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Plexus 9000 Planning and Engineering Guide
Planning for Installation
Section 130-200-000
Issue 5, January 24, 2003
Telica, Inc.
6-11
6.1.6.2
Frame/Chassis Ground for the Power and Alarm Panel
The frame/chassis ground connection for the Power and Alarm Panel
should be terminated to the main ground bar. Each Power and Alarm
Panel is connected to the earth/frame ground via a 6 AWG wire, with a
double-hole lug at the chassis end. Non-oxidizing grease should be put on
the ground lugs to ensure a good connection.
6.1.7 Power
Requirements
6.1.7.1
Basic Power Requirements
For redundancy, each Plexus 9000 requires that power be provided from
two separate (A and B) 50-amp breakers at -48 Vdc (for a total of four
wires). Therefore, each breaker requires wiring sized to handle up to
50-amps at -48 Vdc. Refer to
for
power requirements. The A
and B power returns provide the return path for all –48 Vdc loads. This
path is isolated from chassis grounds.
The Telica shelf may be powered directly from customer-furnished power
distribution (home run) or via a power and alarm panel mounted in the
equipment bay. Telica can provide power and alarm panels as necessary.
Table 6.1-F. Plexus 9000 Power Specifications
Requirement
With DS-1/DS-3
With Octal DS-3
Input voltage
-40 Vdc to –56.7 Vdc
-40 Vdc to –56.7 Vdc
Thermal output
*
up to 2730 BTUs /hr/shelf
up to 4505 BTUs /hr/shelf
Current draw
*
20 Amperes per shelf
33 Amperes per shelf
Power consumption
*
800 Watts
1320 Watts
*
Fully loaded at 40 Vdc.
T11-B
6.1.7.2
Power and Alarm Panel (PAP)
A Telica power and alarm panel, which is 1 RU (1.75 inch) high and
normally mounted in the top position of the relay rack, may be used to
provide power to the Plexus 9000. Each Plexus 9000 requires that power
be provided from two separate (A and B) 50-amp (at –48 Vdc) breakers.
The input power wire sizing at the power panel must support a 150-amp
bus rating and thus must have a minimum of size #1 AWG. The primary
system breaker must have a minimum rating of 120 amps and the voltage
drop allowable between the Telica PAP and the power plant must be
limited to 2.5V.