In the field of high-precision motion control, ETEL's Accuret MODULAR series has become the preferred solution for industries such as semiconductor manufacturing, precision machine tools, and laser processing due to its modular architecture, powerful control algorithms, and flexible power configuration. This series covers three voltage levels of 300V, 400V, and 600V, each of which provides controllers and matching power modules with multiple current specifications to adapt to different application scenarios from light load single axis to heavy load multi axis. This article is based on official technical data and conducts in-depth analysis from five dimensions: hardware specifications, control performance, advanced functions, communication interfaces, and selection logic, providing engineers with a systematic technical reference.
Series Overview and Positioning
The Accuret MODULAR series is essentially a combined drive system designed to separate the position controller (model EA-P2M) from the power module (model EA-S0M or EA-SOM). The controller is responsible for closed-loop computation, trajectory generation, and I/O management, while the power module is responsible for bus voltage conversion and power output. This separation design brings two major advantages: firstly, it can independently upgrade the power capacity according to the load demand, without the need to replace the control board; Secondly, the same controller platform can be shared, and different bus voltages (300V, 400V, or 600V levels) can be adapted by simply replacing the power module, greatly reducing spare parts inventory and system modification costs.
The core differences among the three sub series lie in the DC bus voltage range and maximum output current:
300 series: Bus voltage of 48-340 VDC, suitable for low-voltage servo systems, typical applications such as small linear motor platforms and high-speed mounting heads.
400 series: Bus voltage of 48-400 VDC, covering a wider range of AC inputs (single-phase or three-phase 100-400 VAC), is currently the most commonly used version in industrial sites.
600 series: Bus voltage of 200~600 VDC, only supports three-phase 142~424 VAC input, designed specifically for high-power, high-voltage large and medium-sized equipment, such as heavy-duty gantry milling machines and large curved printing machines.
The control core (processor, algorithm, sampling period) of each series is completely consistent, ensuring cross series software compatibility. Engineers only need to focus on power matching.
Detailed specifications of controller module
1. 300V level controller (EA-P2M-300)
This level offers two controller models:
EA-P2M-300-4/7.5A: Each axis continuously outputs 4 Arms, with a peak pulse current of 7.5 Arms (lasting for several milliseconds). The PWM switching frequency is fixed at 10 kHz (it can also be configured to 20 kHz to reduce audio noise, but slightly lower the maximum output capacity).
EA-P2M-300-07/15A: Continuous output of 7.5 Arms, peak output of 15 Arms. This model is suitable for driving medium inertia motors or acceleration and deceleration scenarios that require short-term overload.
Both controllers are designed with dual axis, with independent current loops on each axis, which can simultaneously drive two linear or rotary motors. The power input is a DC bus with rated currents of 8 A (4/7.5A model) and 10 A (07/15A model), and an external rectifier power supply that meets the voltage range is required. The controller is equipped with a safety power relay that can quickly cut off the output bridge arm in case of a fault, meeting the safety requirements of EN 61800-5-1.
2. 400V level controller (EA-P2M-400)
This level offers three models, covering a wider current gradient:
EA-P2M-400-05/10A: Continuous 5 Arms, peak 10 Arms.
EA-P2M-400-10/20A: continuous 10 Arms, peak 20 Arms.
EA-P2M-400-15/40A: continuous 15 Arms, peak 40 Arms.
All three controllers support adjustable PWM frequencies of 10 kHz or 20 kHz, and the maximum bus input current is 30 Arms (all models are the same). However, the actual available current is limited by heat dissipation and internal components, so the heavy-duty model (15/40A) requires better heat dissipation conditions. In terms of weight, the first two models are 3.3 kg and the third model is 4 kg, with the main difference being the size of the power module. The 400 series controller is the most popular in industrial automation, and its voltage range is compatible with the vast majority of 380 VAC industrial power grids (about 537 VDC after three-phase rectification, but the upper limit of the controller is 400 VDC, so it is important to note that the front-end voltage should not exceed the limit, and it is recommended to use below 380 VAC in practice).
3. 600V level controller (EA-P2M-600)
This level only offers one standard model:
EA-P2M-600-15/40A: continuous 15 Arms, peak 40 Arms, PWM frequency can be set to 5 kHz or 10 kHz (switch loss is lower at 5 kHz, suitable for higher bus voltage). Its bus voltage range is 200~600 VDC, which can be directly used for 600 V DC links. The AC input requires three-phase 142~424 VAC (50/60 Hz), maximum input current of 10 A, and peak surge current of 15 A (@ 424 VAC). The weight is 4 kg, which is the same as the 400 level heavy-duty model.
It is worth noting that the "maximum continuous power" of the 600 series controller is labeled as 7.3 kW (three-phase input), while the 400 series is not explicitly stated, but can be calculated based on voltage and current. The 600 series is suitable for long-distance driving scenarios that require high voltage to reduce cable losses, or heavy-duty applications that require high power output.

Specification and selection of power module
The power module provides a rectified DC bus for the controller and also serves as an auxiliary power supply (24 VDC) output for external sensors or circuit breakers.
300/400 series power supply (EA-S0M-300-40/80A and EA-S0M-400-40/80A)
Both have similar external dimensions (130 × 182 × 75 mm) and provide a continuous current capacity of 40 Arms per axis, with an overload peak of 80 Arms (short pulse). The difference is that the 300 series power supply has a single-phase input of 71~240 VAC, a maximum AC current of 15 A (@ 240 VAC), and a continuous power of about 2.4 kW; while the 400 series power supply supports single-phase or three-phase 100~400 VAC, with a maximum AC current of 10 A (but the continuous power is limited by the input current and is actually 2.8 kW single-phase or 4.8 kW three-phase). The auxiliary outputs of both are 24 V ± 10%/10 A, and the auxiliary inputs are also the same (24 V/10 A, used for external emergency power supply).
The power module integrates soft start and surge limiting circuits internally, with a maximum surge current of 15 A (under 280 VAC conditions), effectively reducing power on shock. Simultaneously providing overcurrent, overvoltage, and undervoltage protection, and indicating the operating status through status LEDs.
600 series power supply (EA-SOM-600-40/80A)
The model name of the power supply includes "SOM" instead of "S0M", indicating that its internal topology is optimized for high voltage. The input only supports three-phase 142-424 VAC, maximum AC current of 10 A, surge peak of 15 A @ 424 VAC, and maximum continuous power of 7.3 kW. The DC output bus is 200-600 V, with a continuous current of 10 Arms (limited by the input current), but the pulse current can reach 80 A. The auxiliary output is also 24 V ± 10%/10 A. Due to the high voltage level, the power supply adopts thicker insulation and larger safety spacing, and the size is correspondingly increased (250 × 246 × 50 mm, but the height may be higher).
When selecting, it should be noted that the rated current of the power supply (40/80A) refers to the bus current capacity that can be provided to the controller, but the actual output is still limited by the AC input capacity. For example, the 400 series power supply can reach 4.8 kW for three-phase input, but if it is single-phase input, it will be reduced to 2.8 kW. It is necessary to choose according to the on-site power supply conditions.
Control performance and core parameters
All Accuret MODULAR controllers share the same real-time control architecture, with the following key sampling times:
Current loop sampling: 50 µ s (i.e. 20 kHz update rate), capable of achieving extremely high current response bandwidth, suitable for low inductance linear motors.
Position loop sampling: 50 µ s (synchronized with the current loop) to ensure the speed of the position loop.
Motion planning and command management: 400 µ s (can be reduced to 200 µ s through configuration), responsible for trajectory generation, interpolation, and command buffering.
The basic motion curves include trapezoidal, S-shaped, sine shaped, and any curve in the form of a lookup table. More complex interpolation motions (such as CNC tool paths) require coordination with the upper level UltimET motion controller and transmission through the TransnET real-time bus. The controller is equipped with a built-in trajectory filter, which can suppress mechanical resonance and support force control mode (with or without external force sensors), achieving constant force contact with zero dwell time, significantly improving the processing quality of grinding, polishing and other processes.

Advanced features and intelligent algorithms
The core difference between this series and ordinary servo drives lies in its embedded intelligent algorithm suite:
Dual encoder feedback management: supports simultaneous connection of motor side encoder and load side linear encoder, eliminating positioning deviation caused by mechanical transmission clearance or thermal expansion through internal position error compensation. This function is crucial for ultra-high precision applications such as lithography machines and wafer inspection tables.
Tooth slot and friction compensation: Based on learning algorithms, automatically identify the motor tooth slot torque and guide rail friction, generate feedforward compensation, make low-speed motion smoother, and reduce speed fluctuations by more than 80%.
Longmen control: For the dual drive Longmen structure, the controller has a built-in cross coupling algorithm to compare the position deviation of the two axes in real time, output adjustment torque, and significantly shorten the synchronization setting time (experimental data shows that it can reduce 50% of the stabilization time).
Quick trigger (1D/2D): Based on theoretical or actual encoder position, output hardware trigger signal when the position reaches the set value, with a response time of less than 20 ns (nanosecond level), suitable for high-speed flying, dispensing synchronization triggering and other scenarios.
Safe stop algorithm: When overspeed, overtravel, or communication loss is detected, a controlled emergency stop is automatically executed to ensure safety and avoid mechanical impact damage to precision components.
Identification and tuning tool: Provides frequency sweep and step response identification functions, automatically calculates optimal PI parameters, and generates performance evaluation reports to reduce on-site debugging time.
In addition, the RTV (Real Time Values) function provides 8 real-time data channels per axis (such as speed, acceleration, torque, position error, etc.), which can be uploaded to the upper computer through the bus in 100 µ s cycles for process monitoring and predictive maintenance.
Communication and Programming Interface
The controller comes standard with three communication ports:
USB 2.0 (full speed 12 Mbps): Only used for local parameter settings and firmware upgrades, does not support real-time control.
Ethernet (10/100 MHz): Supports TCP/IP protocol, used for non real time data exchange with the upper computer (such as status monitoring, recipe download).
TransnT (1 Gbps): ETEL exclusive real-time Ethernet bus, with a minimum cycle time of 50 µ s (typical 100 µ s), supports multi axis synchronization, real-time position/torque command transmission, and is the core link for high-speed linkage applications.
The encoder interface is compatible with EnDat 2.1/2.2 (RS485), digital TTL (orthogonal or clock/data, up to 10 MHz input), and analog 1 Vpp sine/cosine (up to 500 kHz). User I/O includes 5 digital inputs/2 digital outputs per axis (configurable for fast capture or limit), as well as 4 common fast inputs/outputs (response time in microseconds). If more analog signals are needed, an optional expansion board can be used to add 8 digital I/O channels and 4 16 bit analog I/O.
Software development supports C/C++/. NET environments on Windows 7/8/10 (32/64 bit) and provides real-time extension support for RTX2016 and RTX64. ETEL provides an EDI (Device Interface) dynamic link library, which, when combined with ComET debugging software (graphical interface), can quickly complete parameter tuning, waveform oscilloscope, and firmware online upgrades.
Practical Selection Guide
Based on typical application requirements, it is recommended to choose according to the following steps:
Determine the bus voltage: If there is already a DC power supply on site (such as 48V, 300V, 600V), directly match the corresponding series; If using an AC power grid, the peak voltage after rectification should be considered (single-phase 220V rectification is about 310V, suitable for the 300 series; Three phase 380V rectification is about 537V, exceeding the upper limit of the 400 series, and the 600 series must be selected. Note that although the 400 series is labeled as 400VDC, it can actually withstand 400V, so it cannot be used after three-phase 380V rectification. It is necessary to add a transformer to reduce the voltage or choose the 600 series.
Calculate continuous/peak current: Calculate the maximum continuous load current and acceleration/deceleration peak current of each axis, and compare them with the continuous/peak parameters of the controller. For example, if a certain axis lasts for 6 Arms and has a peak of 12 Arms, EA-P2M-400-10/20A can be selected (continuous 10A is satisfied, with a margin for peak 20A). Note that when multiple axes are running simultaneously, the total current of the power module needs to be accumulated.
Evaluate power supply capacity: The AC input capacity of the power module must be higher than the total output power of the controller. For example, for two 15/40A controllers (each with a maximum output power of about 15A × 400V=6kW, and two with 12kW), it is obviously insufficient to choose EA-S0M-400-40/80A (three-phase 4.8kW). At this time, a larger independent power source should be considered.
Additional functional requirements: If force control or dual encoders are required, all series support them without the need for additional hardware. But the gantry control requires at least two axes, so a dual axis controller must be selected.
Environment and Installation: The width of the 300/400 series controller is 130mm, while the 600 series is wider (259mm), and the control cabinet space needs to be checked in advance.
