Magna-Power PQA200-50

Magna-Power Electronics’ PQ SERIES power supplies set a new standard for high-powered dc supplies. A combination of high and medium frequency power processing technologies improves response, shrinks package size, and reduces cost. PQ SERIES power supplies are current fed. Compared with conventional switching power supplies, these supplies can easily tolerate the punishment of the most rigorous applications.

PQ SERIES power supplies are fully programmable via resistance, voltage, current, or optional IEEE-488/RS232. While other supplies can remotely control only output voltage and current, PQ SERIES units also allow programming of over voltage and over current protection. Program lines are constantly monitored for range of operation. If a line should open or if a programmable input is set beyond that anticipated, the unit safely shuts down protecting the load.

PQ SERIES power supplies can operate as a voltage source or current source depending on the control settings and load conditions. If the power supply is operating as a voltage source and the load increases to a point beyond the current command setting, the power supply automatically crosses over to current mode control and operates as a current source at that setting.

Differential amplifiers isolate the programming lines from the dc output allowing programming at any distance from the load. Additional differential amplifiers are provided for master/slave series or parallel operation.

Diagnostic functions are contained directly within the supply’s control loop. Exclusive circuitry eliminates guesswork about which function has control -- voltage, current, or a fault condition. If the fault condition requires user attention, main power is disconnected and the diagnostic condition is latched into memory. Pressing the reset switch clears the memory. All diagnostic functions are monitored with optical isolators that can be paralleled for master/slave operation. Furthermore, control functions can also be set through optical isolators to allow simultaneous control of one or more PQ SERIES units. Programming switches in the rear of the supply enable internal operation of controls, external operation, or both.

PQ SERIES supplies have three levels of over voltage/current protection: shutdown of controlling insulated gate bipolar transistors (IGBT’s), disconnect of main power, and optional SCR crowbar. After an over voltage/current condition, the supply must be reset. Pressing the reset switch causes 1 the over voltage/current settings to be displayed on the front meters.

PQ SERIES power supplies have push button start/stop controls. These controls are electrically integrated to a mechanical contactor which operates with the electronic switches to break the ac mains when stop is commanded. Unlike competing products, an off means both an electrical and mechanical break in the power circuit — not a break in an electronic switch. Safety comes first at Magna-Power Electronics.