|NI-DCPower (English | Japanese)|
Both channels on the NI PXIe-4154 are protected against overvoltage, inverse-voltage, overcurrent, and overtemperature conditions. These conditions cause protection circuitry to engage, which disables the output of the affected channel and disconnects the channel circuitry from the output connector pins. By internally disconnecting the output, it protects both the NI PXIe-4154 and the device under test. To clear the error condition, first identify the cause of the error and then reset the channel or device.
|Caution Do not apply voltages at the output that exceed the ratings of the NI PXIe-4154.|
Overvoltage protection (OVP) is enabled by default on both channels of the NI PXIe-4154. The protection circuit engages if the voltage at the Output + terminal exceeds the voltage setpoint by more than 2.5 V. The circuitry will not engage if the channel enters current compliance while sinking current.
OVP may be triggered inadvertently if you are configured for Remote Sense and either the sense lines are shorted together or any of the sense lines (Sense + and Sense - at the connector) get connected to the device under test (DUT) before their corresponding drive lines (Output + and Output - at the connector). This last scenario may happen when connecting/disconnecting the connector or when using a switch to connect to different DUTs and the order in which connections are done is not properly chosen.
NI recommends disabling the channel before making any connection changes. Once all connections between the NI PXIe-4154 and the DUT are properly done, the channel can be enabled. The channel can be enabled/disabled by using the niDCPower Configure Output Enabled VI or niDCPower_ConfigureOutputEnabled function.
An OVP error condition can be cleared by resetting the channel or device.
Inverse voltage protection helps protect each channel of the NI PXIe-4154 if it is connected to a voltage source with a negative polarity. The inverse voltage protection will trip when a voltage of -0.2 V (typical) is applied between Output + and Output - terminals when in local sense, and between Sense + and Sense - when in remote sense. An inverse voltage error condition can be cleared by resetting the channel or device.
Overtemperature protection ensures that the enclosure and component temperatures don't exceed safe operating limits. If an overtemperature condition occurs, the output channel can be reset after the failure condition is cleared. Refer to the NI PXIe-4154 Thermal Protection and Precautions topic for more information.
Both channels on the NI PXIe-4154 have output fuses to prevent excessive current from flowing into or out of the NI PXIe-4154. If the output fuse is blown for a channel, you will not get an error, but the output current will be limited to close to 0 A. The NI PXIe-4154 fuses are not user replaceable.