Owner`s manual

36
If an electrical system has components
grounded at different points in the earth
(detail A), large voltage differences will
exist between these grounds during a
lightning strike. If this voltage appears
between the AC and DC side of the
inverter, it could fail. Likewise, if this
voltage appears between the different
components of an access control system,
the components can fail.
The first step in protection is to make
sure that all equipment in the system is
physically grounded at the same location
(detail B). This assures that there is no
voltage potential between grounds in the
system, which means there is no current
flow through the system.
All equipment involved in the system
should physically be located as close as
possible to one another. This reduces
the potential that is developed between
the ground site and the individual
components of the system during a
lightning strike. This single point
grounding (detail C) greatly reduces the
potential for lightning damage to
electrical equipment.
6.3 GROUNDING vs. LIGHTNING
Gate Operator Telephone Entry
Backup Power
System
Lightning Strike
Single Point Ground System
0 Volts0 Volts
Gate Operator Telephone Entry
Backup Power
System
Lightning Strike
Multi Point Ground System
Voltage DifferenceVoltage Difference
Gate Operator Telephone Entry
Backup Power
System
Ground Bus
Single Point Ground Bus System
Minimum #12 AWG
Minimum #6 AWG
NEMA Enclosure
AC Supply GND
DETAIL A
DETAIL B
DETAIL C