Penguin Computing Relion 1900e, Technical Manual

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Relion 1900e/2900e Manual
Revision 1.0 114
13.2.5 Capacitive Loading
The power supply shall be stable and meet all requirements with the following capacitive loading ranges.
Table 54. Capacitive Loading Conditions
Output MIN MAX Units
+12VSB 20 3100 µ F
+12V 500 25000 µ F
13.2.6 Grounding
The output ground of the pins of the power supply provides the output power return path. The output
connector ground pins shall be connected to the safety ground (power supply enclosure). This grounding
should be well designed to ensure passing the max allowed Common Mode Noise levels.
The power supply shall be provided with a reliable protective earth ground. All secondary circuits shall be
connected to protective earth ground. Resistance of the ground returns to chassis shall not exceed 1.0 m
Ω
.
This path may be used to carry DC current.
13.2.7 Closed loop stability
The power supply shall be unconditionally stable under all line/load/transient load conditions including
specified capacitive load ranges. A minimum of: 45 degrees phase margin and - 10dB-gain margin is
required. Closed-loop stability must be ensured at the maximum and minimum loads as applicable.
13.2.8 Residual Voltage Immunity in Standby mode
The power supply should be immune to any residual voltage placed on its outputs (Typically a leakage
voltage through the system from standby output) up to 500mV . There shall be no additional heat generated,
nor stressing of any internal components with this voltage applied to any individual or all outputs
simultaneously. It also should not trip the protection circuits during turn on.
The residual voltage at the power supply outputs for no load condition shall not exceed 100mV when AC
voltage is applied and the PSON# signal is de-asserted.
13.2.9 Common Mode Noise
The Common Mode noise on any output shall not exceed 350mV pk-pk over the frequency band of 10Hz to
20MHz.
13.2.10 Soft Starting
The Power Supply shall contain a control circuit which provides monotonic soft start for its outputs without
overstress of the AC line or any power supply components at any specified AC line or load conditions.
13.2.11 Zero Load Stability Requirements
When the power subsystem operates in a no load condition, it does not need to meet the output regulation
specification, but it must operate without any tripping of over-voltage or other fault circuitry. When the
power subsystem is subsequently loaded, it must begin to regulate and source current without fault.
13.2.12 Hot Swap Requirements
Hot swapping a power supply is the process of inserting and extracting a power supply from an operating
power system. During this process the output voltages shall remain within the limits with the capacitive load
specified. The hot swap test must be conducted when the system is operating under static, dynamic, and
zero loading conditions.
13.2.13 Forced Load Sharing
The +12V output will have active load sharing. The output will share within 10% at full load. The failure of a
power supply should not affect the load sharing or output voltages of the other supplies still operating. The