QL Series - Source-Sink
Features of performance
- Voltage up to 100 V
- Currents up to 320 A
- 2-quadrant or 4-quadrant design
- DC source-sink
- Additional AC source for 4-quadrant models
- User interface with 4.3" touch screen
- Basic operating modes CC, CV, CP, CR
- Combined operating modes CC+CV, CV+CC
- Adjustable upper and lower limits for V and I
- Adjustable internal resistance in CC and CV modes
- Functions for testing energy storage devices
- Internal resistance measurement
- List function with synchronous data acquisition
- Rectangular, PWM and modulation function
- Trigger model
- SCPI programming with measurement functions
- RS-232, USB, LAN, CAN, I/O port standard
- GPIB optional
- Isolated I/O port optional
- Analog monitoring outputs for voltage and current
- Analog control inputs for control V/I and limit V/I
- Save settings
- Electronic protection
- Bilingual help system (DE, EN)
- 2 free calibrations (with registration)
DescriptionQL series devices are sources and sinks or power supply and electronic load in one device. They are used for testing a wide variety of energy storage devices, as well as other DUTs such as motors, chargers or coils.
Basic Operating ModesThe devices have constant current (CC), constant voltage (CV), constant resistance (CR) and constant power (CP) operating modes.
Combined Operating ModesIn CV mode, two current limits (source and sink current) can be set independently. In CC mode, an upper and a lower limit voltage can be set. This provides the combined operating modes CC+CV and CV+CC.
AC Source4-quadrant devices are also capable of the AC source operating mode.
Source-Sink ModeDepending on the output variable setting and the characteristics of the connected DUT, the instrument automatically decides whether to operate as a source or a sink.
2- or 4-Quadrant ModelsInstruments for 2-quadrant operation can supply or sink current when the output voltage is positive. To ensure that the desired function is provided at settings close to 0 V and with longer leads, 2-quadrant devices operate at negative voltages starting at -1 V. So in principle, 2-quadrant devices are also 4-quadrant devices, but with limited negative voltage. 4-quadrant devices can also be used as AC sources.
Energy Storage Test: Charge and Discharge FunctionCharge and discharge functions are used to test energy storage devices by charging or discharging the device under test in CC, CP or CR mode. Both functions can be combined with the list function so that defined charge/discharge profiles are possible. IUa charge or discharge (CC+CV discharge) is also possible: in this case, the DUT is charged or discharged with constant current up to a defined voltage. This voltage is then kept constant until a defined minimum current is reached. Stop criteria for charging and discharging are charge, energy, time, current, voltage. If data is logged as well, a follow-up time can be defined to observe the recovery phase.
Internal Resistance MeasurementIn sink mode, the device can measure the DC internal resistance of the connected source. For this purpose, it uses a calculation method specified in various standards, e.g. DIN EN 61951, DIN EN 61960.
Adjustable Internal ResistanceIn order to simulate different sources as flexibly as possible, a variable internal resistance can be set in constant voltage mode CV. Similarly, a conductance can be set in constant current mode CC.
List FunctionDynamic processes (LIST function) can be simulated with up to 300 set values. The setpoint lists may contain positive and negative values across quadrants, so that there are, for example, charging and discharging currents in one list. The device stores the synchronously acquired measurement values with time stamp.
Rectangular FunctionThe rectangular function provides a convenient way to generate a square waveform by entering absolute times and current or voltage values.
PWM FunctionWith the PWM function, the frequency and the duty cycle can be set in manual mode for the two current or voltage values.
ModulatorIn CC- or CV- mode the modulator adds a sinusoidal, rectangular, triangular or arbitrary signal to a constant setpoint. Frequency and modulation depth are adjustable.
AC Source4-quadrant devices can be used as DC source-sink in the basic modes CC, CV, CP and CR and additionally as AC source in the modes CC and CV. Selectable waveforms are sine, triangle, square, sawtooth or an arbitrary waveform, with adjustable offset. For measurements without oscillations, the waveform can be synchronized in frequency and phase with the mains voltage.
Measurement Data AcquisitionAutomatic data acquisition allows measurement data to be stored internally or directly to an external USB flash drive.
Trigger ModelVarious functions or settings can be triggered by a configurable trigger event:
- Switch source output on/off
- Set triggered operating mode
- Start/stop list operation
- Start/stop data acquisition
- Set triggered settings of all operating modes
Control Speed SelectionFor certain DUTs or very long cables, it may be necessary to adjust the regulation time constant of the source-sink to avoid oscillation and to achieve stable operation. The control speed can be selected from slow - fast.
Watchdog FunctionWhen the watchdog function is activated, the output is switched off in the event of faulty communication with the control PC in order to protect the connected DUT.
Saving SettingsIn order to be able to quickly reconstruct recurring test tasks, the active settings can be stored in non-volatile memory (internally or on USB flash drive) so that they can be reloaded at a later time. 9 internal memory positions are available. The unit can selectively set reset values at power-up, the last active settings at power-down, or memory positions 1 to 9.
Data InterfacesThe following data interfaces are fitted as standard:
- GPIB Interface (option QL02)
I/O PortThe standard I/O port provides analog and digital signals for external control. Inputs:
- Analog setting of I and V with -5 ... 0 ... 5 V or with -10 ... 0 ... 10 V
- Analog upper and lower limit value setting of I or V with -10 ... 0 ... 10 V
- Output switching
- Selection of operating mode CC/CV
- Control speed selection
- Remote shut-down
- Readable digital input
- Trigger input
- Analog voltage monitoring output -10 ... 0 ... 10 V
- Analog current monitoring output -10 ... 0 ... 10 V
- Output activation status
- Status output for upper limit value
- Status output for lower limit value
- Trigger output