Aerotech NDrive HL linear drive maintenance replacement

Aerotech NDrive HL linear drive maintenance replacement

In the extension and transformation of industrial motion control systems, replacing discontinued servo drives is often more complex than debugging new equipment. Engineers not only need to verify current, voltage, and size, but also confirm feedback type, communication network, I/O logic, position synchronization output, and regenerative energy processing. The Aerotech NDrive HL is a network digital linear drive in the Automation 3200 motion system, which uses linear power levels and features low noise, zero crossover distortion, and high bandwidth. It is suitable for ultra precision machining, optical inspection, nano positioning, and other applications that require high dynamic performance and electromagnetic interference. This article summarizes the key technical information of NDrive HL from the perspectives of maintenance, troubleshooting, and replacement selection.

Model and core specifications of NDrive HL

NDrive HL mainly includes three basic models: HL 20-40, HL 10-40, and HL 10-80. HL 20-40 adopts a ± 40 VDC bus with a peak output current of 20 A and a continuous output current of 10 A. HL 10-40 is also a ± 40 VDC bus with a peak value of 10 A and a continuous output current of 5 A. HL 10-80 adopts a ± 80 VDC bus with a peak value of 10 A and a continuous output current of 5 A. The continuous power coverage is about 675 W to 1350 W, and the peak power is about 675 W to 1350 W. The main power input is 100, 115, 200, 230 VAC, 50/60 Hz, single-phase, depending on the model configuration.

Linear power level is different from PWM power level. Each phase of NDrive HL can be rail to rail output, as its driving power supply is not directly taken from the positive and negative busbars. The power amplifier has a gain of 2, 1, and 1 A/V per phase, a bandwidth of approximately 2 kHz, a minimum load inductance of 0 mH, and a minimum load resistance (line to neutral) of 0.5 Ω. This means that HL can drive low inductance, low resistance linear motors or voice coil motors, while ordinary PWM drivers may be limited by current ripple and heat generation. Linear amplifiers have no PWM switching noise, resulting in extremely low EMI/RFI emissions, making them suitable for noise sensitive measurement and imaging devices.

The working environment temperature is 0-50 ° C, the storage temperature is -30-85 ° C, the humidity is up to 80% below 31 ° C, and then linearly decreases to 50% at 40 ° C. It is non condensing and has an altitude of up to 2000 meters. The weight is about 22.0 lb (9.98 kg), and after installing - IOPSO or - IOPSO H, it is about 22.2 lb (10.07 kg). The temperature of the chassis may exceed 75 ° C in some applications, so it is necessary to leave one inch of free air space during installation and be aware of the risk of burns.

Feedback, I/O, and communication capabilities

NDrive HL supports brushless, brushed, and stepper motors. The standard feedback is a line driven square wave or analog sine orthogonal encoder. The main encoder channel J207 receives Sin/Sin-N, Cos/Cos-N, Marker/Marker-N, 0-5 VDC RS-422 differential signals, with a maximum encoder signal of 8 MHz. After x4 orthogonal decoding, it can reach 32 million counts/s. Optional MXH analog encoder multiplication supports up to 200 kHz input frequency, multiplication factor 1-512, with a maximum of x2048 when combined with controller x4. MXH supports PSO and real-time orthogonal output, but after changing the multiplication parameters, internal erasing and reprogramming take about 3.5 minutes, during which the LED will flash and the axis cannot be enabled.

In terms of I/O, the standard configuration includes 4 optical isolated outputs, 6 optical isolated inputs (including 2 high-speed inputs), 2 differential analog inputs (one standard and one provided with IOPSO), and 2 analog outputs. -The IOPSO expansion board adds 8 optical isolated inputs, 8 optical isolated outputs, 2 18 bit analog outputs, and 2 16 bit differential analog inputs SSI Net、 Absolute encoder interface and brake relay. -IOPSOH increases the output to 1 A per channel. If PLC type I/O expansion is required, an optional - ENET 10/100BASE-T Ethernet port can be used to connect third-party I/O via ModBus TCP.

The communication core consists of FireWire J201, J202, and J203, with a speed of 400 Mbps and three ports connected in parallel. The multi axis system recommends a star daisy chain with a maximum of 32 axes, and a single chain with a maximum of 16 drivers. Each NDrive HL must be assigned a unique communication channel number through the S2 switch, usually numbered sequentially starting from 1. RS-232/RS-422 J206 is mainly used for firmware upgrades and auxiliary communication. When replacing, it is necessary to confirm the FireWire topology, channel number, and controller axis mapping of the original system, otherwise the new drive may not be recognized.

PSO, MXH and multi axis laser triggering

Position synchronization output is a key function of NDrive HL in laser processing, visual inspection, and aerial photography. The standard single axis PSO can track the main encoder, auxiliary encoder, SSI Net, or software trigger, with a single axis tracking rate of up to 20 MHz and a trigger delay of about 200 ns. - DUALPSO and - TRIPLEPSO support two - or three-axis vector position triggering with a delay of about 275 ns, and the multi axis tracking rate is limited to 5 MHz. The PSO hardware uses a 255 level FIFO queue internally, with programmable pulse configuration, window mode, data capture, and data update modes. Output options include high-speed optical isolation J301, J205 output 11 (up to 1 kHz) or RS-422 Marker output (up to 10 MHz).

MXH is closely related to PSO. When using - DUALPSO or - TRIPLEPSO, if the encoder data rate is too high, the PSO tracking rate should be limited to 5 MHz through CfgFbkEncMxhQuadDiv or PSOTRACK SCALE while maintaining full resolution of the servo loop. SSI Net J302/J303 provides two bidirectional RS-422 channels for daisy chain encoder signals, sending the second/third axis encoders to drivers with - DUALPSO/- TRIPLEPSO. The maximum data rate of SSI Net is 20 MHz, requiring the use of a dedicated SSI Net cable and configuration of parameters such as PsoSsiConfig and PsoSsi2Config. If the original device uses multi axis laser triggering, these cables and parameter configurations must be retained during replacement.

Rotary input and - RDP options

NDrive HL optional - RDP rotary input, providing two industry standard rotary or Inductosyn channels, each channel can be independently configured as a rotary or Inductosyn input. The standard reference output frequency is 10 kHz, which can also be configured at the factory as 5 or 7.5 kHz. Sine and Cosine feedback signals should be adjusted to 2 V RMS (2.8 V peak) through CfgFbkRDGain. The rotary transformer can be physically aligned with the motor through MSET CNC programming commands, or the relationship can be defined through CfgMotOffsetAng.

Using the Encoder Feedback Configuration tool can quickly optimize RDP alignment. CfgFbkRDGain defines the peak amplitude of the reference sine wave, while CfgFbkRDcosPhase defines the phase delay of the Cosine phase of the biphasic oscillator, mainly used for Inductosyn, and can also compensate for large phase lag caused by rotation. When using Cosine phase adjustment, the JP1 or JP2 of the channel should be set to 2-3, and the corresponding bit of CfgFbkRDConfig should be set to 1. There are two ways to initialize the commutation of brushless motor rotary feedback: R/D automatic configuration or Hall effect initialization. R/D automatic configuration is usually not suitable for Inductosyn because it has multiple electrical cycles per revolution. In dual loop mode, the position source generates commutation initialization, while the velocity source maintains commutation position after enabling.

Motor wiring and phase adjustment

When wiring brushless motors, motor A/B/C must correspond correctly with Hall A/B/C. The forward motion command should cause the motor to rotate clockwise when viewed from the mounting flange. If the direction is opposite, any two-phase motor wires can be exchanged. Hall signal connected to J207: Hall A pin 10, Hall B pin 5, Hall C pin 11. You can observe the Hall status on the Nstat diagnostic page and determine the phase based on it. In terms of encoder phase, the forward motion command should increase the encoder count. If the count decreases, Sin and Sin-N can be exchanged, or CfgFbkTelMultiplier and CfgFbkPosMultiplier can be inverted. When configuring the dual loop, only the feedback parameter of the wrong reverse connection is taken.

When the brushed motor is in torque mode, the positive command should cause the motor to rotate clockwise, corrected by swapping the A/C motor wires. When equipped with a speed measuring machine feedback, the speed measuring machine can be connected to TB302 or J205, using analog input 0. The voltage of the speedometer should not exceed ± 10 V, otherwise the speed loop may be unstable and cause runaway. If necessary, add a resistor voltage divider network and a 1 µ F capacitor filter. The forward command of the stepper motor is clockwise. If it is the opposite, switch the 0A and 0B terminals. The limit switch includes CW, CCW, and Home, connected to J207 pins 12, 24, and 22. You can also use J205 input 8-10 to configure limit settings through DriveIOConfig bit22. ESTOP requires an external fail safe emergency stop circuit for TB201 input, with an input voltage of 5-24 V. If it exceeds this range, a series resistor current limiting is required. If ESTOP is enabled in FaultMask, this input must be driven to avoid emergency stop faults.

Voltage current mode and independent operation

Firmware 2.06 and above supports voltage current mode. This mode allows NDrive HL to function as an independent current controller, receiving ± 10 V torque commands from external position/speed controllers, without the need for real-time FireWire connection, but parameter configuration still requires A3200 software. Pay attention to current loop parameters, feedback configuration, commutation information, and current limits during configuration. After parameter verification, execute FLASHWRITE 1 0 0 through NDebug to save to flash memory, then power off, set DIP switches 6 and 7 to OFF, and power on again to enter voltage current mode.

In this mode, analog input 0 is used as the current/torque command, with+10 V corresponding to negative peak current and -10 V corresponding to positive peak current. Input 8 is used as the enable and output 8 is used as the fault output, both of which are of fail safe polarity. The fault may come from driver overcurrent, motor RMS overcurrent, motor thermistor overheating, amplifier temperature fault, or bus power failure. For the application of replacing old centralized control systems, this mode can extend the service life of NDrive HL on non A3200 platforms.

Common faults and troubleshooting

Motor loss of control is usually related to the reverse connection of the encoder Sin/Cos, incorrect feedback direction, or incorrect commutation phase. The brushless motor does not rotate, and the common reason is that the relative order of motor A/B/C and Hall A/B/C is incorrect. The amplifier malfunctioned during motor deceleration, possibly due to excessive regenerative energy causing bus overvoltage, and requires evaluation or external regeneration treatment. Frequent amplifier failures may be caused by RMS overcurrent, overheating, or internal power supply faults, and current should be reduced, ventilation improved, or repaired.

LED is a fast diagnostic entry point: Limit+and LMT - indicate positive/negative limit, FAILT indicates axis fault, POS ERR indicates position error exceeding limit, ENABLE indicates axis enable, KERNEL indicates controller operation, RMS indicates RMS current exceeding limit, CLMT indicates current limited, INPOS indicates in place, ACTV indicates reset, Power indicates control power supply. Test point TP4 on the control board is for signal sharing. The motor power board test points include TP1+12V, TP2-12V, TP3+5V, TP4 common, and TP10-TP12 common for each phase. The fuses F1, F3, and R6 on the power board are welded, and F2 is a socket type. The motor power boards F1 and F2 are socket type, and F3 is welded. Battery B1 is a 3V button battery, model BR1225.

Engineering process for replacing discontinued modules

When replacing discontinued NDrive HL or other brands of linear servo modules, it is recommended to follow the following sequence:

Record original module parameters: model, peak/continuous current, bus voltage, AC input, feedback type, communication interface, I/O quantity, PSO axis number MXH/MXU、 Brake output, ESTOP logic, size, and heat dissipation.

Match motor: Confirm brushless/brushed/stepper, pole pairs Hall、 Encoder resolution, rotation or Inductosyn. If the original system uses a rotary converter, HL needs to choose - RDP; If using an analog sine encoder, choose - MXH.

Confirm power supply and regeneration: HL supports 100/115/200/230 VAC single-phase, optional - AUXPWR, - ENET, - IOPSO/- IOPSOH. Linear drives do not have internal shutdowns and require external processing of regenerated energy.

Confirm network: FireWire topology, S2 channel number, controller axis mapping. When Ethernet I/O is required, select - ENET.

Confirm I/O and PSO: When standard I/O is insufficient, select - IOPSO or - IOPSOH; Dual axis/three-axis laser trigger selection - DUALPSO/- TRIPLEPSO; PSO output optoelectronic isolator selects PSOOPTO1-4 based on speed/voltage.

Mechanical and Heat Dissipation: HL weighs approximately 22 pounds and requires one inch of free air space. The ambient temperature should not exceed 50 ° C, and the chassis temperature may exceed 75 ° C. Be careful of burns.

Power on test: Do not connect the motor first, check the LED, FireWire, ESTOP, and logic power supply; Connect the motor for low-speed testing of phase, feedback direction, limit, and PSO; Finally, gradually load and check the current, temperature, and tracking error.

If the original device uses PWM drivers, attention should be paid to the differences in HL: HL is a linear power level with low noise and zero crossover distortion, but it has lower efficiency and generates more heat, requiring stronger heat dissipation and regeneration treatment. CP is cost sensitive, HP supports higher current and rotation, MP has ultra compact DC input, and CL is cost sensitive linear. When replacing, it is not enough to only look at the installation size and current. Feedback, communication, and functional options must be checked.

Preventive Maintenance and FAQ

Preventive maintenance should check the chassis, cooling vents, cables, and connectors monthly. Turn off the power during cleaning, use a dry soft cloth, and if necessary, slightly wet water or isopropanol. Do not allow liquids to enter the connector. The internal high voltage may still exceed 60 V after a power outage, and maintenance must be carried out by qualified personnel.

NDrive HL 20-40、 How to choose between 10-40 and 10-80?

Select based on peak and continuous current, bus voltage: 20-40 is 20/10 A, ± 40 VDC; 10-40 is 10/5 A, ± 40 VDC; 10-80 is 10/5 A, ± 80 VDC.

Can I directly replace other brands of linear servo drives?

It cannot be judged solely based on current and size. It is necessary to verify the motor type, feedback, commutation, FireWire network, I/O, PSO, ESTOP, and regeneration processing.

Does HL support rotation?

Support, the - RDP rotary input option needs to be selected, providing single/dual channel, 10/7.5/5 kHz carrier frequency.

Can MXH and PSO be used simultaneously?

HL's MXH supports PSO and real-time orthogonal output, but attention should be paid to the 5 MHz tracking limit of multi axis PSO and MXH clock settings.

How to wire ESTOP?

TB201 input 5-24 V, driven by an external fail safe emergency stop circuit, with current limiting resistors in series if necessary, and noise suppression added.

How to connect a multi axis system?

Through FireWire star daisy chain, up to 32 axes, with a single chain of 16 drivers, each driver is assigned a unique channel number using S2.