(source: Electronics World, Apr. 1968)
8 ways hp protects dc power supplies ... and your load
Rectifier Damping Network ... Protects downstream elements against short duration input line transients.
Preregulator Overvoltage Limit ... Protects load against excessively high output voltage.
Series Regulator Diode ... Protects series regulator against reverse voltage from external source (active load or parallel power supply).
Back-up Current Limit ... Protects load by pro viding back-up current limit, in case primary current limit fails or series regulator voltage becomes excessive.
Amplifier Input Clamp Diodes ... Protects voltage amplifier by limiting its input to less than 1 volt during violent output changes.
Sensing Protection Resistors ... Protects load from receiving full rectifier voltage if remote sensing leads or straps are accidentally open circuited.
Output Diode ... Protects the power supply against reverse output voltage from external source (active load or series power supply).
Crowbar Circuit *... Protects independently of any other power supply malfunction by providing fast clampdown of undesired overvoltage.
A Constant Voltage /Constant Current supply with automatic crossover inherently protects by providing adjustable current limiting in constant voltage operation and adjustable voltage limiting in constant current operation. The diagram shows eight additional protective features used in hp MPB-5 Series medium power bench supplies.
These protective features, in fact, are typical of those found in all hp DC power supplies. If you want to know more about the hp approach to power supply design, we'll be glad to send you our 1968 Handbook and Catalog combination. For the copy, call your local hp field representative or write Hewlett-Packard Company, 100 Locust Avenue, Berkeley Heights, New Jersey 07922 ; Europe : 54 Route des Acacias, 1211 Geneva 24.
Hewlett-Packard POWER SUPPLIES
