Technical Product Specification
Intel® Server System P4000IP and Intel® Workstation System P4000CR Family TPS System Power Sub-system
46 Intel order number G38159-002 Revision 1.2
2.2.5.1 Current Limit (OCP)
The power supply shall have current limit to prevent the outputs from exceeding the values
shown in table below. If the current limits are exceeded the power supply shall shutdown and
latch off. The latch will be cleared by toggling the PSON
#
signal or by an AC power interruption.
The power supply shall not be damaged from repeated power cycling in this condition. 12VSB
will be auto-recovered after removing OCP limit.
Table 41. Over Current Protection
Output Voltage
Input voltage range
Over Current Limits
+12V
90 – 264VAC
140A min; 170A max
12VSB
90 – 264VAC
2.5A min; 3A max
2.2.5.2 Over Voltage Protection (OVP)
The power supply over voltage protection shall be locally sensed. The power supply shall
shutdown and latch off after an over voltage condition occurs. This latch shall be cleared by
toggling the PSON
#
signal or by an AC power interruption. The values are measured at the
output of the power supply’s connectors. The voltage shall never exceed the maximum levels
when measured at the power connectors of the power supply connector during any single point
of fail. The voltage shall never trip any lower than the minimum levels when measured at the
power connector. 12VSBwill be auto-recovered after removing OVP limit.
Table 42. Over Voltage Protection (OVP) Limits for 1200W PSU
Output Voltage
MIN (V)
MAX (V)
+12V
13.3
14.5
+12VSB
13.3
14.5
2.2.5.3 Over Temperature Protection (OTP)
The power supply will be protected against over temperature conditions caused by loss of fan
cooling or excessive ambient temperature. In an OTP condition the PSU will shut down. When
the power supply temperature drops to within specified limits, the power supply shall restore
power automatically, while the 12VSB remains always on. The OTP circuit must have built in
margin such that the power supply will not oscillate on and off due to temperature recovering
condition. The OTP trip level shall have a minimum of 4C of ambient temperature margin.
2.2.6 Control and Indicator Functions
The following sections define the input and output signals from the power supply.
Signals that can be defined as low true use the following convention: Signal
#
= low true
2.2.6.1 PSON# Input Signal
The PSON
#
signal is required to remotely turn on/off the power supply. PSON
#
is an active low
signal that turns on the +12V power rail. When this signal is not pulled low by the system, or left
open, the outputs (except the +12VSB) turn off. This signal is pulled to a standby voltage by a
pull-up resistor internal to the power supply.