©
2017 Sensata Technologies
Page 36
Installation
2.7.7 Wiring
for
the Internal GFDI
The PT-100 charge controller is equipped with GFDI (Ground Fault Detection/Interruption) capability
and the normal factory default is with the GFDI feature enabled (DIP switch 2 is down). With the
GFDI enabled, the PV negative and battery negative lines must be wired so that they are
fl
oating
with respect to ground—the single point of ground for the DC system is made within the PT controller
through its internal 0.5-amp GFDI fuse. The GFDI fuse inside the PT-100 provides the system negative-
to-ground bond and is used to detect ground-faults in a negative grounded PV array system, which
is common in North American installations. See Section 4.5 for more information on the operation
of the Ground Fault Protection circuitry.
If an external GFDI device will be used in the PV system, then the controller’s internal GFDI feature
must be disabled (push DIP switch 2 to UP) and the GFDI fuse must be removed. See Section 5.5
for information on removing the GFDI fuse.
CAUTION:
If GFDI protection is enabled, the PV negative and battery negative circuits
are grounded inside the PT controller. DO NOT ground the PV negative or battery negative
circuits in any other location, or the GFDI protection feature in the PT-100 charge controller
will be defeated.
Info:
If multiple PT controllers are connected together (i.e., stacked), see Section 2-11
for information on setting up the GFDI for a multiple controller system.
2.7.7.1 GFDI
Label
In a photovoltaic system that has a Ground Fault Protection device, the NEC requires the installer
to apply a warning label near the ground fault indicator in a visible location, stating the following:
WARNING: ELECTRIC SHOCK HAZARD
IF A GROUND FAULT IS INDICATED, NORMALLY GROUNDED
CONDUCTORS MAY BE UNGROUNDED AND ENERGIZED.
When the photovoltaic system also has batteries, the same warning is also required to be posted
by the installer in a visible location at the batteries.
This warning sign/label(s) shall comply with Section 110.21(B) of the NEC, which states:
1. The WARNING label shall use the following colors: Black text with white and orange background.
2. The label shall be permanently af
fi
xed to the equipment and shall not be handwritten.
3. The label shall be of suf
fi
cient durability to withstand the environment where it is installed.
A label as shown in Figure 2-16 that complies with the NEC requirements is provided with the
PT-100.
Info
: When the PT controller’s ground fault protection circuit is enabled and a ground
fault is detected, the fault indicator comes on and
F12
is displayed on the PT controller.
Figure 2-16, Ground Fault Label
IF A GROUND FAULT IS INDICATED,
NORMALLY GROUNDED CONDUCTORS MAY
BE UNGROUNDED AND ENERGIZED.
WARNING
ELECTRICAL SHOCK HAZARD
PN: 62-0041 Rev A