Generac Power Systems 005342-6, Руководство пользователя

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10
EMERGENCY CIRCUIT ISOLATION
METHOD
This prevents overloading the generator by keeping electrical
loads below the wattage/amperage capacity of the generator. If
the generator is powering only critical loads, within the wattage/
amperage capacity, during utility power outages, consider using
the emergency circuit isolation method.
Critical electrical loads are grouped together and wired into a sepa-
rate “Emergency Distribution Panel.” Load circuits powered by that
panel are within the wattage/amperage capacity of the generator
set. When this method is used, it is difficult to overload the gen-
erator. The transfer switch must meet the following requirements:
• It must have an ampere rating equal to the total amperage rating
of the emergency distribution panel circuit.
• Have it installed between the building’s main distribution panel
and the emergency distribution panel.
TOTAL CIRCUIT ISOLATION
METHOD
When a generator capable of powering all electrical loads in the
circuit is to be installed, use the “Total Circuit Isolation Method.” It
is possible for the generator to be overloaded when this isolation
method is employed. The following apply to the transfer switch in
this type of system.
• Ampere rating of the transfer switch must equal the ampere
rating of the normal incoming utility service.
• The transfer switch is installed between the utility service
entrance and the building distribution panel.
GROUNDING THE STATIONARY
EMERGENCY GENERATOR
The National Electrical Code requires the frame and external electri-
cally conductive parts of this equipment to be properly connected
to an approved earth ground and/or grounding rods. For that
purpose, a GROUND LUG (Figure 2.2) is provided on the genera-
tor mounting base. Consult a qualified electrician for grounding
requirements in the area. Grounding procedures must meet local
regulations.
 Do not connect the ground wire to any pipe
that carries a flammable or explosive sub-
stance – FIRE or an EXPLOSION may result.
Proper grounding helps protect personnel against electrical shock
in the event of a ground fault condition in the generator or in con-
nected electrical devices. In addition, grounding helps dissipate
static electricity that often builds up in ungrounded devices.
Figure 2.2 – Generator Grounding Lug (typical)
GENERATOR AC NEUTRAL
CONNECTIONS
The manufacturer uses an UNGROUNDED AC neutral. Grounding
is recommended only at the main service entrance. If the neutral
wire is grounded and one of the phase loads becomes grounded,
the excessive current opens the load circuit breaker or collapses
the generator field. The actual result depends on the electrical
characteristics of the particular installed generator.
TRANSFER SWITCH START SIGNAL
CONNECTIONS
If the generator is to be installed with a standard automatic transfer
switch, such as a GTS-type switch, it will be necessary to connect
the two-wire start control system.
Connect the two-wire start signal from the automatic transfer
switch to the automatic start connection, which is located in the
lower rear of the AC connection panel. Match wires 178 and 183
in the transfer switch to 178 and 183 on the terminal strip in the
connection box. The conductors for the two-wire start circuit must
be in their own conduit.
If the generator is to be installed with an HTS-type transfer switch,
a different connection method is needed.
Use shielded 2-wire communications cable (such a Belden
#9460) to make the connection from the HTS transfer switch to
the engine generator connection panel. This cable is to be routed in
a separate conduit between the HTS transfer switch and the engine
generator. The cable is to be connected as follows:
HTS transfer switch - 4 position terminal block, in the bottom of
the transfer switch enclosure (labeled "comm. Ports").
Engine generator - terminal strip located in the lower rear of the
AC connection panel. Connect the RS485+ and RS485- to the
respective terminals in switch and generator. Do not connect the
shield at transfer switch end.
Installation