Aerotech NDrive HP 10/20/30 Maintenance and Replacement

MXH is closely related to PSO. MXH can multiply analog sine encoder and support real-time orthogonal output. 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. The MXH programming/erasing cycle is about 3.5 minutes, during which the LED will flash and the axis cannot be enabled. After replacing or changing the multiplication parameter, you must wait for the cycle to complete.

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.

Key points of motor and feedback wiring

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. 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. The emergency stop circuit should be kept away from noise sources, and RC networks or varistors should be added to suppress relays or inductive loads.

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, and HP10/20 may experience bus overvoltage due to excessive regenerative energy, requiring the addition of a shunt regulator. 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: ACTV indicates reset, CLMT indicates current limitation, ENB indicates axis enabled, FLT indicates fault, INPOS indicates in place, KRNL indicates controller operation, LMT+/- indicates positive/negative limit, PERR indicates position error exceeding limit, RMS indicates RMS current exceeding limit. Test point TP4 on the control board is for signal sharing. Among the fuses F1-F5 on the power board, F1 and F2 are socket type, while F3-F5 are soldered onto the board. Battery B1 is a 3V button battery, model BR1225.

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. Internal high voltage may still exceed 60 V after a power outage for 10 seconds, and maintenance must be carried out by qualified personnel.

Voltage current mode and independent operation

Firmware 2.06 and above supports voltage current mode. This mode allows NDrive 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 on non A3200 platforms.