5
2.0 INSTALLATION
©2000 Xantrex/Trace Engineering
Pre-Installation
(continued)
Grounding
:
AC Grounding
The Trace ST unit should be connected to a grounded, permanent wiring system.
DC Grounding
The negative PV conductor should be bonded to the grounding system at only one point in the
system. The size for the conductor is usually based on the size of the largest conductor in the DC
system. Negative/ground bonding is accomplished by factory wired PVGFP breakers (when this
option is installed) or a factory installed grounding block (when PVGFP is not installed).
PV Arrays:
The ST unit is optimized to work with 4-each, 12 volt nominal crystalline PV modules in series
(48 VDC nominal), or various combinations of amorphous, thin film PV modules. Ensure the PV
array used in the system operates within the MPPT operational window.
The solar array connected to the ST Series inverter should have a minimum of 50 volts DC
open-circuit in full sunlight conditions. Crystalline solar arrays configured for 48 volts DC nominal will
have a open-circuit voltage in the area of 84 volts DC in full sunlight. The maximum peak power
tracking (MPPT) software controls the output of the solar modules, under loaded conditions, in the
42-85 volts DC range (full inverter output power occurs between 5285 VDC). Other array voltage
will either not operate the inverter or will not allow maximum harvest of the suns energy.
WARNING: WHENEVER A PV ARRAY IS EXPOSED TO SUNLIGHT, A SHOCK HAZARD EXISTS
AT THE OUTPUT CABLES OR EXPOSED TERMINALS. TO REDUCE THE RISK OF SHOCK
DURING INSTALLATION, COVER THE ARRAY WITH AN OPAQUE (DARK) MATERIAL BEFORE
MAKING ANY CONNECTIONS.
Figure 3
Ground Bar Location
Ground Bar Location
(connect to solid earth ground)
ST1000 and ST2000 Models
ST1500 and ST2500 Models
