Victron Energy SmartSolar MPPT RS 450/100-MC4100A 48V isolated MPPT solar charge controller, 450V PV, 2 trackers

Overview

The SmartSolar MPPT RS 450/100-MC4 charges a 48V battery with up to 100A, or 5.8kW at 57.6V, from two independent trackers with MC4 connectors. Each tracker accepts strings up to 450V open-circuit voltage and delivers up to 4000W, so two strings oriented differently, for example east and west, can be handled separately. PV and battery are galvanically isolated. At 7.9kg and 313×440×126mm it suits off-grid homes, workshops and ESS installations with 48V batteries; Victron asks for at least 200Ah lead-acid or 50Ah lithium and a 125–150A DC fuse.

• 48V battery charging at 100A or 200A
• 450V max. PV voltage, 65–450V MPPT range
• Two or four independent MPPT trackers
• Full galvanic isolation between PV and battery
• PV insulation resistance monitoring
• Up to 25 units synchronised via VE.Can

How it works

The MPPT RS is a high-voltage solar charge controller for 48V battery banks. It accepts PV strings up to 450V, starts at 120V and tracks between 65V and 450V, so long strings can be run with thin cables over a distance. Each tracker takes up to 16A of operating current and 4000W of charging power. The 450/100 has two trackers (5.76kW total), the 450/200 has four (11.52kW). Charging is adaptive multi-stage, with absorption 57.6V and float 55.2V by default and a programmable range of 36–60V.

The PV side is fully galvanically isolated from the battery terminals, so a fault on the array cannot carry PV voltage to the battery side. The controller continuously measures the insulation resistance between PV+ and PV- and earth; below 100kΩ it reports an error, which a GX device can turn into an audible alarm or an e-mail, while charging continues.

Installation and compatibility

Mount the unit upright on a non-flammable wall with 30cm clear above and below, out of direct sunlight and away from dust, soot or salt. The chassis must be earthed and the PV conductors must stay isolated from ground. Each tracker needs its own array: one array must not be split over several inputs, and optimisers cannot be used. The open-circuit voltage of the array must stay below eight times the battery float voltage, for example 432V at a 54V float.

Victron's minimum requirements are a 200Ah lead-acid or 50Ah lithium battery with a 125–150A fuse for the 450/100, and 400Ah lead-acid or 100Ah lithium with a 250A fuse for the 450/200. Battery cables must be at least 35mm² (450/100) or 70mm² (450/200) for runs up to 2m. Connect the battery first, then control and communication cables, then the PV. Lithium batteries can be managed through the remote terminals in 2-wire BMS mode, for example with a smallBMS.

Monitoring and settings

A built-in display shows battery and controller values, and Bluetooth gives access to all settings, firmware updates and a 30-day history per tracker in the VictronConnect app. The unit is not compatible with VE.Smart Networks. A VE.Direct port and two VE.Can ports connect a GX device for VRM monitoring and remote firmware updates, and VE.Can synchronises up to 25 controllers with identical settings.

Battery voltage sense wires, a temperature sensor (included), a programmable relay for alarm or generator start, two analogue/digital inputs and remote on/off are on the user I/O connector. The controller can also be part of a Victron Energy Storage System together with an inverter/charger and a GX device.

Questions and answers