IS2020RKPSG3A VME Rack Power Supply
The VME rack power supply, IS2020RKPSG3A mounts on the side of the VME control and interface modules. It supplies + 5, ± 12, ± 15, and ± 28 V dc to the VME backplane.
Two supply input voltage selections are also available. There is a 125 V dc input supply that is powered from a Power Distribution Module (PDM) and a low voltage version for 24 V dc operation.
Operation of IS2020RKPSG3A
The VME Rack power supply IS2020RKPSG3A has only one user control, the power switch, and three status LED indicators. The power switch provides front control of the power supply output voltages and when toggled serves as a fault reset. The yellow, red, and green LEDs indicate the status of the input power, fault presence, and normal operation.
The front panel power switch of IS2020RKPSG3A is a locking type that must be pulled out to change position. So this switch is a low voltage control to enable or disable the output voltages. If the red LED is ON indicating a fault condition the power switch can be toggled OFF and then back ON again to clear the fault. The fault will only be cleared if the condition that caused it no longer exists.
When the power switch is OFF, the yellow LED will indicate the status of the input power of IS2020RKPSG3A. So if this LED is ON there is power present on the supply input connector. For the newer design, the yellow LED will only turn ON if the input voltage is above the input under-voltage fault threshold.
This LED will only be ON if there is the input power, the power switch is ON and a fault has been detected.
Green LED/Status Output of IS2020RKPSG3A:
If there is the input power to IS2020RKPSG3A, the power switch is ON, and there are no detectable faults, the Green LED will be ON. The newer designs also have a status output that mimics the status of this LED. The status output is a NO solid-state relay contact, that will be CLOSED when the green LED is ON.