Bleed Circuit

 

 

 

 

 

 

 

In a DC power supply, even when the output is turned off, voltage often remains between the output terminals. This residual voltage is typically caused by the presence of filter capacitors, which store energy and lack a means to dissipate it once the equipment is powered off.

Bleed Resistor

 

 

For safety purposes, it is essential to have a method to discharge any remaining energy to prevent personnel injuries in case anyone accidentally touches the output terminal. This measure also serves to protect the Device Under Test (DUT). As depicted in Figure A, electrons retained in the capacitor can still produce voltage even when the output is turned off.

 

 

Figure A

 

 

 

 

And the most common way is using the bleed resistor connected in parallel to dissipate the power into heat. As depicted in Fig B, the bleed resistor helps to drain off the current from the capacitor to expedite the voltage drop to a safe level.

 

 

Figure B

 

 

 

 

Bleed Resistor Control

 

However, for some applications, users may prefer not to install the Bleed Resistor permanently in the circuit. Therefore, it would not be practical to remove the resistor and then reinstall it every time it is needed. To resolve this issue, we should use a DC power supply equipped with a built-in Bleed Resistor, which can control the Bleed Circuit function through the configuration settings, as depicted in Fig. C.

 

 

Figure C

 

 

 

 

 

 

In addition, bleed resistor also allows for smoother voltage regulation of the power supply as the bleed resistor acts as a minimum voltage load.

 

 

The Bleed Circuit function is supported in the following products, please visit the link below for more product information:

 

 

 

 

 

PSW www.gwinstek.com/en-global/products/detail/PSW-Series

PSW-Multi www.gwinstek.com/en-global/products/detail/PSW-Multi

PFR www.gwinstek.com/en-global/products/detail/PFR-100

PPX www.gwinstek.com/en-global/products/detail/PPX-Series

PSU www.gwinstek.com/en-global/products/detail/PSU-Series

 

 

 

 

 

 

 

Contact Us:

 

Diana

Digital Service Specialist  

E-mail: diana@goodwill.com.tw  

 

 

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