Samlexpower PST-300-12 User manual

Please read this
manual BEFORE
installing your
inverter
Owner's
Manual
DC-AC Power
Inverter
Pure Sine Wave
PST-300-12
PST-300-24

2 | SAMLEX AMERICA INC.
OWNER'S MANUAL | Index
SECTION 1 Safety Instructions ........................................3
SECTION 2 General Information .....................................9
SECTION 3
Limiting Electromagnetic Interference (EMI) ....................... 16
SECTION 4
Powering Direct / Embedded Switch Mode
Power Supplies (SMPS) ....................................................... 17
SECTION 5 Principle of Operation ............................... 19
SECTION 6 Layout........................................................ 20
SECTION 7
General Information - Battery Related................................. 21
SECTION 8 Installation ................................................. 35
SECTION 9 Operation ...................................................53
SECTION 10 Protections ............................................. 55
SECTION 11 Troubleshooting Guide ........................... 59
SECTION 12 Specications ......................................... 62
SECTION 13 Warranty ..................................................64
Disclaimer of Liability
UNLESS SPECIFICALLY AGREED TO IN WRITING, SAMLEX AMERICA INC.:
1. MAKES NO WARRANTY AS TO THE ACCURACY, SUFFICIENCY OR SUITABILITY OF ANY TECHNICAL OR OTHER INFORMATION
PROVIDED IN ITS MANUALS OR OTHER DOCUMENTATION.
2. ASSUMES NO RESPONSIBILITY OR LIABILITY FOR LOSSES, DAMAGES, COSTS OR EXPENSES, WHETHER SPECIAL, DIRECT, INDI-
RECT, CONSEQUENTIAL OR INCIDENTAL, WHICH MIGHT ARISE OUT OF THE USE OF SUCH INFORMATION. THE USE OF ANY
SUCH INFORMATION WILL BE ENTIRELY AT THE USERS RISK.
Samlex America reserves the right to revise this document and to periodically make changes to the content
hereof without obligation or organization of such revisions or changes.
Copyright Notice/Notice of Copyright
Copyright © 2021 by Samlex America Inc. All rights reserved. Permission to copy, distribute and /or modify this
document is prohibited without express written permission by Samlex America Inc.

2 | SAMLEX AMERICA INC. SAMLEX AMERICA INC. | 3
SECTION 1 | Safety Instructions
1.1 SAFETY SYMBOLS
The following safety symbols will be used in this manual to highlight safety
and information:
WARNING!
Indicates possibility of physical harm to the user in case of non-compliance.
!
CAUTION!
Indicates possibility of damage to the equipment in case of non-compliance.
i
INFO
Indicates useful supplemental information.
Please read these instructions before installing or operating the unit to prevent personal
injury or damage to the unit.
1.2 SAFETY INSTRUCTIONS - GENERAL
1.2.1 Installation and wiring compliance
• Installation and wiring must comply with the Local and National Electrical Codes and
must be done by a certied electrician.
1.2.2 Preventing electrical shock
• Always connect the grounding connection on the unit to the appropriate grounding
system.
• Disassembly / repair should be carried out by qualied personnel only.
• Disconnect all AC and DC side connections before working on any circuits associated
with the unit. Turning the ON/OFF switch on the unit to OFF position may not entirely
remove dangerous voltages.
• Be careful when touching bare terminals of capacitors. Capacitors may retain high le-
thal voltages even after the power has been removed. Discharge the capacitors before
working on the circuits.
1.2.3 Installation environment
• The inverter should be installed indoor only in a well ventilated, cool, dry
environment.
• Do not expose to moisture, rain, snow or liquids of any type.
• To reduce the risk of overheating and re, do not obstruct the suction and discharge
openings of the cooling fan.
• To ensure proper ventilation, do not install in a low clearance compartment.
1.2.4 Preventing re and explosion hazards
• Working with the unit may produce arcs or sparks. Thus, the unit should not be used
in areas where there are ammable materials or gases requiring ignition protected

4 | SAMLEX AMERICA INC.
SECTION 1 | Safety Instructions
equipment. These areas may include spaces containing gasoline-powered machinery,
fuel tanks, and battery compartments.
1.2.5 Precautions when working with batteries
• Batteries contain very corrosive diluted Sulphuric Acid as electrolyte. Precautions
should be taken to prevent contact with skin, eyes or clothing.
• Batteries generate Hydrogen and Oxygen during charging resulting in evolution of
explosive gas mixture. Care should be taken to ventilate the battery area and follow
the battery manufacturer’s recommendations.
• Never smoke or allow a spark or ame near the batteries.
• Use caution to reduce the risk of dropping a metal tool on the battery. It could spark
or short circuit the battery or other electrical parts and could cause an explosion.
• Remove metal items like rings, bracelets and watches when working with batteries.
The batteries can produce a short circuit current high enough to weld a ring or the
like to metal and thus, cause a severe burn.
• If you need to remove a battery, always remove the ground terminal from the battery
rst. Make sure that all the accessories are off so that you do not cause a spark.
1.3 SAFETY INSTRUCTIONS - INVERTER RELATED
1.3.1 Preventing Paralleling of the AC Output
The AC output of the unit should never be connected directly to an Electrical Breaker
Panel / Load Centre which is also fed from the utility power / generator. Such a direct
connection may result in parallel operation of the different power sources and AC
power from the utility / generator will be fed back into the unit which will instantly
damage the output section of the unit and may also pose a re and safety hazard. If an
Electrical Breaker Panel / Load Center is fed from this unit and this panel is also required
to be fed from additional alternate AC sources, the AC power from all the AC sources
(like the utility / generator / this inverter) should rst be fed to an Automatic / Manual Se-
lector Switch and the output of the Selector Switch should be connected to the Electrical
Breaker Panel / Load Center. Samlex America, Inc. Automatic Transter Switch model No.
STS-30 is recommended for this application.
!
CAUTION!
To prevent possibility of paralleling and severe damage to the unit, never use a
simple jumper cable with a male plug on both ends to connect the AC output
of the unit to a handy wall receptacle in the home / RV.
!
ATTENTION!
Pour éviter toute possibilité de mise en parallèle et de graves dommages à
l'appareil, n'utilisez jamais un simple câble de raccordement muni d'une che
mâle aux deux extrémités pour connecter la sortie CA de l'appareil à une prise
murale pratique dans le logement / véhicule de loisir.

4 | SAMLEX AMERICA INC. SAMLEX AMERICA INC. | 5
SECTION 1 | Safety Instructions
1.3.2 Preventing DC Input Over Voltage
It is to be ensured that the DC input voltage does not exceed 16.5 VDC for PST-300-12 or
33.0 VDC for PST-300-24 to prevent permanent damage to the unit. Please observe the
following precautions:
• Ensure that the maximum charging voltage of the external battery charger / alterna-
tor / solar charge controller does not exceed 16.5 VDC for PST-300-12 or 33.0 for PST-
300-24.
• Do not connect this unit to a battery system with a voltage higher than the rated
nominal battery input voltage of the unit.
• When using Diversion Charge Control Mode in a Charge Controller, the solar/ wind/
hydro source is directly connected to the battery bank. In this case, the Controller will
divert excess current to an external load. As the battery charges, the diversion duty
cycle will increase. When the battery is fully charged, all the source energy will ow
into the diversion load if there are no other loads. The Charge Controller will discon-
nect the diversion load if the current rating of the Controller is exceeded. Disconnec-
tion of the diversion load may damage the battery as well as the inverter or other DC
loads connected to the battery due to high voltages generated during conditions of
high winds (for wind generators), high water ow rates (for hydro generators). It is,
therefore, to be ensured that the diversion load is sized correctly to prevent the above
over voltage conditions.
• Do not use solar panel/array to directly charge the battery bank connected to the
inverter. Use appropriate Charge Controller between the solar panel/array and the
battery bank. Using solar panel/array to directly charge the battery will lead to over
voltage shutdown of the inverter and the possible damage due to battery voltage ris-
ing close to the level of the open circuit voltage of the solar panel(s) when the battery
is fully charged and is in Float stage (under this condition, the battery will be drawing
very low trickle charge current & the voltage of the unregulated solar panel/array will
rise close to its Open Circuit Voltage).
1.3.3 Preventing Reverse Polarity on the Input Side
When making battery connections on the input side, make sure that the polarity of bat-
tery connections is correct (Connect the Positive of the battery to the Positive terminal of
the unit and the Negative of the battery to the Negative terminal of the unit). If the input
is connected in reverse polarity, DC fuse(s) inside the inverter will blow and may also
cause permanent damage to the inverter.
!
CAUTION!
Damage caused by reverse polarity is not covered by warranty.
!
ATTENTION!
Les dommages causés par l'inversion de polarité ne sont pas couverts par la garantie.