Belden Grass Valley Kayenne K-Frame, Инструкция по установке и обслуживанию

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KAYENNE K-FRAME — Installation & Service Manual 83
K-Frame Compact Power Supply AC Requirements
a choice between high line or low line operation, the user should consider
the advantages and disadvantages of each power sourcing scheme.
K-Frame Compact Power Supply AC Requirements
The K-Frame chassis has provision to support up to two hot swappable
power modules. These convert the AC line input to 48V DC for the Video
Processor Frame. The cells for the two modules (referred to as left and
right) are identical and either or both cells can have a module installed.
Each cell has its own AC line cord. The supplies are power factor corrected
and automatically accommodate low line (120V nominal) or high line
(240V nominal). The power supplies have a rating of 100 – 240 volts,
although it is designed and tested for a range of 90 to 264 volts to accom-
modate under and over voltage conditions. A Compact K-Frame is sup-
plied with one power module. A second power module can be fitted as a
redundant power supply option.
About Low Line (120V) Operational Considerations
If low line (120V) operation is used (mostly in North America) three char-
acteristics of the switcher should be kept in mind when provisioning AC
power for the system, which will result in the most reliable system possible:
• Consider brown-out—Modern switching power supplies are constant
power devices and as such, unlike resistive loads, the input current
increases as the input voltage decreases.
• Consider power supply failure—If two or three power modules are
present, they will load share. For instance, if two modules are fitted and
the total AC line current is 10 amps, each of the two line cords will draw
about 5 amps. If one supply fails, the other supply takes up the entire
load. At this point, one line cord will draw 0 amps and the other cord
will draw 10 amps.
• Consider future options—The total AC power consumption is signifi-
cantly influenced by the number and type of hardware options
installed. This includes the number of MEs, Inputs, Outputs, and
Modular I/Os.
About High Line (208V-240V) Verses Low Line (120V) Operations
North American users usually have a choice to use low line (120 volts) or
high line (208-240 volts) as the AC source. If Lo line is used, a Compact
K-Frame with all options installed and running at 120 volts will draw a
total of approximately 9 amps from the line cords. At 100 volts, this
increases to approximately 10 amps. This load will be evenly distributed