Victron Energy MultiPlus-II Inverter/Charger, 12V, 3000VA, 120A Charger, 120V AC, 50A Transfer Switch

Overview

The Victron Energy PMP122305120 is a MultiPlus-II 12/3000/120-50 120V inverter/charger for 12V battery systems that combines a 120V AC inverter, battery charger, and automatic transfer switch in one unit. It supports a 9.5 to 17V DC input range, delivers 3000VA inverter capacity, and charges at up to 120A, making it a practical power hub for boats with larger house banks, shore power, generator input, and AC loads on board.

This model is suited to marine electrical systems where the boat needs stable AC power underway, at anchor, or during dockside use. The 50A transfer switch manages AC input, while PowerControl and PowerAssist help limit shore or generator overload by reducing charge current or adding battery power during short peaks in demand.

The unit has two AC outputs. The main output can take over in less than 20 milliseconds when shore or generator power drops out, which helps keep sensitive electronics running through a power changeover. The second AC output is active only when AC input is available, useful for loads that should not drain the battery bank when the vessel is away from shore power.

Key features

• 12V inverter/charger with 3000VA output capacity and 120V AC output at 60 Hz for onboard AC systems.
• Up to 120A battery charging for 12V house banks when connected to shore power or a generator.
• 50A transfer switch with a 90 to 140V AC input range for typical 120V dockside and generator installations.
• PowerAssist can add battery power when shore or generator input is limited, helping prevent nuisance overloads during short demand peaks.
• UPS-style transfer in less than 20 milliseconds helps maintain power to computers, navigation support electronics, and other sensitive AC loads.
• Two AC outputs allow critical loads to remain on inverter power while selected non-critical loads operate only when AC input is present.
• VE.Bus communication supports system integration, remote monitoring, parallel operation, split-phase setups, and three-phase configurations when properly configured.
• Compatible with GX monitoring equipment and VRM remote access when added to a larger Victron system.
• Steel enclosure with IP22 protection rating for installation in a dry, protected electrical space on board.
• UL458 listing supports use in mobile and marine-style AC power systems where that listing is required.

Installation and setup

This inverter/charger should be mounted in a protected electrical compartment with ventilation and access for service. Its IP22 rating means it belongs away from bilge water, washdown spray, cockpit splash zones, and direct weather exposure. Fan-assisted cooling and the 42 lb weight also make solid mounting and clear airflow important.

Battery connections use M8 bolts, and the 120V AC connection is sized for 13 mm² or 6 AWG conductors. The installation should be planned around cable length, battery bank capacity, overcurrent protection, grounding, and the vessel AC distribution layout.

Electrical and system integration

For a boat with shore power and generator input, the MultiPlus-II can manage charging while keeping AC loads supplied through the main output. The PowerControl setting lets the system respect a limited pedestal or generator capacity, which is useful at marinas with smaller shore service or when running from a compact genset.

VE.Bus support allows the unit to become part of a broader Victron power system. With a GX device, owners can view system status locally or remotely, adjust settings, and monitor battery and AC power behavior through the Victron monitoring ecosystem. An optional external AC current sensor can be used for extended current sensing and energy management in supported installations.

Use cases on board

This model fits boats that need a single inverter/charger to handle larger AC loads, charge a 12V battery bank, and manage changeover between shore power, generator power, and inverter power. It is a strong match for cruising boats, fishing boats, and liveaboard systems where AC power reliability and battery charging control matter every day.

Because it includes a second AC output, it can help separate loads that should remain available from loads that should only run when external AC power is present, such as a water heater or other equipment that should not pull down the battery bank at anchor.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Orders of $100 or more qualify for free shipping when eligible. For orders under $100, shipping costs are calculated at checkout based on destination, package weight, and selected service. International shipping is available for eligible products, and certain items may require additional handling, warehouse transfers, or may ship directly from the manufacturer, which can affect processing time.

Deliveries are handled by preferred carriers such as USPS, UPS, FedEx, DHL, and others depending on your location and selected service. Estimated delivery times are displayed at checkout and may vary due to customs processing, carrier delays, weather, postal disruptions, or other circumstances beyond our control. Once your order ships, you'll receive a confirmation email with tracking information. Tracking may take up to 24 hours to update on the carrier's website and is also available through your account when applicable.

We ship throughout the United States and to most international destinations for products eligible for international shipping. International orders may be subject to customs duties, taxes, brokerage charges, or other import fees, which are the customer's responsibility and are not included in the product or shipping price. PO Boxes are accepted only when shipping through USPS, and not all packages qualify for this option. If your order does not arrive within the estimated delivery window, please contact us at info@apollolighting.com or +1 (954) 375-0100 so we can assist with locating your package.

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Returns may be requested within 30 days of receiving your order. Items must be unused, uninstalled, unaltered, and returned in their original packaging with all tags, packing materials, blank warranty cards, manuals, instructions, accessories, and included items. Certain products, including installed or used electronics, electrical components, lighting, consumables, custom or special-order items, cut-to-length products, safety equipment, and merchandise exposed to water or marine conditions, may not be eligible for return.

To request a return, sign in to your account and select the applicable order and items, and submit your request for review. Eligible unfulfilled items may also be submitted for cancellation within 1 hour of placing the order. Returns or cancellations are not considered approved until you receive confirmation from Apollo Lighting. Please do not ship or drop off merchandise before receiving return approval and instructions.

Customers are responsible for arranging and paying for return shipping unless the return is due to an error by Apollo Lighting or the item is verified as defective, damaged, or incorrect. Missing, damaged, defective, or incorrect items must be reported within 2 business days of delivery, and photos or other documentation may be required for review. If the issue is verified, Apollo Lighting may provide or reimburse return shipping and issue a replacement or refund depending on the circumstances. International customers are responsible for return shipping, duties, taxes, customs charges, brokerage fees, and other costs associated with an international return.

After your return is received and inspected, approved refunds are issued to the original payment method and may take 5-7 business days to appear after processing. Original shipping and handling charges are nonrefundable, and the value of any included free items that are not returned may be deducted from the refund. Apollo Lighting does not charge a standard restocking fee on eligible returns. Returns that are incomplete, damaged, installed, used, altered, improperly packaged, or otherwise do not meet the eligibility requirements may be refused. We recommend using a trackable and appropriately insured shipping service for all customer-arranged returns.

For assistance, contact info@apollolighting.com or call +1 (954) 375-0100.

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Many products sold by Apollo Lighting include a manufacturer's warranty covering defects in materials or workmanship. Warranty terms vary by brand, product category, and model, so eligibility, coverage duration, exclusions, and available remedies are determined by the applicable manufacturer. We recommend reviewing the warranty information provided with your product before installation or use, especially for marine electronics, navigation equipment, lighting, electrical systems, pumps, safety equipment, and other specialized marine products.

If you need warranty service, the claim must follow the process established by the manufacturer, authorized service center, or designated warranty provider. You may be asked for proof of purchase, a serial number, product registration, photos, maintenance or installation records, or other documentation. Apollo Lighting does not determine or modify a manufacturer's warranty coverage or final claim decision, but we are happy to help provide purchase information and direct you to the appropriate manufacturer or warranty resource.

Keep your receipt, product documentation, serial number information, and original packaging when practical. Damage caused by normal wear, misuse, improper installation, insufficient maintenance, corrosion, impact, unauthorized modifications, electrical issues, or operation outside the manufacturer's specifications may not be covered. Warranty claims are separate from standard returns, so a product that has been installed, used, or exposed to marine conditions may no longer qualify for return while still remaining eligible for evaluation under the manufacturer's applicable warranty.

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