Series BOP Magnet Power Supplies (Inductive Load Models)

For guidance concerning whether to choose the optimized BOP-L version vs the standard BOP when operating with an inductive load, refer to Kepoc's Application Note BOP 004: When to Use BOP Standard or Optimized (L or C Suffix) to Drive Reactive Loads.

BOP L option (magnet power supply) units are designed to operate in a stable manner in Current or Current Limit Mode for loads up to 1 Henry. They are also stable with any R-L series load combination.

All specifications of the BOP L option unit (magnet power supply) in voltage mode are unchanged from the standard model. All specifications listed below are for L option (magnet power supply) models in Current Mode. All other specifications are identical to the standard BOP.

In current mode the bandwidth of the L option (magnet power supply) BOP is reduced modestly when operating with a resistive load. Correspondingly, the rise and fall time of the unit is increased somewhat (model dependent). Further, it is possible to reduce the bandwidth in current mode in a predictable way, using one customer installed component on the rear programming connector of the BOP.

For higher power BOP models (magnet power supplies) optimized for inductive loads, see Kepco's 1KW BOP-GL Series.

(1) All specifications listed are for inductive load models in Current Mode.
      All other specifications are identical to the standard BOP.
(2) Bandwidth specifications for units with GPIB control are somewhat reduced. Consult factory for details.
(3) 10% - 90%, Short-circuit.
(4) Short-circuit, Nominal Resistive Load.
(5) Load effect increases nonlinearly with frequency from the typical 0.5 mA in DC full scale
      (same as the standard unit) with the average rate listed.

If the load impedance at the working frequency multiplied by the peak value of current equals the voltage limit setting, it is recommended that the output voltage be kept below the voltage limit setting to avoid inducing a large distortion of output current. If the voltage limit is reached, the unit's bandwidth can be reduced by connecting an external film capacitor between pins 16 and 18 of the unit's programming connector (PC 12). The table below shows the effect that adding the external capacitor has on the 3dB bandwidth for resistive, resistive-inductive or inductive loads, with less than 10% tolerance (excluding the capacitor tolerance).