test driver to operate with a variety of actuation solenoid types.

The unit is built in a heat sinking enclosure and offers the user extensive flexibility in the testing and development of solenoid actuators.  It includes the following useful features:

• 8 digit non-volatile actuation counter for endurance testing,
• output protection up to 5 amps,
• configurable output stage to provide selection of flyback strategy,
• adjustments for Closure Current, Hold Peak Current and Hold Trough Current as well as Closure Period,
• internal pulse generator for trigger signal, with external input alternative,
• monitor connectors for coil current and voltage,
• multi-turn controls for accurate and repeatable calibration.