Integrated Blocking Diode

The Integrated Blocking Diode Option (+BD) provides an internally heat-sunk protection diode on the positive output terminal of a MagnaDC programmable DC power supply. This diode protects the product's output from reverse voltage up to 1200 Vdc. All voltage sensing is performed after the protection diode—at the product's output terminals—making the diode's operation completely transparent to the performance of the power supply.

The +BD option is recommended for applications where there is significant back-emf or the possibility of a DC output voltage that could exceed the power supply's output voltage rating, such as:

  • DC motor drives
  • Battery and capacitor charging
  • Large electromagnets

In these applications, the integrated blocking diode can be used to prevent back-emf from the energy stored in the load into the power supply's output. Furthermore, the integrated blocking diode will prevent the power supply's internal bleed resistance from discharging the energy storaged in the load when the power supply is off or in standby.

The +BD option is available for the TS Series, MS Series, and MT Series models with maximum output voltage rating from 125 Vdc to 1000 Vdc.

Table 1. Specification for Integrated Blocking Diode (+BD) option
Reverse Voltage Rating
Models Rated 125 Vdc to 1000 Vdc
1200 Vdc
Reverse Voltage Rating
Models Rated Below 125 Vdc
200 Vdc
Additional Losses
Models Rated 125 Vdc to 1000 Vdc
Up to 1.4%
Additional Losses
Models Rated Below 125 Vdc
Up to 2.5%