Product Description

Lenze EVS9321-EP — 9300 Series Servo Position Controller, 0.37kW, 400/480V

Position control in a production machine used to mean a servo drive handling motion commands from an external position controller — a dedicated axis card, a PLC function module, or a separate motion controller that computed trajectories and fed setpoints to the drive. It worked, but it came at a cost: additional hardware, additional wiring, additional programming interfaces to manage, and additional points where timing delays between the host controller and the drive could degrade positioning accuracy.

The EVS9321-EP moves that logic inside the drive itself. It is a 9300 series servo position controller from Lenze — a 0.37kW built-in unit that carries its own complete position controller, sequence control, and motion technology functions as firmware within the inverter, eliminating the external positioning hardware entirely. Electronic gearbox, register control, cam profiler, and homing sequences are all standard capabilities, running on the drive's own processor without relying on a host PLC for trajectory computation.

Genuine Lenze original manufacture. Brand new. In stock and available for immediate worldwide dispatch.

Technical Specifications

Parameter	Value
Lenze Part Number	EVS9321-EP
Lenze Internal No.	00408509
Product Series	9300 Servo
Controller Type	Servo Position Controller
Variant	Standard (EP)
Design	Built-In Unit
Rated Motor Power	0.37kW (0.5HP)
Rated Output Current	1.5A
Peak Output Current	Up to 2× rated (3.0A)
Mains Voltage (rated)	400/480V AC 3-phase
Mains Voltage Range	320–528V AC ±0%
Mains Frequency	50/60 Hz
DC Bus Voltage Range	450V DC (−0%) to 620V DC (+0%)
Output Voltage	0–480V AC (variable)
Operating Temperature	0°C to +55°C (IEC/EN 60721-3-3 Class 3K3)
Storage Temperature	−25°C to +55°C (Class 1K3)
Transport Temperature	−25°C to +70°C (Class 2K3)
Restart Delay (min.)	3 minutes between switching off and restarting
IP Rating	IP20
Mounting	Panel mount / built into machine
Weight	~4.1kg (8.99 lbs)
Communication Interface	AIF slot — pluggable fieldbus modules
Feedback Systems	Resolver, SinCos encoder, incremental encoder (TTL), KTY sensor
Technology Functions	Electronic gearbox, positioning, register control, cam profiler

Understanding the 9300 Series: EVS vs EVF, and What "-EP" Means

Lenze's 9300 platform covers two distinct product lines that share the same power stage technology but differ fundamentally in their motion control architecture.

The EVF93xx range are vector frequency inverters — variable speed drives for asynchronous induction motors, focused on speed control with high torque linearity. They cover the same 0.37–90kW power range and use the same cabinet format as the servo family, but their control algorithms and feedback requirements are aligned to three-phase AC induction motor operation.

The EVS93xx range are servo inverters — designed specifically for synchronous servo motors with precision position and velocity feedback. They operate with resolver or SinCos encoder feedback to achieve the closed-loop current and position accuracy that servo applications demand. The difference is immediately relevant at specification time: pairing an EVS controller with a standard asynchronous motor, or using an EVF controller where a servo motor and precision positioning are required, will not produce the intended result.

Within the EVS9321 family, the suffix after the hyphen defines the control variant:

EP — Servo Position Controller. Full positioning capability with built-in sequence control, electronic gearbox, register control, and cam profiling. This is the EVS9321-EP.
ES — Servo Speed Controller. Speed and torque control without the integrated position management of the EP variant.
EI — Basic servo inverter without the extended technology functions of the EP or ES variants.
EK — Servo cam profiler (a specialised variant for cam-based motion profiles).

The EP designation is therefore the most capable standard variant in the EVS9321 family — incorporating all of the 9300's position control and motion technology functions in a single built-in unit.

Built-In Position Control: What It Replaces and Why It Matters

In a conventional servo axis using a speed-controller drive, position management is handled externally. The PLC or motion controller computes the desired position trajectory, converts it to speed setpoints or incremental pulse commands, and sends those to the drive at every control cycle. The drive executes the speed command and reports actual position back. Round-trip communication latency between the host and the drive limits achievable update rates and introduces timing jitter that sets a practical ceiling on positioning precision, particularly on fast-moving axes or in multi-axis synchronisation applications.

The EVS9321-EP eliminates that round trip for the position control loop. The position controller runs inside the inverter at the drive's own processor speed, closing the position loop locally without waiting for a host control cycle. Position targets, homing sequences, and move profiles are stored and executed in the drive itself. The host PLC can issue high-level commands — "move to target X," "start sequence 3," "home the axis" — rather than managing position trajectory computation directly.

This architecture reduces the processing load on the host controller, allows shorter positioning cycle times than host-managed approaches, and simplifies PLC programming significantly for applications with complex positioning sequences. The drive handles the precision; the PLC handles the machine logic.

Motion Technology Functions Built Into the EP Variant

Four key technology functions ship as standard capabilities in the EVS9321-EP firmware:

Electronic Gearbox — A real-time synchronisation function that couples one or more drives to a master axis or master frequency signal with a programmable gear ratio. Multiple drives can be held in exact angular synchronisation to the master without any mechanical coupling shaft. This replaces mechanical line shafts in web processing, printing, labelling, and converting machines — eliminating the mechanical components while providing the flexibility to change the gear ratio through parameter adjustment rather than physical gearbox replacement.

Positioning Control — A complete single-axis position controller with sequence control. Positioning tasks are defined by target position, velocity, acceleration, and deceleration parameters, stored in the drive, and executed on command. Limit switch inputs, homing functions, and automatic material correction for processes where initial position tolerances are large are all integrated. Commissioning requires minimal parameter input compared to externally programmed position controllers.

Register Control — An overlay alignment function designed for web-fed processes. In printing, cutting, perforating, and splicing applications, the register control monitors the position of a print mark or reference feature relative to a processing station (knife, print head, embossing die) and continuously corrects the angular position of the processing roll to maintain registration. Drift errors accumulate in processes where material tension and stretch vary; register control eliminates accumulated drift without requiring a separate register controller module.

Cam Profiler — Stores up to 8 independently programmable cam profiles in the drive. Each profile defines the output axis motion as a function of master axis position — equivalent to a mechanical cam but entirely defined in software. Profile switching can occur during production without stopping the machine, enabling product changeovers (different cut lengths, perforation patterns, embossing depths) without the setup time that physical cam replacement requires.

AIF Interface: Fieldbus Integration Without Changing the Drive

The EVS9321-EP carries an AIF (Automation Interface) slot on its front panel — a proprietary Lenze interface for pluggable communication modules. The AIF slot accepts modules for the major industrial fieldbus protocols, allowing the same EVS9321-EP hardware to communicate on different network types by swapping or adding the communication module.

Available AIF modules cover PROFIBUS DP, CANopen (including CAN synchronisation for multi-axis coordination), DeviceNet, and other protocols. The keypad module (XT EMZ9371BC and variants) plugs into the same AIF slot and can be connected or disconnected during operation — useful for commissioning and parameter adjustment in the field without requiring a laptop or serial connection.

This modularity means the EVS9321-EP can be specified before the final fieldbus choice is made, or standardised across machines that communicate on different networks. A single drive variant serves both PROFIBUS and CANopen installations; only the communication module changes.

Feedback Compatibility: Resolver, SinCos, Incremental

Closed-loop servo operation requires continuous high-resolution feedback of rotor position and velocity. The EVS9321-EP is compatible with three feedback types commonly found on Lenze and third-party servo motors:

Resolver — The classical two-pole resolver is an analogue feedback device with no internal electronics, making it extremely robust in high-vibration and high-temperature environments. Resolver feedback is standard on many Lenze servo motors and provides position resolution sufficient for demanding positioning applications.

SinCos encoder — A high-resolution analogue incremental encoder producing sinusoidal A and B channels. Interpolation within the drive achieves effective resolutions significantly higher than the encoder's physical line count, enabling very fine position resolution and smooth low-speed operation. SinCos feedback is the preferred option for applications requiring the highest positioning precision.

Incremental TTL encoder — Digital quadrature encoder with TTL-level outputs. Compatible with a wide range of standard encoders and useful for applications where an existing encoder needs to be retained.

Motor temperature monitoring via KTY temperature sensor is also supported, providing thermal protection that shuts down the drive before winding overtemperature causes motor damage.

Frequently Asked Questions

Q: What is the difference between the EVS9321-EP and EVS9321-EK?

A: The EVS9321-EP is the servo position controller variant — it includes the full position controller with sequence control, electronic gearbox, register control, and cam profiling as standard functions. The EVS9321-EK is the dedicated cam profiler variant, optimised specifically for cam profile applications with different firmware and function code structure. For general positioning and synchronisation applications, the EP is the appropriate choice. For pure cam profile applications with specific requirements around profile definition and switching, the EK may be specified instead.

Q: Does the EVS9321-EP require an external position controller?

A: No. The position controller is fully integrated into the EVS9321-EP firmware. Target positions, velocities, accelerations, homing sequences, and move profiles are stored and executed within the drive itself. The host PLC issues high-level commands and monitors status via the fieldbus or digital I/O — it does not need to compute position trajectories or manage position loop timing.

Q: What motor types is the EVS9321-EP designed for?

A: The 9300 EVS series is designed for synchronous servo motors — brushless AC servo motors with precision position feedback (resolver or SinCos encoder). It is not designed for standard three-phase asynchronous induction motors; those applications use the EVF93xx vector inverter range. Using the EVS9321-EP with a standard induction motor will not produce correct operation. The drive is optimised for Lenze's own servo motor range but can be commissioned with compatible third-party servo motors with appropriate parameter configuration.

Q: What fieldbus systems does the EVS9321-EP support?

A: Communication is handled through the pluggable AIF interface module slot on the drive front panel. Available modules support PROFIBUS DP, CANopen (including CiA 402 motion profile), DeviceNet, and other protocols. The drive ships without a communication module — the appropriate AIF module must be ordered separately based on the network in use. Without a fieldbus module, the drive operates via its digital and analogue I/O terminals and local parameter settings.

Q: What is the minimum restart interval after switching off?

A: A minimum of 3 minutes must pass between switching off and restarting the EVS9321-EP (and EVS9322-EP). This interval allows the DC bus capacitors to discharge and internal temperatures to stabilise before re-energisation. Ignoring this interval — particularly during repeated test cycling during commissioning — risks damage to the power stage. For safety-related frequent mains disconnections, the Safe Torque Off (STO) function available in the Vxx4 variants should be used instead of switching the mains supply.

Q: Can the EVS9321-EP operate on 460V North American supply?

A: Yes. The permissible mains voltage range is 320–528V AC three-phase, which covers standard North American 460V supplies at both 50Hz and 60Hz. The rated voltage on the nameplate is 400/480V; supplies anywhere in the 320–528V band are fully supported.

Q: What is the peak current capability of the EVS9321-EP?

A: The EVS9321-EP (and EVS9322-EP) can supply up to twice the rated output current as peak current — 3.0A peak against the 1.5A rated continuous current. This peak capability is used during acceleration phases where peak torque demand exceeds the continuous rating. The overcurrent duty cycle is defined as a maximum of 10 seconds overcurrent duration within a 60-second cycle at not more than 44% of rated current during the base load portion. Exceeding this duty cycle or setting C0022 above 1.5× rated current causes the drive to enter overcurrent protection mode.

EVS9321-EP Brand New Lense Inverter EVS9321EP