standards and guidelines for communication sites - Radio And ...

STANDARDS AND GUIDELINES FOR COMMUNICATION SITES AC POWER SPD REQUIREMENTS
Electrical meter and main
service disconnect are
located on the cabinet
exterior, an adjacent
pedestal or utility pole.
See Notes 1 & 2
Main Service
Disconnect
Meter
Utility Feed
AC
240/120 Single Phase
Block Diagram of AC Power Distribution, SPDs' and Alarm Circuits for pole or pad mounted cabinet(s) for a complete system with
independent dedicated service and a standby generator.
NOTES:
To Alarms Panel
(Recommended)
SPD
(Surge
Suppressor)
Type 2 MOV
Main
Panelboard
with a main
breaker
See Note 2
To Alarms
Panel
Automatic
Transfer
Switch
See Note 2
Generator
To Alarms Panel
(Recommended)
SPD
(Surge Suppressor)
Type 1 SAD/MOV
Utility
Panelboard
Non-Critical
Loads
Type 3 SPD optional when greater
than 10 conductor feet from
panelboard.
To Alarms Panel
1. The main service disconnect may be located outside the pole or pad mounted equipment cabinet, typically on the cabinet
exterior, an adjacent pedestal or utility pole. This may also be incorporated within the main panelboard.
2. The main panelboard, Type 2 or optional Type 1 SPD and Automatic Transfer Switch may be located outside the cabinet(s). (If located outside
the cabinet these shall be in weatherproof enclosures.)
3. The UPS may not be present in which case all loads will be fed from the Utility Panelboard.
4. The Type 1 and Type 2 SPDs shall be installed per the manufacturer's installation instructions.
5. All conductors between the SPDs and the associated disconnecting device shall be as short as possible and routed
together with a minimal number of bends or angles of less than 90 degrees.
6. The SPD disconnecting devices should be installed in the top most space available in the Panelboards.
7. Installation of Type 3 SPDs on critical and non critical loads, although optional, is recommended where the level of exposure
is high.
FIGURE 7-16 SPD INTERCONNECT BLOCK DIAGRAM ‘O’
Pole or Pad mounted equipment cabinet.
68P81089E50-B 9/1/05 7-25
UPS
See Note 3
UPS
Panelboard
Type 3 SPD
optional
Critical
Loads