The Renogy 40D1S and the Renogy Pro IP67 are among the best DC-DC MPPT battery chargers available for vans, motorhomes, and boats. However, they have been designed for different charging needs and applications.
If you need more power and a more sophisticated charging solution, the Pro IP67 is the best choice. The 40D1S, on the other hand, is ideal if you're working within a tighter budget and only require reliable basic features.
In this quick guide, we'll walk you through the key differences and similarities between these two Renogy DC-DC chargers. For simplicity, we may refer to the 40D1S as the "basic" charger throughout the article.
Renogy 40D1S vs Pro IP67: Overview and Key Specifications
The Renogy 40A DC-DC Battery Charger with MPPT (40D1S) is designed for caravanners, RVers, van-lifers, and boat owners on a tight budget who need only a DC-DC battery charger with the essential features. The unit adopts a two-way adaptive charging logic that charges your leisure battery from either the alternator (starter battery) or solar panels, and it can deliver up to 616 watts at 40 amps.
Meanwhile, the Renogy Pro IP67 50A DC-DC Battery Charger with MPPT features a more advanced design, beginning with a three-way adaptive charging logic. This allows the charger to intelligently switch between charging from solar panels, the alternator, and hybrid mode (solar and alternator). It also provides a slightly higher charging power of up to 720 watts at 50 amps.
Below is a summary of other key features and specifications of these two DC-DC MPPT battery chargers:
| Renogy Basic 40A DC-DC MPPT Battery Charger | Renogy Pro IP67 50A DC-DC MPPT Battery Charger | |
|---|---|---|
| Model | 40D1S | 2125DS-21W |
| Build Materials | Tough metal casing + plastic | Tough metal casing |
| Dimensions | 195 x 149 x 48 mm (1.2 kilos) | 178.2 x 121.5 x 37.5 mm (1.52 kilos) |
| Charging Logics | Solar or Alternator | Solar, Alternator, or both |
| Maximum Solar Input Voltage | 30 Volts | 50 Volts |
| Maximum Solar Input Current | 45 Amps | 48 Amps |
| Maximum Solar Input Power | 670 Watts | 720 watts |
| Maximum Alternator Input Voltage | 16 Volts | 32 Volts |
| Output Voltage Range | 7V to 16V | 9V to 32V |
| Charging Efficiency | 93% | 94% |
| Solar MPPT Efficiency | 99% | 99% |
| Maximum Charging Current | 40 Amps | 50 Amps |
| Maximum Output Power | 616 Watts | 720W |
| Self Consumption | Under 10mA | Under 100mA |
| Built-in Screen | NO | NO |
| Bluetooth Support | NO | YES |
| Temperature Compensation | N/A | YES |
| Operating Temperature | -4Β°C to 113Β°C (-20Β°F to 45Β°F) | -35Β°C to 80Β°C (-31Β°F to 176Β°F) |
| Battery Type | Flooded, GEL, Sealed/ AGM, & Lithium | Flooded, GEL, Sealed/ AGM, Lithium, & Custom Battery |
| Safety Feature | Overcurrent, overvoltage, over-discharge, over-temperature, reverse polarity | Overcurrent, overvoltage, over-discharge, over-temperature, reverse polarity |
| Regulatory Certifications | CE, RoHS, FCC Path 15 Class B, SAA | CE, RoHS, FCC Part 15 Class B |
How Do the Two Renogy DC-DC MPPT Battery Chargers Compare?
In this section, we compare the two battery chargers across the most critical attributes, starting with charging technology.
What type of battery charger is each model?
Both the 40D1S and the Pro IP67 are DC-DC battery chargers with built-in MPPT solar controllers. However, they differ significantly in their charging logic. The basic 40D1S uses a two-way charging system that switches between alternator-charging mode and solar-charging mode. In contrast, the Pro IP67 adopts a more advanced three-way charging logic, seamlessly switching between alternator-charging, solar-charging, or hybrid-charging modes.
Which charger takes up less space in a van?
If space is a priority in your van or boat, the Pro IP67 is the clear recommendation. It has a remarkably compact design, measuring just 17.8 cm (L) x 12.2 cm (W) x 3.8 cm (H). Its base footprint is nearly the size of an iPhone, allowing it to fit into even the tightest or most awkward spaces.
On the other hand, the basic 40D1S measures 19.5 cm (L) x 14.9 cm (W) x 4.8 cm (H). Its base footprint is closer to that of an iPad Mini, so you'll need slightly more space to mount it.
How tough is the construction?
Both chargers feature rugged metal casings for enhanced durability. However, the Pro IP67 is built for more demanding environments. Its IP67-rated enclosure makes it fully dust-tight and waterproof, capable of withstanding powerful water jets and temporary immersion up to 1 metre. It also offers a wider operating temperature range of -35Β°C to 80Β°C.
The 40D1S is still well-constructed, with its metal casing added with tough plastic inserts on the ends to help absorb shocks from impacts or drops. However, it has a slightly lower operating temperature range of -20Β°C to 45Β°C, and its enclosure is IP31-rated, providing only basic protection against dripping water.
Which systems and batteries are they compatible with?
The Pro IP67 takes the point here as it has more extensive electrical flexibility. For solar charging, it supports up to 720 watts at 15β50V and 0.1β48A. The alternator (starter battery) input accepts 9β32V, making it compatible with both 12V and 24V systems, while the output voltage range of 9β32V allows it to charge either 12V or 24V leisure battery banks.
The basic 40D1S supports a maximum solar input of 670 watts at 12β30V and 0.1β45A. Its alternator input is limited to 11.2β24V (suitable for 12V systems), and it has an output range of 7β16V for charging 12V leisure batteries only.
Note: Both chargers are compatible with Flooded, Gel, Sealed/AGM, and Lithium batteries.
How easy are they to install?
Both models are DIY-friendly, allowing you to set them up on your own without hiring a technician, and both come with integrated terminal leads to simplify wiring even in tight spaces. The chargers include the following basic installation components:
- The Pro IP67 charger kit comes with a battery temperature sensor, mounting screws, lug connectors, and a user manual.
- The basic 40D1S charger kit comes with heat shrink connectors, mounting screws, and a user manual.
The basic charger includes an IGN Signal Wire for connection to the ignition signal port of your caravan, RV, campervan, or boat, but it lacks a terminal lead for a battery temperature sensor. Conversely, the Pro IP67 comes with a temperature sensor cable but does not include an IGN Signal Wire. Instead, it features smarter voltage sensing that triggers alternator-charging mode only when the engine is running. Its IP67-rated enclosure is also a major advantage, as it allows you to mount the unit outdoors, such as in the vehicle's undercarriage, without worrying about damage from dust or water.
How easy are they to operate?
Both chargers are effortless to operate, even for beginners and seniors. However, the Pro IP67 is simpler to use as you only need to select the "battery type" mode for your connected leisure battery. This can be easily adjusted using the built-in "TYPE" button until the dedicated "Type" LED indicator matches your battery type. If desired, you can also configure the Pro IP67 via the Renogy app on your phone or tablet, which lets you adjust various settings, including charging parameters in User Mode for a custom leisure battery bank.
Unfortunately, the basic model does not support User Mode or mobile app configuration. You'll need to use the built-in "Select" button to configure it, including choosing the battery type and switching charging modes. The built-in LED indicators help ensure you select the correct settings for safe and optimal operation.
Which charger is faster?
The Pro IP67 is the clear winner here, thanks to its high 720-watt charging power and 94% efficiency. If your DC energy source can consistently deliver this power, the charger can recharge a 100Ah 12V lithium battery in about 1 hour and 48 minutes. A 100Ah 24V lithium battery will take approximately 3 hours and 38 minutes, as it has greater energy capacity and the charger's efficiency drops slightly to 92% in 24V mode.
By comparison, the basic 40D1S delivers up to 616 watts of output power with 93% charging efficiency. As such, it can recharge a 100Ah 12V lithium battery in about 2 hours and 6 minutes (24V batteries are not supported). While the 18-minute difference may seem small, it can make a significant impact when you're living off-grid.
How do the charging modes work?
If you want to make the most of your solar panels and alternator, the Pro IP67 is the best choice. It can charge your leisure battery from solar, the alternator/starter battery, or both simultaneously (hybrid mode). Its smart, adaptive charging logic automatically selects the power source based on available input, prioritising solar charging and only switching to alternator charging when solar output is insufficient:
- Solar-charging mode: In use when the solar panel setup is generating more than 24 amps; or when solar output is below 24 amps, but the starter battery's voltage meets the minimum requirement.
- Hybrid-charging mode: In use when the solar panels are generating less than 24 amps, and the starter battery voltage meets the minimum requirement; or during the bulk charging stage when solar output exceeds 24 amps and the starter battery voltage remains adequate.
- Alternator-charging mode: In use when the solar output current falls below the set "Low Solar Current Shutdown" value.
For charging stages, the Pro IP67 supports four intelligent algorithms: Bulk, Boost, Float, and Equalization. It can also reactivate lithium batteries that have entered sleep mode after deep discharge. This lithium battery activation function is enabled by default, but you can disable it via the Renogy app.
The basic 40D1S also supports lithium battery activation. However, it only offers three charging stages (Bulk, Boost, and Float), and its charging logic is more limited. It lacks a hybrid-charging mode and prioritises alternator charging by default. If the starter battery voltage drops below the minimum requirement, it switches to solar output until the starter battery voltage recovers. If you prefer the charger to prioritise solar charging, you can configure this mode using the built-in "Select" button. Once enabled, the charger will draw from solar whenever the solar output voltage exceeds 12 volts. If solar voltage drops below 12V, it will switch back to the starter battery until solar output recovers.
Can you monitor them from your phone?
The basic 40D1S relies solely on a built-in button and LED indicators for operation and monitoring. It lacks an integrated display or Bluetooth connectivity for pairing with a mobile device.
By contrast, the Pro IP67 includes a built-in button and LED indicators for quick configuration, plus Bluetooth connectivity for wireless pairing with a smartphone or tablet via the Renogy app. Once paired, you can configure the charger wirelessly, including custom charging parameters in User Mode, and monitor performance in real time, such as charging power (wattage), charging current, charge stage, battery voltages, number of over-discharge events, and other key details.
If desired, you can pair the Pro IP67 with the Renogy ONE Core smart display for a dedicated monitoring screen and extended wireless remote access range. It also features Renogy's CAN communication ports for integration with other advanced Renogy systems.
How much do they cost in Australia?
This may be the only area where the basic 40D1S stands out. Thanks to its limited features and capabilities, it is available for just $220, or as low as $180 during limited-time offers at our store. This is less than half the price of the Pro IP67, which you can get at $540 on regular days or as low as $450 during offers.
However, even with the higher cost, the Pro IP67 is the most worthwhile choice. It provides useful extra features for your adventure vehicle when travelling or camping, along with a longer 5-year warranty compared to the 2-year coverage of the basic model.
Should You Get the Basic or Pro Renogy Battery Charger?
The right option for your caravan, campervan, RV, or boat depends on your budget, power needs, and preferences. We recommend the basic 40D1S DC-DC MPPT battery charger if you:
- Are on a tight budget
- Have enough indoor space to mount it
- Only need a charger that can deliver 500+ watts
- Have a 12V alternator and a 12V leisure battery
- Are comfortable using a charger without monitoring convenience
On the other hand, the Pro IP67 is a better investment if you:
- Have a sufficient budget
- Want a battery charger with real-time monitoring
- Have limited space in your adventure vehicle
- Need a battery charger that can handle extreme conditions
- Want to make the most of both your alternator and solar input
Frequently Asked Questions
Which Renogy DC-DC charger charges a lithium battery faster?
The Pro IP67, with its 720-watt output and 94% efficiency, can recharge a 100Ah 12V lithium battery in about 1 hour and 48 minutes, while the 616-watt 40D1S takes about 2 hours and 6 minutes for the same battery.
Can the Renogy 40D1S charge a 24V battery bank?
No. The 40D1S has an output range of 7β16V, so it can only charge 12V leisure batteries. The Pro IP67's 9β32V output range supports both 12V and 24V leisure battery banks.
Does either charger support Bluetooth monitoring?
Only the Pro IP67 has built-in Bluetooth, letting you configure it and monitor charging power, current, charge stage, and battery voltages in real time via the Renogy app. The 40D1S relies on its "Select" button and LED indicators only.
How much do these Renogy chargers cost in Australia?
The 40D1S sells for $220, or as low as $180 during limited-time offers, and comes with a 2-year warranty. The Pro IP67 costs $540, or as low as $450 during offers, and is backed by a 5-year warranty.
Ready to upgrade your setup? Shop the Renogy 40D1S or the Renogy Pro IP67 at Campervan Builders today and keep your leisure batteries charged on every trip.
