Delivery and installation of a vibrating sample magnetometer (VSM) for the needs of contract KP-06-N97/5, NIS at TU-Sofia

The order includes the delivery and installation of 1 vibrating sample magnetometer (VSM) for the needs of contract KP-06-N97/5, NIS at TU-Sofia. MINIMUM REQUIREMENTS AND TECHNICAL INDICATORS: 1. FUNCTIONAL REQUIREMENTS AND OPERATING MODES • 1.1. Scope of magnetic research o Automatic measurement and recording of basic magnetic properties of magnetic materials: magnetic hysteresis, magnetization curves, demagnetization, as well as temperature dependencies (heating/cooling curves and temperature change over time), magnetic saturation and remanence, coercivity, maximum magnetic energy, Curie temperature, and magnetic conductivity. • 1.2. Compatibility with various sample forms o The construction must allow for precise measurement of magnetic materials in the form of powders, fine particles, thin films, liquids, and bulk (solid) bodies. • 1.3. Computer control o The system must support a fully automated measurement mode, controlled by a computer. o The software must ensure automatic locking and zeroing of system phases immediately after activating online mode. • 1.4. Autonomous manual mode o Ability to switch to a fully manual mode, where computer control is deactivated. o Modulation to zero, phase shift, time constant, and sensitivity must be controlled directly from the control panel buttons. 2. METROLOGICAL AND TECHNICAL CHARACTERISTICS • 2.1. Magnetic moment range o Measurement range of magnetic moment from a minimum of 10⁻² emu to a maximum of not less than 300 emu (at a pole gap up to 35 mm). • 2.2. Measurement sensitivity o Minimum technical sensitivity in magnetic moment measurement: 5 × 10⁻⁵ emu or better (lower numerical value). • 2.3. Accuracy and repeatability of measurements o Relative accuracy of measurements: better than ±1% (lower numerical value) (at a reference value of 30 emu). o Repeatability of results in successive tests: better than ±1% (lower numerical value is better) (at a reference value of 30 emu). • 2.4. Time stability o System stability during continuous operation within 24 hours: better than ±1% (lower numerical value). 3. ELECTROMAGNETIC SYSTEM AND POWER SUPPLY • 3.1. Electromagnet and field induction o Field source – electromagnet with adjustable induction at the center from a minimum of 0 T to a maximum of not less than 1.3 T (at a fixed air gap between poles of 20 mm). o Diameter of the pole face: minimum 60 mm. • 3.2. Electromagnet cooling o Electromagnet design ensuring operation via natural air cooling system or an equivalent/more efficient technological solution. • 3.3. Power supply stability o DC power supply unit with automatic conversion and a power range from 2 to 30kW o Output current stability: better than 5 × 10⁻⁴ A. • 3.4. Built-in power supply protections o Presence of built-in automatic protection against phase loss/failure, overcurrent protection, and automatic short-circuit protection. • 3.5. Continuous operation time under load o The system must guarantee continuous operation under full load for at least 8 hours (at an ambient temperature of 20±5ºC). 4. VIBRATION MODULE • 4.1. Vibration source characteristics o Vibration source with a fixed operating frequency of 185 Hz and frequency stability better than 10⁻⁵ Hz. o Maximum output power of the vibration module: not less than 50W. The contract enters into force from the date of its registration in the registry of the Contracting Authority. The maximum delivery and installation period is up to 180 calendar days from the date of registration of the contract in the registry of the Contracting Authority. Warranty period for the equipment - at least 12 months from the date of signing the Acceptance Protocol without reservations, confirming the delivery and installation of the equipment.