Invaluable as a development tool, two new PHu modules, the 50 and 150, have been added to the Geeplus range.

Operating with supply voltage from 8vDC to 50vDC, this user-friendly interface enables the designer to explore the maximum performance achievable from a wide range of solenoids during product development. The microprocessor-controlled pick and hold modules use intelligent algorithms to control a wide range of devices with simple user control of current and time parameters.

In operation, a graphic display of the excitation current waveform helps the user to optimise excitation conditions for a solenoid device in order to achieve required force and speed with minimum excitation power, and to see the response speed of the device.

Providing the functions of PWM current regulator and oscilloscope through a simple USB connection to a PC, the PHu-ANA kit allows the user to define ‘Pick Current’, ‘Pick Time’, and ‘Hold Current’ parameters for excitation of the device being evaluated.

While setting up parameters, the solenoid can be switched On or Off from the PC. The ‘Start-2s-Stop’ button energises the device for 2s only, providing protection to small devices which can overheat rapidly if energised with excessive current.

The display shows the current vs time for an interval of 1.5 x the chosen ‘Pick’ time and allows the user to visualise the following parameters: electrical rise time of the current, a ‘spike’ representing impact at the end of stroke allowing stroke time to be monitored and the defining of the reduction of current from ‘Pick’ to ‘Hold’ value.

The text data shows the achieved current values, and the duty cycle of the PWM current control in the Pick and Hold conditions. It also provides some limited diagnosis of problems such as inadequate current capacity of the power supply.

When switched on for long periods, the screen also shows the duty cycle of PWM control, and the junction temperature of the power device in real time.

The Phu-50 module can be configured as a bipolar device (able to deliver current in a forward or reverse polarity to a single load device), as a 2-output device able to drive 2 unipolar devices independently, as a single output device with outputs connected in parallel to reduce power loss or to deliver higher continuous current, or as a single output device with second output functionality not used with similar capability to the 2-output operation.

The Phu-150 module is a unipolar device able to deliver current in one direction.