© National Instruments
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RMX Programmable Power Supplies User Manual
Output Terminal Insulation
Caution
Risk of electric shock. For safety reasons, even if the output terminal is
grounded, secure reinforced or double insulation with a capacity greater than or equal
to the isolation voltage of the RMX programmable power supply for the output
terminals (including sensing terminals) and load cables. Refer to Appendix A,
, for the isolation voltage of your model.
If cables with sufficient voltage rating cannot be obtained, use insulation tubes to
secure reinforced or double insulation with a capacity greater than or equal to the
isolation voltage of the RMX programmable power supply.
Confirm the voltage between any output terminal and ground is lower than the
isolation voltage of the RMX power supply.
The signal cable may burn out. If the RMX programmable power supply is to be
controlled through an external voltage (Vext), do not ground the external voltage
(leave it floating).
The cable and load that are connected to the output terminal (including the sensing terminal)
must have a reinforced or double insulation with a capacity that is greater than or equal to the
isolation voltage of the RMX programmable power supply with respect to the chassis. Isolation
voltage indicates the maximum allowed voltage that appears across the output terminal of the
power supply unit and the protective conductor terminal (chassis terminal).
When the Output Terminal is Not Grounded (Floating)
The output terminal of the RMX programmable power supply is isolated from the protective
conductor terminal. If you connect the GND wire of the power cord to the ground terminal of
the switchboard, the chassis of the RMX programmable power supply is set to ground potential.
Pins 5 to 13 (for external control and parallel operation) and 18 to 25 (for external control and
output monitoring) of the rear panel J1 connector are at approximately the same electric potential
as the RMX programmable power supply negative output terminal. Cables and devices that are
connected to these pins must have a reinforced or double insulation with a capacity greater than
or equal to the isolation voltage of the RMX programmable power supply.
