Victron SmartSolar MPPT 75/15 vs 100/30

Choose the Victron SmartSolar MPPT 75/15 for a 12V or 24V battery when its 15A charging limit and 220W/440W nominal PV ratings cover your plan. Choose the 100/30 for 30A charging, 440W/880W nominal PV, or a higher PV-voltage allowance, after checking its separate input limits. Neither supports a 48V battery bank.

Quick picks: choose by the requirement that changes

Compare specifications and all conditions

Smaller array; charging demand within the smaller model’s rating

Pick

75/15

Why

220W at 12V or 440W at 24V; 15A battery charging

More charging current or nominal PV capacity

Pick

100/30

Why

440W at 12V or 880W at 24V; 30A battery charging

Physical load-output terminals needed

Pick

75/15, within its load rating

Why

15A physical load output; the 100/30 has virtual load control instead

48V battery or cold array Voc above 100V

Pick

Neither

Why

Revisit the controller or array design

Full comparison table ↔

Swipe to compare. Row labels stay visible.

Your requirement	Pick	Why
Smaller array; charging demand within the smaller model’s rating	75/15	220W at 12V or 440W at 24V; 15A battery charging
More charging current or nominal PV capacity	100/30	440W at 12V or 880W at 24V; 30A battery charging
Physical load-output terminals needed	75/15, within its load rating	15A physical load output; the 100/30 has virtual load control instead
48V battery or cold array Voc above 100V	Neither	Revisit the controller or array design

Your requirement	Pick	Why
Smaller array; charging demand within the smaller model’s rating	75/15	220W at 12V or 440W at 24V; 15A battery charging
More charging current or nominal PV capacity	100/30	440W at 12V or 880W at 24V; 30A battery charging
Physical load-output terminals needed	75/15, within its load rating	15A physical load output; the 100/30 has virtual load control instead
48V battery or cold array Voc above 100V	Neither	Revisit the controller or array design

The model name describes maximum PV voltage / maximum battery charge current. The 30A in 100/30 is battery-side charging current; its separate maximum PV short-circuit current is 35A. Use the general solar charge controller guide for MPPT-versus-PWM background; this comparison is about choosing between these exact SmartSolar models.

• 15A75/15 maximum battery charge current
• 30A100/30 maximum battery charge current

Published limits and your requirements worksheet

These figures come from Victron’s model-specific 75/15 table and 100/30 table. Record the proposed system in the last column before ordering.

The PV wattage entries are nominal sizing ratings, not guaranteed charging output. Both controllers limit input power when more PV wattage is connected, but that does not relax the voltage or Isc limits. Both are fully rated up to 40°C ambient; output is reduced above that temperature.

Choose the 75/15 for an array that already fits

The 75/15 is our smaller-system pick when its battery-current, nominal-wattage and PV input limits all fit, including planned expansion. It also preserves a physical load output with configurable low-voltage disconnection, useful when the system needs that function. That output is limited to 15A; a high-current inverter can exceed its capacity.

You retain built-in Bluetooth, VictronConnect settings and firmware updates, plus the VE.Direct port. We would keep the smaller controller when the requirements fit and the larger model would add unused charging capacity.

View the SmartSolar 75/15 on Victron’s site

Choose the 100/30 when a documented limit requires it

The 100/30 is our pick for greater charging capacity: its nominal PV rating and battery-current allowance are double the 75/15’s at the same battery voltage. It also raises the PV Voc ceiling from 75V to 100V and the Isc allowance from 15A to 35A. Those are independent reasons to upgrade; needing more voltage headroom does not necessarily mean needing more charging current.

The tradeoff is the absence of physical load-output terminals; virtual control needs the corresponding external equipment. Its maximum charge-current setting can be reduced for a battery that needs less current. Do not assume that a battery can accept the controller’s full output: have its maker’s charging limits checked against the selected setting.

View the SmartSolar 100/30 on Victron’s site

Look-alikes and conflicting family-page wording

SmartSolar and BlueSolar are different versions: SmartSolar has built-in Bluetooth; BlueSolar needs an optional dongle for Bluetooth. The SmartSolar 100/15 is another possible specification match when only the voltage ceiling needs to rise: it retains 15A charging and 220W/440W nominal PV ratings, with a 100V PV ceiling. The 100/50 is also a different controller, rated for 50A charging; do not read its adjacent specification column as the 100/30’s.

Victron’s small-controller family page says “12/24/48 Volt,” while the exact 75/15 table specifies 12V or 24V. The family marketing also mentions a VE.Can connection; the exact manuals for these picks specify VE.Direct. Use the model-specific limits and ports when buying accessories.

Check panel watts, cold voltage and current separately

Start with the battery-voltage row: the same 440W nominal array matches the 75/15’s 24V rating or the 100/30’s 12V rating. Moving to the larger controller can avoid power limiting, but cannot make an incompatible battery voltage work.

For the panel worksheet, collect the exact model, rated power, Voc, maximum-power voltage (Vmp), Isc and Voc temperature coefficient from its datasheet. Ask the system designer to check the proposed array arrangement and lowest design temperature, including future panels. Victron warns that Voc rises below 25°C and that the panel’s temperature coefficient must be included. Also check the lower PV operating requirement in hot weather; passing the cold-voltage ceiling alone does not establish a complete match.

Compare array short-circuit current, rather than panel operating current, with the Isc row. Victron’s datasheet warns that excess array Isc can damage the controller. Victron’s manual qualifies that warning by specifying reverse-polarity connection of the PV array. Have the designer apply the panel manual’s design factors and site requirements; the examples below use nameplate Isc only.

Worked examples: a smaller pick, an upgrade and neither

Use an identifiable panel as the starting point: Victron’s BlueSolar datasheet lists the SPM041501200 at 150W, Vmp 18.2V, Voc 22.3V and Isc 8.69A. Its Voc temperature coefficient is −0.35%/°C, and the STC reference temperature is 25°C. These are calculations for proposed arrays of identical panels, assuming a minimum panel temperature of −10°C; they are not measured output or a local climate recommendation.

For these panels below the reference temperature, calculate cold array Voc = panel count × 22.3V × [1 + (0.35 ÷ 100) × (25 − minimum panel temperature in °C)]. The proposed series strings below assume identical panels: their Voc values add, while each string’s nameplate Isc remains 8.69A. For four panels at the assumed minimum, 4 × 22.3V × [1 + (0.35 ÷ 100) × (25 + 10)] exceeds 100V, ruling out both controllers.

The candidate picks still require battery-profile approval and a check of startup and hot-weather operating voltage. Use Victron’s MPPT calculator with your actual panel data and have the proposed design reviewed before ordering.

Battery profiles and winter lithium charging

Victron lists lithium, AGM, gel and flooded compatibility, and both manuals describe adjustable charge algorithms and current limits. Match the battery maker’s charge-voltage, current and temperature requirements; the lithium preset does not support equalization.

Cold-charge protection needs a separate check. The 75/15 and 100/30 settings manuals say low-temperature cutoff is disabled by default and works only when a VE.Smart network supplies a battery-temperature reading from compatible external sensing hardware. The internal controller sensor alone does not satisfy that requirement. For battery selection, continue to our winter RV lithium battery guide.

Monitoring and the accessories to account for

The 75/15 and 100/30 manuals document local Bluetooth monitoring, configuration and firmware updates through VictronConnect. Their manuals list an optional VE.Direct-to-USB interface for USB access, and optional GX or GlobalLink 520 hardware for internet/LAN access through VRM. The optional MPPT Control display uses VE.Direct; its required VE.Direct cable is not included with that display.

For external battery-temperature and voltage sensing, the manuals document Smart Battery Sense, or a compatible BMV-712 Smart/SmartShunt monitor equipped with the appropriate temperature sensor. Choose accessories for the required function, rather than assuming that Bluetooth includes a display, internet access or battery-temperature measurement.

• Yes: Local phone monitoring: built-in Bluetooth
• Partly: Fixed display: optional MPPT Control and a separate VE.Direct cable
• Partly: Internet monitoring: optional GX or GlobalLink communication hardware

How we choose

We compared official Victron product pages, exact-model specification tables, manuals and panel data. The recommendations are research judgments, without physical product testing; array examples are stated calculations with explicit temperature assumptions. A qualified installer should validate the electrical design and handle installation.

Verdict

Choose the 75/15 when the complete array and battery requirements fit its limits, especially if a physical load output matters. Choose the 100/30 when its extra charging capacity or PV headroom solves a documented requirement. For a 48V battery or an array that exceeds the larger model’s cold-voltage ceiling, choose neither and revisit the design.