Output bleed resistance

The MagnaDC power supply output consists of a large bank of capacitors used to filter output ripple. In parallel with these capacitors, a resistive bleeder circuit is provided to discharge the capacitors to safe levels when the power supply is not in use. The bleeder circuit is transparent to the product's voltage and current measurements. As the output of the power supply is regulated at the product's output terminals, the bleeder will be out of the circuit while the supply's output is enabled. When the power supply is in standby or switched off, the bleeder circuit will apply a load on the DC bus. If a discharge into the power supply's output is undesired, a blocking diode will prevent, for example, batteries or capacitors connected to the DC bus from bleeding into the power supply's output when the power supply is in standby or turned off.

The amount of bleed resistance varies by power level and the model's peak output voltage rating. While the high voltage or high power product utilize passive resistance rated for the peak voltage of unit, the low- to medium-voltage products utilize a constant power electronic bleeder, providing near equal loading at all voltage levels. Table 1 provides the integrated bleed resistance for the MagnaDC rack-mount products. Table 2 provides the integrated bleed resistance for MagnaDC floor-standing products.

Table 1. Output bleed resistance for SL Series MagnaDC programmable power supplies.
Power Level1.5 kW to 8 kW1.5 kW to 8 kW
Max Output Voltage Rating< 16 Vdc or > 1000 Vdc≥ 16 Vdc or ≤ 1000 Vdc
Bleeder Resistance50 watts25 watts
Constant PowerNoYes
Table 2. Output bleed resistance for XR Series MagnaDC programmable power supplies.
Power Level2 kW to 10 kW2 kW to 10 kW
Max Output Voltage Rating< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
Bleeder Resistance50 watts25 watts
Constant PowerNoYes
Table 3. Output bleed resistance for TS Series MagnaDC programmable power supplies.
Power Level5 kW to 15 kW5 kW to 15 kW20 kW and 25 kW20 kW and 25 kW20 kW and 25 kW20 kW and 25 kW30 kW30 kW40 kW40 kW50 kW50 kW
AC Input VoltageAllAll208/240 Vac208/240 Vac380/415 Vac or 440/480 Vac380/415 Vac or 440/480 VacAllAllAllAllAllAll
Max Output Voltage Rating< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
< 16 Vdc or
> 1000 Vdc
≥ 16 Vdc or
≤ 1000 Vdc
Bleeder Resistance50 watts25 watts100 watts50 watts50 watts25 watts100 watts50 watts100 watts50 watts100 watts50 watts
Constant PowerNoYesNoYesNoYesNoYesNoYesNoYes
Table 4. Output bleed resistance for MS Series MagnaDC programmable power supplies.
Power Level30 kW30 kW45 kW45 kW60 kW60 kW75 kW75 kW
Max Output Voltage Rating< 16 Vdc or > 1000 Vdc≥ 16 Vdc or ≤ 1000 Vdc< 16 Vdc or > 1000 Vdc≥ 16 Vdc or ≤ 1000 Vdc< 16 Vdc or > 1000 Vdc≥ 16 Vdc or ≤ 1000 Vdc< 16 Vdc or > 1000 Vdc≥ 16 Vdc or ≤ 1000 Vdc

Bleeder Resistance

100 watts50 watts150 watts

75 watts

200 watts100 watts250 watts125 watts
Constant PowerNoYesNoYes

No

YesNoYes
Table 5. Output bleed resistance for MT Series MagnaDC programmable power supplies.
Power Level100 kW to 250 kW

Max Output Voltage Rating

All

Bleeder Resistance

500 watts
Constant PowerNo