Xantrex Technology PROsine 2.0 - Manual (Page 55)

Step 5: Configuring the Output Neutral Bonding System
445-0089-01-01 3–13
Step 5: Configuring the Output Neutral Bonding System
AC Output Neutral-to-Ground Bonding System
The PROsine provides an installer-defeatable system that automatically connects
the neutral conductor of the inverter AC output circuit to safety ground
(“bonding” it) during inverter operation, and disconnects it (“un-bonding” it)
when the PROsine has connected to AC shorepower. This system is designed to
conform to installation codes that require single-phase AC sources such as
inverters and generators to have their neutral conductors tied to ground in the
same way that the neutral conductor from the utility is tied to ground.
These same codes specify that the neutral can only be connected to ground in one
place at any one time. Any AC source feeding the PROsine is required to have its
neutral already connected to ground. Therefore, to keep from connecting the
neutral to ground in a second place, the PROsine transfer relay breaks its own
neutral ground connection when connected to shorepower.
This automatic neutral-to-ground bonding system is suited for installations in
which the AC shorepower source is known to have a bonded neutral. This will be
the case in most situations: in a utility feed after the AC source panel, at an RV
park hook-up, at a marina’s shorepower hook-up, or with a generator with a
bonded neutral.
In some installations, however, the AC shorepower source will not have a bonded
neutral. This is true on some generators and it is true in certain utility-feed
situations. To accommodate these situations, the PROsine automatic neutral
bonding system can be defeated, so the PROsine will not bond the neutral in any
mode of operation. This allows the installer to bond the neutral in the AC load
panel to provide the required single-point bonding of the neutral.
To enable and disable the automatic AC output neutral-to-ground bonding
system
You enable and disable the system using a screw in the AC wiring compartment,
identified as the “Invert Mode Output Neutral-to-Ground Bonding Screw”. (See
Figure 3-3.) This screw is identified with a label that indicates two different holes
that the screw can be mounted in. One hole is identified as the one that enables the
automatic bonding system, and the other hole defeats it so that the neutral is not
bonded by the PROsine in any mode.
WARNING: Fire and Shock hazard
AC neutral bonding system settings should only be changed by a qualified installer aware
of the implications of the changes. Disconnect all AC and DC sources before working in
the AC wiring compartment or before making a setting change.