The Studer AJ series brings together pure sine inverters (DC/AC converters) of low and medium power, designed and manufactured in Switzerland for autonomous (off-grid) installations. They convert the DC voltage of a 12, 24 or 48 V battery into 230 V / 50 Hz alternating current of a quality comparable to that of the grid, capable of powering the most demanding electrical appliances without compromise.
The range covers continuous power ratings from 200 VA to 2,000 VA depending on the model (AJ 275 to AJ 2400). The battery and load connection cables are already pre-fitted on the entry-level models, which simplifies installation. The automatic standby mode greatly reduces self-consumption, while the exceptional overload capacity makes it possible to start difficult loads (pumps, motors, tools) without nuisance tripping.
Why choose the AJ series?
Designed for autonomous solar systems, the AJ inverters deliver a pure sine waveform (THD < 3 % on a resistive load) and maintain high efficiency even at partial load, where most consumers actually operate. Their reliability, demonstrated by tens of thousands of systems installed over many years, has made them the reference choice of many off-grid integrators.
- Pure sine waveform 230 Vac ±5 % / 50 Hz quartz-controlled (±0.05 %), compatible with all sensitive electronic devices.
- Battery voltages 12, 24 or 48 V depending on the model, to suit any DC architecture.
- Very low standby consumption (automatic stand-by mode) to preserve battery autonomy.
- High overload capacity (up to 2.5 × rated power for 5 s) for difficult starts.
- Built-in protections: overheating, overload, short-circuit and deep-discharge protection, with automatic restart.
- Built-in PWM solar regulator as an option on certain references (« -S » suffix).
Technical specifications
The table below compares a few representative models of the AJ range, from the most compact (AJ 275-12) to the most powerful (AJ 2400-24), to make selection easier according to battery voltage and the required power.
| Model |
AJ 275-12 |
AJ 350-24 |
AJ 600-24 |
AJ 1000-12 |
AJ 1300-24 |
AJ 2400-24 |
| Battery voltage |
12 V |
24 V |
24 V |
12 V |
24 V |
24 V |
| Continuous power |
200 VA |
300 VA |
500 VA |
800 VA |
1,000 VA |
2,000 VA |
| Peak power (5 s) |
450 VA |
650 VA |
1,200 VA |
2,200 VA |
2,800 VA |
5,200 VA |
| Output |
Pure sine 230 Vac ±5 % / 50 Hz ±0.05 % |
| Max efficiency |
93 % |
94 % |
94 % |
93 % |
94 % |
94 % |
| Standby / no-load consumption |
0.3 / 2.4 W |
0.5 / 3.5 W |
0.6 / 7.2 W |
0.7 / 10 W |
1.2 / 13 W |
1.2 / 16 W |
| Weight |
2.4 kg |
2.6 kg |
4.5 kg |
8.5 kg |
8.5 kg |
18 kg |
The whole range is certified to the Low Voltage 2014/35/EU and EMC 2014/30/EU directives (EN/IEC 62109-1, 62109-2, 62477-1, 61000-3-3, 61000-6-2, 61000-6-4 and 62040-2 standards). Other references complete the range (AJ 400-48, AJ 500-12, AJ 700-48, AJ 2100-12, etc.): contact us to identify the model best suited to your installation.
Strengths & Swiss manufacture
Designed and assembled by Studer Innotec in Switzerland, the AJ inverters are renowned for their robustness and longevity under demanding operating conditions. Their sober design, without a fan on the smallest power ratings, ensures silent operation and excellent durability over time.
- Swiss manufacture, industrial quality and proven durability.
- Complete protections ensuring the safety of the loads and the battery.
- Ideal for autonomous solar, marine, fitted-out vehicles and remote sites.
- Simplified installation thanks to the pre-fitted cables on the smaller power ratings.
Distributed by SINES Export. Discover the full Studer range as well as our complete selection of inverter/chargers for your autonomous installations.
