Regulated Power Supply 30V 5A

This is a Regulated 0-30 V DC Power Supply manufactured by me in small numbers, 0-30V 5A and 5V -5A. It had a Switching Preregulator. This keeps the Vce across Transistor Bank at the Back of Instrument, at the lowest possible level, in order to keep them Cool. When Vce and Ic both are more in a Power transistor it will get heated more, then the efficiency of power supply is low.

The Output had both Constant Current Control and Constant Voltage Control. The CC control is also a Short circuit protection. The Output was protected from outside voltages damaging output circuits even when equipment is switched off. The back panel is a finned anodized black aluminum heat sink with many transistors.

I looked for the circuits to scan them, i could not find it. I made-n-sold quite a few of them years ago. All of them work well even today as i over-rated most components. The cabinet was Steel for EMI-RFI Immunity, it was painted with Stipple Matt Powder Coating, the Cabinet maker had just learnt to give such a finish to his boxes.

Read more

• Electronics Cooling
• Heat sinks for transistors
• ESP - Heatsink design and transistor mounting
• Technical Papers
• Heat sink - Wikipedia, the free encyclopedia
• Power Supply Adjustable 30
• 3-30 V/2.5 A Stabilized power supply
• Small Variable power Supply
• Power Supplies
• The educational encyclopedia, Supplies
• Build A 10 Amp 13.8 Volt Power Supply
• Bench Top Power Supply, 30V - 10amp
• 40A Power Supply Unit
• Power Design Section

Study these applications at IRF Applications and ST Application Segments.

Transistor Beta and Vce Tester

This was a Beta Hfe and Vce Measuring Instrument used in Incoming Inspection of Power Transistors made by me 16 years back.

Related Resources -

• Testing Transistors with Ohmmeter
• The Transistor Curve Tracer
• Transistors as current amplifiers
• Transistors Tutorial
• Transistors - The Electronics Club
• Basic Testing of Semiconductor Devices
• Full Featured Transistor Tester

Tera Ohm Meter and Insulation Tester

This is a 20 Tera Ohm Insulation Tester I made around 20 Years Back. It had even Polarization Index for Transformer Insulation. It generated 1000V DC Regulated Voltage and the pA leakage Current was Measured. See more here Insulation tester or Tera ohm meter.

A regulated, low ripple, high voltage of very low current capability is applied by instrument on a DUT (device under test). The leakage current in nA or pA (picoamps, nanoamps) is measured and readout, The Innovation i did was to measure the current in Vref and not Vin of ICL7107, this made the 1/x computation.

Also using the ICL7650 Chopper Stabilized amplifier must be done as shown in data sheets with grounded guard rings. pA will leak on the PCB itself if layout is not done keeping this in mind.

• What is Insulation Testing?
• Insulation testing
• K8CU's HV Tester
• A Review of Polarization Index and IEEE Std. 43-2000
• Applications - Insulation Resistance Testing: Branom Instrument
• FAQ's - Insulation Resistance Test
• High Voltage Insulation Tester - TeraOhm
• BK Precision Insulation Tester Models 307 and 308
• BK Precision Insulation Tester Model 300