Structurally the equipment consists of two parts:
- set of removable panels.
Basis-bench contains reusable laboratory work devices (modules): an input device, regulated and unregulated power supplies, a measuring unit, a load bank, and other devices, as well as a working field for removable panels.
Basis-bench can be equipped with different sets of removable panels, which allows the user to configure it for a specific thematic plan of the institution, as well as purchase additional modules and removable panels when changing the list of laboratory experiments.
Removable panels have the standard A4-size. On the front surface of the panel the lab circuitry is depicted. Switching jacks, some electrical components and controls that affect the results of the study can also be arranged there.
Designed as a printed circuit board with jacks for connection to the basis-bench, the lower part of a removable panel is intended for switching all the necessary elements of the bench when performing laboratory work.
As a rule, one panel is used for several labs. The use of removable panels instead of switching circuits by means of long wires connecting the various units and devices provides the opportunity to:
- focus students’ attention on the studied object;
- simplify the teacher’s monitoring of the students’ actions; it is easy to check the circuits, and hence the academic hour is spent not on the circuit validation and troubleshooting but on the study itself;
- extend the list of labs easily in accordance with changing curriculum.
Most of the removable panels are intelligent, so when the bench is switched on, they automatically adjust the measuring system, power supply parameters, maximum and minimum values of the studied devices, etc.
The removable panels have additional protection of the power supply modules, the measuring system, and the load elements used in the basis-bench from erroneous user actions.
The structure of the standard basis-bench includes:
- input unit IU-03 – 1 pc;
- power supply unit PSU-01 – 1 pc;
- measuring unit MU-03 – 1 pc;
- load bank LB-03 – 1 pc;
- pulse-width converter unit PWCU-01 – 1 pc;
- frequency converter unit FCU – 1 pc;
- removable panels unit RPU-01.
Input unit IU-03 accomplishes basis power supply and includes a protection tripping device, zero protection, and short-circuit protection.
Power supply unit PSU-01 is used to control power supply of the bench and its accessories and provides protection against short-circuit. Power supply parameters:
- power 100W;
- Ups 220V, 50Hz;
- Uout1 +5V, 1А stabilized;
- Uout2 +15V, 1А stabilized;
- Uout3 -15V, 1А stabilized;
- Uout4 +24V, 1А stabilized;
- Uout5 +250V, 1А unstabilized.
Measuring unit MU-03 is built on the basis of a digital multi-channel measuring complex and is designed for simultaneous measurement of parameters and studies of several forms of the electrical signals in the frequency band from 0 to 60 kHz with amplitude from 0 to 400 V. Measuring unit parameters:
- sampling frequency – 1 MHz;
- ADC capacity – 12 bit;
- number of galvanically isolated ports – 3 pcs;
- total number of measurement channels – 21 pcs;
- PC-connection interface – USB.
Measuring unit MU-03 transfers data to the PC during the operation. The software included in the complex provides the display, analysis and processing of the obtained data and has the following options:
- to output up to 21 measuring channels on the same coordinate axes with individual vertical tuning of scale parameters for each of them and with common horizontal tuning of scale parameters for all the channels;
- to conduct easy comparison of the measured signals;
- to display actual, instantaneous, and average values of signals;
- to carry out any channel signal frequency measurement;
- to save data array from buffer for further analysis;
- to export oscillograms to graphic formats.
Pulse-width converter unit PWCU-01 is designed for producing controlled DC voltage. It is based on an intelligent power module controlled by a microcontroller, which allows for a variety of protection (overload, power failure, power surge, etc.) The unit has the following modes of operation:
- symmetrical (alternating diagonal actuation)
- asymmetrical (diagonal actuation of one transistor pair).
Frequency converter unit FCU-03 is designed for producing controlled three-phase AC voltage. It is based on an intelligent power module controlled by a microcontroller, which allows for a variety of protection (overload, power failure, power surge, etc.) It provides the independent control of the output frequency and voltage.
Load bank LB-03 contains three-phase uncontrolled active load.
Removable panels unit RPU-01 is designed for the installation of removable panels, their connection to power sources, measuring instruments, load and control devices.