Comtech EF Data SMS-458B - Manual (Page 85)

SMS-458B Modem Protection Switch Revision 2
Theory of Operation MN/SMS458B.IOM
4–25
4.8 Power Supply
4.8.1 General
The power supply modules fit into slots 1 and 7 of the upper-front section of the switch
chassis (Figure 4-12). (In slot 7 the supply is inverted.)
The supplies are enclosed in a 10.5 x 3.5 x 2.5-inch wide metal frame that encloses the
power supply assembly, provides power switch access, and secures in the chassis.
To turn on the power supply, press the switch toward the “1” symbol on the front of the
frame.
The switch can operate with only one power supply turned on, but an M:N fault will
indicate that the other power supply is faulted.
The frame can accommodate many different manufacturers power supplies, thus
providing for different power input specifications.
4.8.2 Specifications
120 VAC and 220 VAC Operation
Input voltage
90 to 264 VAC
Automatic selection for 110 or 220V operation
Input Frequency 47 to 63 Hz
Output Voltages and Current Capacity + 5V at 5A
+12V at 0.5A
-12V at 0.5A
Note: -48 Vdc operation is optional, and specifications will be provided upon request.