Alpha Technologies ACS HP Series - Manual (Page 7)

Preliminary
7
AIP900-0012-B0-001 Rev. A (01/2012)
Utility Power Connection Notes
Connecting to the utility should be performed only by qualified service personnel and in compliance with local
electrical codes. Connection to utility power must be approved by the local utility before installing the system.
Equipment Grounding Connection Notes
In order to provide a ready, reliable source of backup power it is necessary to connect the system to an effective
grounding and Earthing system that not only provides for the safety of the service personnel responsible for its
operation and maintenance, but also facilitates the proper operation and protection of the equipment within the
network. Such a grounding system provides protection with respect to operator safety, system communication,
and equipment protection.
Low impedance grounding is mandatory for personnel safety, critical for the proper operation of the system
and must be in place and connected to the system before the supply cables are connected.
SAFETY GROUND
The safety ground is a two-part system, comprised of the utility service and the ACS HP Series Battery
Charging system.
1. Utility service
As a minimum requirement for the protection of equipment, the local utility service must provide a low-
impedance path for fault current return to Earth. This must meet or exceed the requirements of the US
National Electrical Code or the Canadian Electrical Code. The connection between the system and the
utility must also meet or exceed the requirements of the US National Electrical Code or the Canadian
Electrical Code.
2. The grounding system
The grounding system consists of a low-impedance connection between the enclosure and an Earth
Ground (located at least 6’ away from the Utility Earth connection).
This impedance between the system and Earth must not exceed 0.1 Ohms.
Lightning Strike Ground
Lightning strikes, grid switching, or other aberrations on the power line and/or communications cable
have the potential to cause high-energy transients which can damage the powering or communications
systems. Without a low-impedance path to ground, the current, when traveling through wires of varying
impedance, produce damaging high voltage. The most viable method available to protect the system from
damage is to divert these unwanted high-energy transients along a low-impedance path to ground. A low-
impedance path to ground prevents these currents from reaching high voltage levels and posing a threat
to equipment. The single-point grounding system provides a low-impedance path to ground, and the
key to its success is the proper bonding of the ground rods, so the components of the grounding system
appear as a single point of uniform impedance. We recommend the use of a surge arresting device
electrically bonded to the ACS HP Charger Ground System.
Power Connection
WARNING!