Our rental systems can be combined in series, parallel or matrix configurations with any LAB-GSS modules you have previously purchased, providing they have the same nominal outputs. Up to 64 modules can be connected in this way. This allows any short term requirements outside of usual operating ranges to be met. 

Power Recycling

When sinking energy from the unit under test the LAB-GSS automatically inverts the DC to AC and synchronises this output to the grid. The energy recycled to the grid only has typical losses of around 7%. 

This differs from conventional electronic loads which traditionally waste 100% of electrical energy that could be reused, by simply dissipating it as heat. By using this approach users can save significant electricity costs. Energy waste and thermal issues associated with traditional heat dissipative loads are also eliminated.

Internal Resistance Range

Each module is provided with a user programmable internal resistance range as standard. This makes the power supplies ideal for simulating the ouput of energy storage devices such as battery packs, fuel cell stacks and super capacitors.

Sense Compensation

Sense plus terminals are built into the LAB-GSS for the connection of sense wire which compensates for voltage drops in the load lines. This has a number of advantages over traditional sense. It is permitted to interrupt the load line during operation (voltage on). The maximum voltage drop compensation is adjustable.

The voltage difference between LAB-GSS output and sensing point is monitored. If a set limit is exceeded, the LAB-GSS unit shuts off. This is particularly useful for applications with long cables often prone to unwanted voltage drops.

Versatile Limit Setting (VLS)

The VLS allows the LAB-GSS's output relays to be activated automatically when specific output values are met, protecting the DUT from any damaging charge conditions. Output voltage, current and power values which exceed or fall below a given limit or operating window can be programmed to trigger the relays. Active and inactive areas of operation are defined by a limit value, hysteresis value or a directional designator for the hysteresis.
 

Every module features constant current, constant voltage, constant power as standard. Adjustable internal resistance is also provided.

AC Cables

All rental LAB-GSS systems are provided with AC input cables as standard.

Active Power Factor Correction

LAB-GSS modules have Active Power Factor Correction (PFC) circuit integrated into the input stage as standard. This enhances the overall efficiency of the modules across the output power range when compared to a unit that does not have active PFC. In practice, this means a significant lower peak current value, a decrease of RMS value of the phase current and less perturbations of other equipment running on the same grid.

As standard each module is supplied with isolated analogue and RS-232 interfaces. Other methods of control are possible depending on module availability including: front panel control and display along, CANmp high speed digital interface operating at 1kHz, USB and Ethernet. 

RS-232 Interface

The RS-232 interface is configured as a Sub-D 9 pin connector (female) and is located on the front panel. The graphical user interface, TopControl is operated via RS-232. The software runs on Windows and allows the user to control, measure and configure the power system.

Analogue Interface

The control port is configured as a Sub-D 25 female connector and is located on the rear panel. It allows output values to be set and read proportionally using a 0-10VDC analogue signal. Digital inputs and outputs enable various functions such as the interlock and output ON/OFF. A 10VDC reference is provided for analogue control. Digital functions are switched via a high/low signal. A 24VDC supply voltage is provided for these functions.

All LAB-GSS units come with a simple and intuitive TopControl operating GUI. Live values of the power system are displayed graphically along with any warning and error messages. The software provides a variety of second level parameters, ideal for users who like to optimise their test processes. In standard user mode the operator can remotely program set values, enable voltage output as well as the ability to anlyse different variables including set and actual values via the integrated scope.

The scope function can simultaneously record up to 8 system variables. Recording can be started manually or by a defined trigger event from any variable of the system. All actual and set values (currents/voltages/power/internal resistance) can be recorded. Other recordable items include system temperatures, intermediate DC circuit, low voltage auxiliary power supplies, error related values and variables from the controller section. 

A password protected section is available to the advanced user and service technician. In addition to the standard functions the authorised user is able to:

• Program linear ramp functions at start up and set value steps during operation
• Configure multi-unit operation
• Program the PID controller parameters
• Program the unit's limit values
• Calibrate and adjust values as necessary
• Update the firmware

Function Generator

As well as custom shapes, standard square, sawtooth and sine waveforms can be plotted against time. Voltage/current and voltage/power relationships can also be programmed where necessary. Parametric programming is possible, where 
instead of the time axis, an input variable V_IN, I_IN or P_IN can be selected.

On request, additional application GUIs can be provided with LAB-GSS rental modules, which allow real world behaviour of a power component to be replicated. Please let us know beforehand if you require a specific GUI for your test set-up.

Battery Emulation

BatSim provides a convenient method for the LAB-GSS to emulate different sized battery stacks. Nearly all relevant electrical characteristics are programmable, including the number of cells, energy capacity, cut off limits, chemistry type and nominal voltage.

Electric/Battery Drive Cycling

Drive cycle tests can be implemented using BatControl. Previous data obtained from a test track can be imported and recreated, allowing the LAB-GSS to simulate a real world driving test inside a lab environment. Battery and capacitor charge/discharge profiles can also be implemented through the GUI.

Capacitor Simulation

The bidirectional characteristics of a real capacitor stack can be emulated when CapSim is installed with LAB-GSS modules. Number of cells in series/parallel, state of charge, cell cut off limits, dynamic capacitance and resistance are programmable.

Solar Array Simulation

SASControl software has all EN 50530 tests pre-installed. The GUI allows users to edit irradiance, temperature and amplitude values. Previous tests have been conducted using over 400,000 invividual data points, with more possible.

All modules are shipped in flight cases which make deployment of the power systems simpler, quicker and safer.

A selection of safety features are provided, which vary by flight case. These include a status indicator that alerts users of any residual energy on the DC link that is greater than 15V. This operates even if the mains power is turned off. Another indicator assesses the quality and correct rotation of the AC input voltage and illuminates if correct. 

Panel mounted DC sockets are available which are both mechanically keyed and colour coded to eliminate any possible user errors.

If you are looking to purchase a system, new LAB-GSS modules can be found in our Bidirectional DC range. Unidirectional LAB-TC units are also available in our selection of new DC sources.

The versatile programming capability of the LAB-GSS ensures that it is popular across many research and development sectors. Common applications include battery/capacitor emulation, implementing drive cycles, fuel cell loading, testing flywheels, battery cycling, component lifetime testing, as well as the testing of inverters and DC-DC converters.

The modules are particularly popular in electric vehicle research, with the UK's largest independent automotive EV powertrain testing facility Intertek Transportation Technologies using them within their test cells. A system has also been utilised by Lyra Electronics to develop an airport baggage loader powered by an electric motor.

ISO 16750-2 Testing

65V LAB-GSS modules can perform a number of ISO 16750-2 tests. The embedded function generator allows the modules to implement the voltage/time relationships which many of the strict standards require. Specific Tests which can be performed include:

• 4-5: Slow Decrease and Increase of Supply Voltage 
• 4-6-1: Discontinuities in Supply Voltage
• 4-6-2: Reset Behaviour at Voltage Drop
• 4-6-3: Starting Profile
• 4-6-4: Load Dump
• 4-9-1: Single Line Interruption
• 4-10: Short Circuit Protection

Cranking Curve Testing

Electrical components within a vehicle's subsystem must be able to withstand a wide range of input voltage surges and drops during a start-up. The LAB-GSS can accurately recreate these conditions within a lab environment. This increases reproducibility and accuracy of results when compared to using real batteries.

Hard to replicate conditions such as voltage cranking during a cold start can be achieved. Voltage/current and voltage/power relationships can be programmed against time where necessary.

Voltage Drops and Interrupts

In electronic systems sudden voltage interruptions may cause unexpected behaviour. Supply line disturbances may have several causes, including an additional switch on of large capacitive loads parallel to the supply line or a short circuit caused by loads sharing the supply. The LAB-GSS can generate many complex DC waveforms to test devices under realistic conditions to identify any potential issues.