Convert 12V DC to 120V AC with 3000W continuous power. Pure sine wave output with automatic transfer switch, USB ports, and comprehensive protection features.
The PowerMax PMX-3000W Pure Sine Wave Power Inverter delivers professional-grade power conversion for RVs, boats, trucks, and off-grid applications. Converting 12V DC battery power to clean 120V AC electricity, this inverter provides the same smooth, stable power as grid electricity - essential for safely operating sensitive electronics, computers, medical devices, and modern appliances.
With 3000 watts of continuous output and 6000 watts peak surge capacity, the PMX-3000W handles high-starting loads from motors, compressors, and power tools with ease. The built-in automatic transfer switch seamlessly transitions between shore power and battery power, preventing interruptions when grid power fails. Advanced digital control technology ensures reliable performance with comprehensive protection systems including low/high voltage cutoffs, overload protection, short circuit protection, and automatic thermal management.
Delivers reliable 3000W continuous output with 6000W surge capacity for starting motors and high-draw appliances
Seamlessly switches between shore power and battery power - when AC input fails, automatically transfers to inverter mode
Clean power identical to grid electricity - safely operates sensitive electronics, computers, medical equipment, and variable-speed devices
Multiple safety features including low/high voltage cutoff, overload protection, short circuit protection, and thermal shutdown
The PMX-3000W features sophisticated 110V AC pass-through technology with an integrated automatic transfer switch. When connected to shore power or a generator, the inverter passes that AC power directly to your outlets. When shore power is disconnected or fails, the unit automatically switches to inverter mode within milliseconds - drawing from your 12V battery bank to maintain uninterrupted power to your devices. This intelligent switching system eliminates the need for manual changeover and protects your electronics from power interruptions. Perfect for RV applications where you alternate between campground hookups and boondocking, or for backup power systems that need seamless transitions during utility outages.
RVs & Motorhomes: Power air conditioners, microwaves, coffee makers, TVs, and all 120V appliances when dry camping or boondocking. Automatic transfer between shore power and battery power. Marine/Boats: Run navigation equipment, refrigeration, entertainment systems, and galley appliances while at anchor or away from marina power. Work Trucks & Vans: Operate power tools, compressors, welders, and equipment at remote job sites. Perfect for contractors and service vehicles. Off-Grid Cabins: Power household appliances, computers, well pumps, and lighting systems with solar panels or generator charging. Emergency Backup: Maintain critical systems during power outages - medical equipment, refrigeration, communications, and lighting. Solar Power Systems: Essential component of off-grid solar installations, converting stored battery power to usable AC electricity.
Professional Installation Recommended • Adequate Ventilation Required: Install in well-ventilated area with clear airflow around unit. Do not block front air vents or rear exhaust ports. • Proper Wire Sizing Critical: Use appropriately sized DC cables (minimum 4 AWG recommended for 3000W). Undersized wires cause voltage drop and overheating. • Fuse Protection Mandatory: Install appropriate fuses or circuit breakers on DC positive line near battery (11 x 35A fuses included with unit). • Grounding Essential: Unit must be properly grounded to vehicle chassis or earth ground for safety. Use ground terminal on inverter. • Keep Connections Tight: Loose DC connections cause arcing, overheating, and potential fire hazards. Check all terminals regularly. • Not for Marine Use: This inverter is NOT rated for marine applications due to moisture and corrosion concerns. • Battery Capacity: Ensure adequate battery capacity - 3000W draw requires approximately 250+ amps at 12V. Use deep-cycle batteries rated for high discharge.
In The Box: • PMX-3000W-PSPT Pure Sine Wave Inverter • 11 x 35A DC Input Fuses (Installed) • 25A AC Input Fuse (Installed) • Owner's Manual with Wiring Diagrams • Warranty Documentation NOT Included (Available Separately): • 20ft Remote Control with On/Off Switch (Model PMX-001) • DC Input Cables (Must be purchased separately - use appropriate gauge for 3000W) • Battery Connection Hardware • Mounting Hardware/Brackets
Compare the PMX-3000W with other models in the PowerMax Pure Sine Wave inverter lineup to find the right power solution for your needs.
Calculate approximate runtime and battery requirements for common appliances and devices. Runtime depends on battery capacity, age, temperature, and discharge rate.
Important Notes: Runtime calculations assume 50% battery discharge (100Ah usable from 200Ah battery) and 85% inverter efficiency. Actual runtime varies based on battery type, age, temperature, and load. Starting surge not included in calculations. For extended runtime with high-draw appliances, consider multiple batteries or generator charging.
Optimal Placement: • Install in cool, dry location with good air circulation on all sides • Mount horizontally with fan axis horizontal for proper cooling • Keep minimum 6" clearance around all sides for airflow • Avoid direct sunlight and heat sources • Ideal operating temperature: 50-80°F Wiring Best Practices: • Use minimum 4 AWG copper cable for DC connections (2 AWG recommended for long runs) • Keep DC cables as short as possible to minimize voltage drop • Use insulated ring terminals with proper crimping tools • Install fuse or circuit breaker within 18" of battery positive terminal • Connect negative terminal to vehicle chassis ground or battery negative • Use wire loom or conduit to protect cables from chafing Battery Configuration: • Use deep-cycle batteries rated for high discharge (AGM or lithium preferred) • Minimum 200Ah capacity recommended for reliable 3000W operation • Multiple batteries can be paralleled for increased capacity • Keep battery bank as close to inverter as practical • Ensure batteries are fully charged before first use AC Wiring (for Pass Through): • Hire licensed electrician for hardwired AC connections • Use appropriate wire gauge for AC input (10 AWG minimum) • Install dedicated 30A circuit breaker on AC input line • Follow all local electrical codes and RV standards Testing Before Use: • Verify all connections are tight and properly insulated • Check polarity with multimeter (positive to positive, negative to negative) • Power on with no load first - green LED should illuminate • Test with small load before connecting high-draw appliances • Verify automatic transfer switch function (if using AC pass through)
Product Documentation: Download PMX Series Owner's Manual (PDF - 1000W/2000W/3000W Models) Download PMX-3000W Specification Sheet (PDF) Download PMX Series Information Sheet (PDF) Company Website: www.powermaxconverters.com PowerMax Converters 5107 Lena Road, Suite 108 Bradenton, FL 34211
A: For reliable operation at full 3000W load, you need a substantial battery bank. At maximum output, the inverter draws approximately 250+ amps from your 12V battery (3000W ÷ 12V ÷ 0.85 efficiency = ~294A). For practical use, we recommend minimum 400-600Ah of deep-cycle battery capacity (AGM or lithium). This provides 1-2 hours of full-power runtime or several hours at typical loads (500-1500W). Remember that lead-acid batteries should not be discharged below 50% capacity, so a "200Ah" battery only provides 100Ah usable. Lithium batteries can typically be discharged to 80-90%, providing more usable capacity. For extended boondocking or frequent high-draw appliance use, consider 800-1000Ah of battery capacity paired with solar panels or generator charging.
A: Yes, the PMX-3000W can start and run most 13,500 BTU RV air conditioners with proper battery capacity. Typical running power for a 13,500 BTU AC is 1500-1800 watts, well within the 3000W continuous rating. The 6000W surge capacity handles the high starting current (typically 2500-3500W for 0.3-1.0 seconds) that air conditioners require. However, you need massive battery capacity - running an AC for one hour at 1800W draws approximately 176 amps from your 12V battery. On a 400Ah battery bank (200Ah usable), you'd get about 1 hour of runtime. For extended AC use, you'll need either: (1) 800-1000Ah of battery capacity with solar charging, (2) generator to recharge batteries, or (3) combination of both. Also note that 15,000 BTU air conditioners draw 2000-2400W running and may approach the inverter's continuous limit.
A: Pure sine wave inverters like the PMX-3000W produce clean, smooth AC power identical to grid electricity, while modified sine wave inverters produce a "stepped" approximation of AC power. Pure sine wave is essential for: (1) Sensitive electronics - computers, laptops, tablets, phones charge properly without potential damage, (2) Medical equipment - CPAP machines, oxygen concentrators require pure sine wave, (3) Variable speed devices - cordless tool chargers, sewing machines, dimmer switches operate correctly, (4) Audio/video equipment - eliminates buzzing in speakers and lines in video, (5) Microwaves and refrigerators - run more efficiently and quietly, (6) Induction motors - power tools and appliances run cooler and with less wear. Modified sine wave is cheaper but can damage sensitive electronics, causes buzzing in audio equipment, reduces efficiency of motors, and won't properly charge some lithium batteries. For RV use with modern appliances and electronics, pure sine wave is worth the investment.
A: The automatic transfer switch is built into the PMX-3000W-PSPT model and requires hardwired installation by a qualified electrician. When you connect shore power or generator power to the AC input terminals on the inverter, it automatically passes that power through to the AC outlets. When shore power is disconnected or fails, the unit instantly switches to inverter mode, drawing power from your batteries. The switchover happens in milliseconds, preventing interruption to most devices. This setup is ideal for RVs because: you can leave devices plugged into the inverter's outlets, when at a campground the inverter passes shore power through and doesn't drain batteries, when boondocking the inverter automatically provides battery power, and you don't need separate shore power and inverter circuits. However, if you only want portable inverter use (plugging devices directly into the inverter), you can use it without hardwiring the AC input and skip the transfer switch functionality.
A: Wire sizing is critical for safe, efficient operation. At 3000W output, the inverter draws approximately 250-300 amps from your 12V battery (accounting for 85% efficiency). For safety and minimal voltage drop, use these wire sizes based on cable length: Under 5 feet: 4 AWG copper minimum, 2 AWG recommended; 5-10 feet: 2 AWG copper minimum, 1 AWG recommended; 10-15 feet: 1 AWG copper minimum, 1/0 AWG recommended. Never use wire smaller than 4 AWG regardless of distance - undersized wires overheat, melt insulation, and create fire hazards. Additionally: (1) Use marine-grade tinned copper wire for best corrosion resistance, (2) Ensure all connections use proper crimped ring terminals (not soldered), (3) Install inline fuse or circuit breaker within 18" of battery positive, (4) Keep cables as short as practical to minimize voltage drop, (5) Use flexible welding cable rather than solid wire for easier routing.
A: This is voltage drop under load - a common issue with inadequate battery capacity or undersized wiring. Your battery may show 12V or higher when sitting idle, but under the heavy load of the inverter, the voltage quickly drops below the 10.5V low-voltage cutoff. Common causes: (1) Weak/old batteries: Batteries lose capacity with age and can't maintain voltage under high current draw. Test battery health with a load tester. (2) Insufficient battery capacity: A single 100Ah battery can't sustain 250+ amps for long. Add more batteries in parallel. (3) Undersized wiring: Thin wires cause significant voltage drop. Upgrade to 2 AWG or larger cables. (4) Poor connections: Loose or corroded terminals create resistance. Clean and tighten all connections. (5) Long cable runs: Voltage drop increases with distance. Shorten cables or increase wire gauge. The inverter's low-voltage protection is working correctly - it shuts down to prevent battery damage. The solution is addressing the underlying power supply issue, not bypassing the protection.