Keysight Technologies N69100 Series, Руководство по эксплуатации и обслуживанию

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Programming Output Protection
Set the Over-Voltage Protection
Set the Over-Current Protection
Output Watchdog Timer
Clear Output Protection
Introduction
Keysight APS models have many protection functions. These functions disable the output to protect
the device under test (DUT) as well as the power supply. A front panel status indicator will turn on
when a protection function has been set. Most protection functions are latching, which means that
they must be cleared once they have been set.
All protections cause a high impedance output disconnect. The output is disconnected
without actively sinking current, so any voltage discharge of the DUT depends on the
DUT characteristics. The DUT and load lead inductance must be within the specified
hardware limits to safely absorb any stored energy. Refer to the Maximum Load
Inductance limits under
Supplemental characteristics .
Of the following protection functions, the OV, OC, PROT, and INH are user-programmable.
OV Over-voltage protection compares the voltage measured by the sense leads to the user-
programmed positive OVP level. If the sense voltage exceeds this level the unit goes into a latched
protection state. OV protection is always enabled.
OV- Negative over-voltage protection trips if the remote sense leads are accidentally reversed. This
protection minimizes the resulting rise in output voltage by comparing the voltage measured by the
sense leads to a fixed negative voltage level of 20% of the unit's rated voltage. If the sense voltage
exceeds this level the unit goes into a latched protection state. OV- protection is always enabled.
OC Over-current protection can be enabled or disabled. When enabled, the unit goes into a latched
protection state when the output current reaches the current limit setting. This prevents persistent
operation in current limit when operating in voltage priority mode.
OP+ Positive over-power protection compares the output power to the rated sourcing power. A OP+
protection occurs when the rated power threshold is exceeded. OP+ protection is always enabled.
OP- Negative over-power protection compares the sinking power to the rated sinking power. A OP-
protection occurs when the rated power threshold is exceeded. OP- protection is always enabled.
OT Over-temperature protection monitors a number of internal temperatures and compares them to
pre-defined temperature limits. If an internal temperature exceeds the pre-defined limit, the unit goes
into a latched protection state. The
OUTP:PROT:TEMP:MARG? query can be used to return the
margin remaining between the temperature sensor reading and the over-temperature trip level. OT
protection is always enabled. Note that If an over-temperature condition occurs on the AC input
4 Using the DC Power System
108 Keysight N69100 Series Operating and Service Guide