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Inverter Selection Guide

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This article is prepared to help you choose amongst the most popular off-grid or grid optional inverters which we offer.  Please note we continuously improve our products and introduce new functionality so the table below may not necessarily reflect the most updated features. If you have any questions please feel free to email us or refer to the specific product page for the most up-to-date information.

 PIP-HSPIP-MS/MSXPIP-MSDPIP-MSTPIP-HSE/MSEHYBRID
Phase TypeSingle*Single*Single*Single*SingleSingle / Three
Application TypeGrid-OptionalGrid-OptionalGrid-OptionalGrid-OptionalGrid-OptionalHybrid
WaveformPure Sine WavePure Sine WavePure Sine WavePure Sine WavePure Sine WavePure Sine Wave
Continuous Power800W - 4.0KW800W - 4.0KW1.2KW - 4.0KW4.0KW2.4KW, 4.0KW3.0KW, 10KW
ParallelYes*Yes*Yes*Yes*NoYes
System Voltage12V, 24V, 48V12V, 24V, 48V12V, 24V, 48V48V24V, 48V48V Only
Output Voltage230V230V230V230V230V230 / 400Vac
Output Frequency50/60Hz50/60Hz 50/60Hz50/60Hz50/60Hz50/60Hz
Peak Efficiency>95%>93%>93%>93%>93%>96%
Battery ChargerUp to 60AUp to 60AUp to 60AUp to 60A30A, 60A25-200A Max
Solar Charger50A PWMup to 80A MPPTUp to 120A MPPTUp to 180A MPPT50A PWM, 40A-60A MPPTMPPT
Standby ModeYesYesYesYesYesYes
AccessoriesRemote Display, SNMP Web BoxRemote Display, SNMP Web BoxSNMP Card, SNMP Web BoxSNMP Web BoxNoModbus, Energy Meter
Genset StarterYesYesYesYesNoN/A
MonitoringYesYesYesYesYesYes
CertificationCECECECECECE, VDE4105 / 0126-1-1, AS4777

Common Terminology in Inverter Selection

Phase type.  All inverters we carry, unless otherwise stated, are all for 220-240v power standards.  There are two main phase types – single phase vs. three phase.  Single phase typically consists of a single hot wire and a single neutral wire and nominal voltage is 230V (220-240V).   Three phases are usually made up of three hot wires with a single neutral wire.  In a three phase setting, each phase to neutral is still 230V, however phase to phase is 400V.
*selective PIP-HS/MS/MSD/MST models support parallel operation for Single Phase or Three Phase applications.

Application Type.  All inverters we have can operate in the “grid-optional” setting (e.g. off-grid, or grid-connected but only to draw power).  An inverter simply inverts battery power (DC) to alternate current (AC).  Inverter-chargers such as PIP-HS / PIP-MS series include AC input terminals that allow utility (or generators) connection to power load or charge batteries.  AC input connection is not mandatory, and therefore these types of inverters are also defined as “grid-optional”. “Hybrid” inverters are defined as devices that can both feed power back to utility and at the same time use battery power as backup.  Hybrid inverters are usually most expensive and also require compliance to a specific grid standard before it can be legally used to feed-in power back to grid.

Waveform.  This refers to the output waveform type of the inverter.  Inverters nowadays typically come in two main types: Modified Sine Wave vs. Pure Sine Wave.  Pure Sine Wave output inverters have lower total harmonic distortion and generally can power all types of load without issue. They are by far much more compatible with most load than Modified Sine Wave ones, but at the same time, also more expensive.

Continuous Power.  Arguably the most important attribute of an inverter.  This rating defines how much power output can be provided continuously to load.  When sizing an inverter with load, this should be the first thing to check.  Always size inverters conservatively.  If you expect to run a certain watt of load, always multiply this by 1.2 or 1.25, which not only will work as a buffer in case there is any under-estimation, but this will also be a more proper and efficient use of inverters as they are often running most efficiently at about 70 to 80% load.

Parallel.  This refers to an inverter’s ability to connect in multiple numbers in order to increase the overall power output to load.  Only 4-5KVA, 48V models of PIP-HS, PIP-MS, PIP-MSD, PIP-MST series support parallel operation (3248HS, 4048HS, 3248MS, 4048MS).  Maximum number of parallel units is 6, or max 24kw if each inverter is 4kw.  In a parallel system, all units must be the same model.  Parallel operation in HS/MS series requires the use of parallel kit on each and every unit in parallel.  When stacked in parallel, they can be configured as single phase or three phase systems.
*Parallel kits are required.

System Voltage.  Also known as the DC nominal voltage rating of an inverter, this suggests the battery bank voltage at which must be configured in order to properly power the inverter. Most common off-grid system voltages are 12v, 24v and 48v.  While not necessarily applicable to all inverters, most small output inverters are designed in 12v, and as output increases, the demand for system voltage is raised to 24v or 48v in order to maintain a good design efficiency.  Higher nominal battery bank voltage ensures lower current in the battery cables (referring to the Power Law) which translates to less energy loss for the same gauge cables.

Output Voltage.  This is the NOMINAL output voltage of an inverter.  Output voltage of an inverter by world standards fall under 2 main types: 110-120V type or the 220-240V type.   All our inverters, unless otherwise stated, are designed for 220-240V standards only.  Please check with your local mains power standard before buying an inverter, as otherwise the use of a wrong output voltage inverter may seriously damage your load (and the inverter itself).

Output Frequency.  Load frequencies come in two standards: 50Hz or 60Hz  Most countries using 220-240V follow the 50Hz standard while the 110-120V ones use the 60Hz, though in some cases there may be exceptions.  It is important to know the types of frequency your AC load runs in and ensure the inverter is properly programmed to match this frequency.   Most of our inverters can be programmed to work in either with 50Hz or 60Hz.

Peak Efficiency.  Inverter efficiency usually refers to the conversion efficiency of an inverter from DC source power such as battery or solar into AC power.  The higher the efficiency means the lower the power was wasted during the conversion.  Efficiency under “line mode” (or AC bypass mode) is typically higher than under inverter mode because while under line mode, the inverter is only bypassing the power coming from AC input source directly to load, and therefore there’s little or no conversion required.

Battery Charger. Inverter-chargers come with an internal battery charger which allows unit to use AC power sources such as utility or generators to charge batteries.  This feature eliminates the need of having an external battery charger, and is critical during times when solar power is unavailable.  Built-in battery chargers are usually rated in DC current (amps) based on the system voltage of the inverter.

Solar Charger.  Solar chargers are also battery chargers, except instead of using AC source powers, these draw power from solar panels.  This feature is very useful as it negates the need of having to set up external solar chargers.  Solar chargers come in two main categories: MPPT vs PWM.   MPPT type chargers allow the use the higher voltage panels on lower voltage systems, as they can convert the high voltage input into an elevated output current so little power is wasted.  Conversion efficiency depends on the level of input voltage – generally speaking higher input voltage will have lower efficiency.  Inverter-chargers with MPPT type chargers will also be more expensive than ones with built-in PWM type.

Standby Mode.  Inverters with standby mode will draw far less power than sitting idly when there is no load.  The main purpose of this feature is to help conserve battery power when inverters are not doing any real work, e.g. no load or very low load.  When this feature is enabled, once load level falls below a certain point, the inverter will enter standby mode and stop producing any power.  If load level returns to above the threshold, the unit will resume normal operation.

Accessories.  Remote LCD display (15m length wire) is available for our PIP-HS and PIP-MS/MSX series at this time.  SNMP web monitoring is also available through SNMP card or SNMP Web Box which can be supplied separately for use on all of our off-grid/grid optional family inverters, except PIP-HSE/MSE.

Genset Starter. This feature is only available on our PIP-HS/MS/MSX/MSD/MST series.  The genset starter is simply a two-wire connection dry contact which can be wired to a generator that support remote start-up functionality.  The dry contact is activated when inverters running in DC priority mode experience low battery voltage, and it will send a signal to turn on the generator in order to act as backup to load.   By definition, the dry contact does not carry any live voltage and only send signals.

Monitoring.  Inverters with monitoring features provide a graphical interface on PC through USB or RS232 and display important system parameters in an easy-to-read format.  The monitoring software provided on PIP-HS, PIP-MS/MSX/MSD/MST, and the Hybrid series also offer data logging functionality and advanced parameter programming so that users can adjust the inverter to suit their application.  WatchPower (for PIP-HS/MS/MSX/MSD/MST) and SolarPower software (for Hybrid) are now available for use on Windows, Mac, and Linux.

Certification.  All our inverters are CE compliant so safe for use in EU and any other countries that recognize this standard.  For hybrid inverters they come with additional certifications (VDE4105, VDE0126-1-1, AS4777) as these are specific regional standards required for grid-feedback.  VDE standards are widely accepted in Germany and many European countries.  AS standards are recognized in Australia and New Zealand.