Since the use of this manual and the conditions or methods of installation, operation, use and
maintenance of the unit are beyond the control of Xantrex/Trace, the company does not assume
responsibility and expressly disclaims liability for loss, damage, or expense arising out of or any way
connected with such installation, operation, use, or maintenance.
This manual contains important safety instructions that should be followed during the installation
and maintenance of this product.
To reduce the risk of electrical shock, and to ensure the safe installation and operation of this
product, the following safety symbols have been placed throughout this manual to indicate
dangerous conditions and important safety instructions.
WARNING - A dangerous voltage or condition exists in this area.
Use extreme caution when performing these tasks.
AVERTISSEMENT - Une tension ou condition dangereuse existe dans cette zone.
Faire preuve dextrême prudence lors de la réalisation de ces tâches.
CAUTION - This procedure is critical to the safe installation or operation of the unit. Follow these
instructions closely.
ATTENTION - Cette procédure est essentielle à linstallation ou lutilisation
de lunité en toute sécurité. Suivre ces instructions de près.
NOTE - This statement is important. Follow instructions closely.
NOTE - Cette déclaration est importante. Suivre les instructions de près.
All electrical work must be done in accordance with local and national electrical codes.
Before installing or using this device, read all instructions and cautionary markings located in
(or on) the manual, the ST and the PV array.
Do not expose this unit to rain, snow or liquids of any type without the rain/weather shield
hood installed (optional on some models).
To reduce the chance of short-circuits when installing or working with the inverter or the PV
array, use insulated tools.
Remove all jewelry such as rings, bracelets, necklaces, etc., prior to installing this system.
This will greatly reduce the chance of accidental exposure to live circuits.
The ST unit contains more than one live circuit (PV array and AC line). Power may be present
at more than one source even when the circuit breakers are off.
This product contains no user serviceable parts. Return the unit to a Trace Authorized Service
Center for maintenance.
Wiring to the utility should only be done after receiving prior approval from the utility company
and performed only by a qualified electrician.
Completely cover the surface of all PV arrays with an opaque (dark) material BEFORE wiring
them. PV arrays produce electrical energy when exposed to light, and could create a
hazardous condition.
The Trace Sun Tie (ST) solar power conversion center is designed to convert a home or
business into a green power generating station. The ST unit converts solar electric (PV) power into
utility grade electricity which can be used by the home, or sold to the power company. Installing an
ST unit is as simple as mounting it to the wall and connecting a DC source (PV array), and the AC
output to the utility.
Standard Features
All-in-one Design
All necessary DC input and AC output connections, disconnects and circuit breakers are housed
within the STs easily installed, compact enclosure. A built-in LCD panel provides easy-to-read
system status and daily cumulative energy production information.
Uses Most Types of PV Technology
The ST is designed to take advantage of most types of solar electric technologies. The inverter
allows up to 120 VDC open circuit PV modules to be used so both crystalline and thin film PV
modules can be used.
Maximum Power Point Tracking
The inverter performs a power sweep every minute adjusting array voltage and current,
maximizing PV power generation. Maximum Power Point Tracking (MPPT) ensures the system
produces as much AC power as possible under any light condition.
High Efficiency and Long Life
The high frequency, solid-state design of the ST inverter is extremely efficient. When array
output is over 500 watts, the inversion process is over 90% efficient (with a peak efficiency of 94%).
The ST inverter has a design life of over twenty years.
Expandable
ST inverters may be connected in a parallel configuration for increasing net metering capacity.
The modular expandability of the ST Series allows for system growth.
UL Listed
The ST has complete on-board islanding protection and meets safety operating standards and
code requirements world wide. In North America, it is UL listed (UL 1741-First Edition) and cUL listed
to CSA C22.2 No. 107.1-95. NEC 690 building code requirements for PV may be met with the
optional ground fault protection (PVGFP).
Options
These features are included on some models:
PV array combiner board with six 20 amp max. protected inputs
Before installing the Trace ST unit, read all instructions and cautionary markings located in
this manual, on the PV array and on the main service panel.
NOTE: The Trace ST weighs approximately 35 pounds (depending upon configuration and model).
Always use proper lifting techniques during installation to prevent personal injury.
Mounting:
The Trace ST unit can be mounted outdoors with the optional Rain Shield (STRS).
wood screws and washers (supplied)
conduit and appropriate fittings
anchors for screws (material dependent)
AC Connections:
The inverters AC output breakers accept wire sizes from #614 AWG. Refer to the table
below for minimum recommended wire size.
Inverter
Model
ST1000
ST1500
ST2000
ST2500
AC Am ps
Output per
leg
4.25.214 AWG14 AWG12 AWG
6.37.814 AWG12 AWG10 AWG
8.310.414 AWG12 AWG10 AWG
10.41314 AWG12 AWG8 AWG
NEC Amp
(Amps *125%)
Recommended Minimum AC Wire Sizes
Minimum Wire Size for Specified Distance
0–50 Ft
One Way
50–100 Ft
One Way
100–200 Ft
Table 1
One Wa y
975-000-001
NOTE: These are the minimum recommended wire sizes in conduit. Installing a large number of
wires in conduit or enclosed locations may require larger wire sizes. Consult your local/national
electrical code for more information.
DC connections are made on the combiner board for models ST1500 and ST2500. The
combiner board accepts wire sizes from #614 AWG. Refer to the table below for minimum
recommended wire sizes.
DC Amps
1.01.614 AWG14 AWG14 AWG
3.04.714 AWG12 AWG10 AW G
5.07.812 AWG10 AWG6 AW G
7.010.912 AWG8 AWG6 AWG
9.014.010 AWG8 AWGNot Recommended
11.017.210 AWG6 AWGNot Recommended
NEC Amp
(Amps x 156%)
Minimu m W ire S ize fo r Spe c ifie d Dista n ce
0–25 Ft
One Way
25–50 Ft
One Way
50–100 Ft
One Way
975-000-002
Table 2
Recommended Minimum DC Wire Sizes
NOTE: These are the minimum recommended wire sizes. Installing a large number of wires in
conduit or enclosed locations may require larger wire sizes. Consult your local/national electrical
code for more information.
PV array wiring
(note polarity)
DC conduit wiring
(from solar arrays)
Figure 1
Combiner Board Indicating DC PV Array Wire Connection Points
NOTE: The National Electrical Code (NEC) places restrictions on minimum DC wire bending radius.
A #6 AWG wire is the largest that may be used on the ST1500 and ST2500 inverters.
DC connections are made at the 100 amp DC circuit breaker and the DC negative terminal
block for models ST1000 and ST2000. Refer to the table below for minimum recommended wire
sizes.
*NOTE: The National Electrical Code (NEC) places restrictions on minimum DC wire bending radius.
If the enclosures side is used for routing the wires to the DC terminals, then the wires must be bent
to make the appropriate connections. A #3 AWG wire is the largest that may be used on the ST1000
and ST2000 inverters if the side panel is used. Side knockouts are NOT provided on the unit.
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.
The main service panel must dedicate a 15 amp minimum, double pole breaker (120/240 volts
AC) to operate the ST unit.
Wire Routing:
Determine all wire routes both to and from the Sun Tie. Possible routing considerations include:
AC input wiring from the main service panel to the ST
DC input wiring from the PV array to the ST
DC ground from the PV array to an external ground rod
All wiring and installation methods should conform to applicable electrical and building codes.
Pre-plan the wire and conduit runs. The DC terminal blocks accept up to a #6 AWG wire
(ST1500 and ST2500) and #2 AWG* wire (ST1000 and ST2000); the AC circuit disconnects
accept cable sizes up to #6 AWG.
For maximum safety, run AC and DC wires/cables in (separate) conduits.
*NOTE: #2 AWG wire can only be used if the bottom knockouts are used. If punching side walls for
wire routing, the largest wire for acceptable wire bend radius is #3 AWG maximum.
WARNING: CHECK FOR EXISTING ELECTRICAL OR PLUMBING PRIOR TO DRILLING HOLES
IN THE WALLS!