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4.3.4 Power Supply Faults
The Power Supply Fault circuit monitors the 28 VDC, ± 12 VDC and 5 VDC power supplies and
produces a fault indication should any voltage level deviate from normal operating parameters. Each
power supply voltage output is monitored and displayed to indicate the power supplies are operating
within design parameters. Some units may have Green Status LED Indicators in addition to the
Controller Display. Should any power supply voltage deviate from the design parameters, the
corresponding power supply fault will be displayed
4.3.5 Mismatch Protection
The SMX100 is designed to operate with a tuned 50 Ohm load and should any mismatching of the 50
Ohm load occur, the Reverse Power, also called Reflective Power, will increase producing a high
VSWR. The SMX100 microprocessor monitors the Reverse Power levels by utilizing a Dual
Directional Coupler and begins to turn down the gain of the preamplifier when the Reflected Power
exceeds 40%. The Reverse Power is also displayed on the LCD Display for operator monitoring for
any mismatched load.
4.3.6 Short Circuit Protection
The SMX100 utilizes three different power supply voltages, + 28 VDC, ± 12 VDC and the
+ 5 VDC, each of the power supplies are designed with a short circuit and overload protection
device.
