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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.
Power Level | 1.5 kW to 8 kW | 1.5 kW to 8 kW |
Max Output Voltage Rating | < 16 Vdc or > 1000 Vdc | ≥ 16 Vdc or ≤ 1000 Vdc |
Bleeder Resistance | 50 watts | 25 watts |
Constant Power | No | Yes |
Power Level | 2 kW to 10 kW | 2 kW to 10 kW |
Max Output Voltage Rating | < 16 Vdc or > 1000 Vdc | ≥ 16 Vdc or ≤ 1000 Vdc |
Bleeder Resistance | 50 watts | 25 watts |
Constant Power | No | Yes |
Power Level | 5 kW to 15 kW | 5 kW to 15 kW | 20 kW and 25 kW | 20 kW and 25 kW | 20 kW and 25 kW | 20 kW and 25 kW | 30 kW | 30 kW | 40 kW | 40 kW | 50 kW | 50 kW |
AC Input Voltage | All | All | 208/240 Vac | 208/240 Vac | 380/415 Vac or 440/480 Vac | 380/415 Vac or 440/480 Vac | All | All | All | All | All | All |
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 Resistance | 50 watts | 25 watts | 100 watts | 50 watts | 50 watts | 25 watts | 100 watts | 50 watts | 100 watts | 50 watts | 100 watts | 50 watts |
Constant Power | No | Yes | No | Yes | No | Yes | No | Yes | No | Yes | No | Yes |
Power Level | 30 kW | 30 kW | 45 kW | 45 kW | 60 kW | 60 kW | 75 kW | 75 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 watts | 50 watts | 150 watts | 75 watts | 200 watts | 100 watts | 250 watts | 125 watts |
Constant Power | No | Yes | No | Yes | No | Yes | No | Yes |
Power Level | 100 kW to 250 kW |
Max Output Voltage Rating | All |
Bleeder Resistance | 500 watts |
Constant Power | No |
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